os BN ely ely eo eecite ating
é
on ek
“bea tal be heya
et
‘ im
Pray
“Va et For nee
jaa
o
at
ee ae tere ea
WN
ee
»
errr yy
Sa te eb da F whee tifns &-
FOR THE PEOPLE FOR EDVCATION FOR SCIENCE
LIBRARY OF
THE AMERICAN MUSEUM
OF
NATURAL HISTORY
THE GEOLOGIST;
A POPULAR ILLUSTRATED
MONT EUL.Y MAG AA TNE
oF
GHOLOGY.
EDITED BY S. J. MACKIE, F.G.S., F.S.A.
LONDON : “GEOLOGIST” OFFICE, 22, SOUTHAMPTON-STREET, STRAND.
1860.
g4-1325% eae PRINTED AT THE “‘GEOLOGIS2’’ OFFICE, 156, sTRAND
PORE FP AcG
As the snowball gathers weight and size in its rolling, so from the first hour I took charge of The “Guonocisr” has it incessantly gathered strength in rolling on, until now it stands, if my information be correct, unrivalled in circulation by any British scientific periodical.
I may be permitted some gratification in this result; and this feeling of pride is enhanced by the knowledge that of two previous attempts by others, one failed to accomplish a seventh number, and the other died at the third, although aided by lberal donations of plates and absolute gifts of money.
The unvaried success, continued uninterruptedly to the present hour, augurs well and, to me, hopefully for the future. I trust my readers will support me by endeavouring to extend still more the circulation of the magazine, and thus to supply the necessary
“sinews of war’ for its further improvement and enlargement.
My fire burns brightly in the grate; the wind gently whistles at amy window; the moon tips the ripples of the pond in my garden with pearls of silvery light; the air is just keen. By-and-bye the bright coals will burn blue between the flaring flames of the Yule log; old Boreas will lustily howl his hurricane; the pale moon will
anly illuminate the smooth-surfaced ice: and skaters will blow
PREFACRK,
their tingling fingers through their woollen mits. Christmas again is coming ; and a merry, hearty, jovial, happy time may it be to all and every of my friends and readers—aye, and to my enemies, too, if
IT have any ;—on that one day, at least, God bless them.
My thanks are again due to my good and sincere friend, Thos. Davidson, Esq., for his excellent contributions on the Scottish Brachiopoda, and to my other excellent friends, H. C. Salmon, Esq., F. E. Edwards, Esq., Dr. Gibb, T. Rupert Jones, Esq. G. V. Du Noyer, Esq., C. Moore, Esq., Major Austin, and my other contributors.
T ought also to return my best thanks to my very numerous kind querists for the many gratifications they have given me in the pleasures I have had in replying to their interesting questions. Nothing seems to make my editorial labours so light as these kindly communications ; they seem a homely family link between us that
binds us together in the great brotherhood of geologists.
On the Ist of January, 1861, I shall again hoist the old colours, when our ship will appear with fresh decorations, handsome to look at, and in thorough repair. Some new and agreeable passengers will be on board amongst the old sailors, and we shall start vigorously on our fourth voyage.
S. J. MACKTE. December, 1860.
A
Abbeville, Section of Strata at, 407 Acheul, St., Gravelsof, Query on Geologi- cal Character of, by F. Thompson, 73 , Section of Strata at, 405 Alabaster and Lignite in Tuscany, 463 Alton Museum, note on, by W. Curtis, 422 American Fossils, Exchange of, 417 _ Ammonites, Classification of, 396. , from the Gault, 353 ~ Anca, Baron, on Ossiferous Caves in Sicily, 312 Answer to Hugh Miller and Theoretic Geologists, by Thos. A. Davies, re- view of, 277 Archaia, by Dr. Dawson, review of, 158 _ Archeology, General Views on, by A. Morlot, 45
“Arrangement of Minerals, note on, 417 “Arrow-heads, Ancient Canadian, note ~ _ on, by Dr, Gibb, 422
Bicow Heads and M ammalian Remains, in Languedoc, BH. Lartet on, 454
_ Asphalt of Trinidad, 411 Auckland, New Zealand, Geology of,
Dr. Hochstetter on, 184
,
——., Volcanic
Country of, C. Heaphy on, 30
Austin, Fort-Major, on New Genus of
Eechinoderm, 446
Austin, R. Godwin, on Fossils from
Grey Chalk, Guildford, 381
—____——., ona Mass of Coal in Chalk in Kent, 381
Australia, South, Geology of, T. Burr
on, 31
———., Tertiary Deposit in, Rey. J. E. Woods on, 31
Bahia, South America, Fossils from, ‘5S. Ehitport on, 33
INDEX.
Barrett, L., on Cretaceous Rocks in Jamaica, 381
Basalt, Du Noyer on, 5, 9, 13
Beach, Raised at Mewslade Prestwich on, 413
Beads, Fossils at St. Acheul, 406
Belemnites, former opinions of, 355
Bergh’s Theory of Periodic Inunda- tion, 423
Bigsby’s Cavern, Murray Bay, 174
Brachiopoda, New, C. Moore on, 438
Brachiopoda of Scottish Carboniferous System, Davidson on, 14, 99, 179, 219, 258
Bay,
, Lists of Scottish Counties
in which found, 259
, Scottish, Explanation of
Plates of, 265
, Remarks on the Distri-
bution of, by Prof. E. Suess, 285
—, Belgic compared, 235
British Brachiopoda, 459
Bones of Quadrupeds, with marks of Incisions of Instruments, 411
Bosco’s Den, Gower, 414
Boucher de Perthes, Antiquité Ante- diluviennes, notices of, 370
Boulder Clay on Cefn-y-burn, Gower, Prestwich on, 413
Bowen’s Parlour, Gower, 415
British Association Meetings, 26, 298
Bronze Age, M. Morlot on, 49
Bronze Relics in Auriferous Sands in Siberia, T. W. Atkinson on, 30
Bury Cross, near Gosport,a Well-Section at, Pilbrow on, 409
C
Cabinets for Fossils, Letter from E. Wood, F.G.S. on, 351
Camarophoria, Carboniferous, David- son on, 24
————— crumena, 25
Canadian Caverns, Dr. G. D. Gibb on, 131, 161, 213, 341 422,
Canoes, Ancient, Note on, 196
il INDEX.
Carboniferous System of the Lothians, 239
Catalogues of Fossils, note on, 318
Cephalopoda, Classification of, 395
Chaleur, Bay of, Caverns at, 164
Chalk, Grey, near Guildford, Fossils from, R. Godwin-Austen on, 381
-—, Red and White, of Yorkshire, note on Foraminifera in, by Major- Gen. Emmett, 419
Channel, British, Formation of, Mackie on, 255
Cheirotherium, Footsteps of, in Upper Keuper, Warwickshire, Rev. P. B. Brodie on, 34:
Chinese Fossils, Hochstetter on, 419
Chonetes, Carboniferous, Davidson on, 184, 219
—— Hardrensis, 219
——— Buchiana, 221
Clay Slate and Granite, at Halifax, Nova Scotia, note on, 420
Clinometer, Elliott’s, note on, 418
Coal-field, South Wales, Dr. Bevan on, 90
, the Tynedale, J. A. Knipe
on, 315
Coal Formation of Nova Scotia, Ter- restrial Mollnse, Chilognathous My- riapod, and some new Reptiles, Dr. Dawson on, 83
Coal Measures, Upper, Fish and Ento- mostraca in, note on, by G. EH. Roberts, 319
, Fish from, query res- pecting works on, 392
Coal, Mass of, in Chalk, in Kent, R. Godwin-Austin on, 381
Coal Mines at Nagasaki, note on, 421
Collections, Tennant’s Mineralogical and Geological, 40
Common Fossils, 8. J. Mackie on, 1
Comparative View of Human and Animal Frame, by B. Waterhouse Hawkins, 200
Corals, Upper Silurian, Roberts on, 55
Cornwall, Geology of, notes on, 199, 350
Corrugation of Strata in the Vicinity of Mountain Ranges, Rev. J. Dingle on, 314 *
Crag Shells, Aberdeenshire, 454
Craniade, Carboniferous, 222
Crania, Davidson on, 222
quadrata, 223
Creation Redemptive, by Rey. 8. Lucas, review of, 155
Cretaceous Period, the Probable Events which Succeeded the Close of, 8. V. Wood, jun., on, 382
Cryolite in Manufactures, 466 Cyrena Dulwichiensis, C. Rickman on, 211 D
Damon, R., Geology of Weymouth, Review, 432
Davidson, T., On Scottish Carboni- ferous Brachiopoda, 14, 99, 179, 219, 235, 258
Dawson, Dr., on Fossil Fern from Nova Scotia, 456
Delesse’s Researches on Pseudomorphs, 396
Denudation of Soft Strata, Rey. O. Fisher on, 455
Denudation of the Wealden Area, Mackie’s Theory of, 203
Devonian Fossils of Cornwall, Geolo- gical and Chronological Distribution of, by W. Pengelly, 309
Discina, Davidson on, 225
nitida, 226
Discinide, Carboniferous, Davidson on, 225
Drift, C. B. Rose on, 137, 317
, I. F. Jamieson on, 383
Dulwich, Tertiary Strata at, C. Rick- man on, 456
Du Noyer, on Limestone in Old Red Sandstone, 272
, on Giant’s Causeway, 3, 142 , on Slickensides, 39
E
Edwards, F. E., mani, 209 Envelopment of Minerals, Table of, 398 Evidences of Geelogical Age of Human Manufacture of Fossil Flint Imple- ments, Mackie on the, 404 Exchanges of Fossils, 459
on Pitharella Rick-
i
Falconer, Dr., on the Ossiferous Caves of Gower, 413
— ,Fauna of the Bone Canaa 416
Fern, Fossil, from Nova Scotia, Dr. Dawson on, 456
Fire by Friction, note on, 120
First Traces of Life, by 8. J. Mackie, review of, 160
Flints, Professor J. Tennant on, 35
Flint Implements, 35 ; in the Museum at Beauvais, 79; at Hoxne, 348
» Fossil, in America, 351
Flint Implements, Evidence of Geolo- gical Age and Human Manufacture of, Mackie on, 4.04
, Notices of at Grenoble, by E. Lartet, 412
Flora of the Silurian, Devonian, and Lower Carboniferous Formations, Prof. Goeppert on, 115
Flower, J. W., Flint Instruments found by, at St. Acheul, 405.
_ Folkestone, Geology of, Mackie on, 41,
81, 121, 201, 281, 321, 353, 393
~ Foraminifera in Red and White Chalk
of Yorkshire, Major-Gen. Emmett on, 419
,In Upper Lias Clays, near Derby, Jones and Parker on, 409
Formations below the Stonesfield Slate in Oxfordshire, Hull on, 303
Fresh-water Deposits of Bessarabia, 115
Frome, Small Vertebree from, Prof.
P Owen on, 454
_ Fruit, Fossil, from Upper Coal Mea-
sures, note on, by J. Taylor, 198
q
G
Gainford,ncarDurham, Fossilsfrom, 120 ~ Gems of Private Collections, 448 Gems in Situ, 118 Geological Examinator, the, by David Page, review of, 279 Gossip, by Prof. Ansted, review of, 320 Habitats of Some Rare British Plants, Rey. W. 8. 8ymonds on 313 —— Localities, 41, 81,121, 201, 281, 321, 353, 393 Society of Manchester, 135 ——— of Liverpool, 70,
in?
116, 134 _-——______—. of London, 30, 69, 115, 133, 379, 408, 454 Topics, 371 Works, New, note on, 199 Geologists’ Association, 34, 270, 416 _ Geology in the Garden, by Rev. H. Eley, review of, 79 Giant's Causeway. 3 Gibb, Dr. G. D., on Canadian Caverns, s 131, 161, 213, 341 SeAaciors, the Old, of Switzerland and North Wales, by Prof. A. C, Ramsay, review of, 278 alasgow Geological Society, 457 d Depusits, Dr. Genth’s views on, 63 Gold Drifts of Ballaarat, note on, by W. J, Morgan, 153
Du Noyer on,
INDEX. ii
Gower, Ossiferous Caves of, Dr. Falco- ner on, 413 Great Oolite of Stonesfield, Thickness of Formations Below, H. Hnll on, 303 H
Hammers of Stone and Flint, 385
Harkness, Prof. R., on Metamorphic Rocks of North of Ireland, 311
, on Old Red Sandstone and
Metamorphic Rocks on Southern Margin of the Grampians, 379
Heat, Theory of Gradual Withdrawal of, by J. Curry, 273
Heterostegina Bed at Malta, 137
Hibberti on Fossil Fish, 350
Hodge, H. C., on the Oreston Caverns, 343, 377
Hoxne, Flint Implements at, 347
Hull, E., on Blenheim Iron Ore and. Thickness of the Strata below the Stonesfield Slate, 303
Human Remains, Fossil, Accounts of, 39
Published
at Knaresborough, REZ
Skeleton in Old Sea Margin, T. Austin on, 70
I
Ice-Action, Hvidences of Ancient, at Liverpool, G. H. Morton on, 197
Tnundations, Periodic, an Essay on, by A. Bergh, review of, 423
Tron Ore at Blenheim, E. Hull on, 303
, Remarkable Property of, 351
Isomorphism of Stannic, Silica, and Zirconic Acids, 62
J
Jamaica, Cretaceous Rocks in, 381
Jervis, W. P., on the Geology of Tus. cany, 413
Jewstone, G. E. Roberts on, 319
Jones, T. Rupert, on Outliers of Ter- tiary Ironstone on the North Downs of Kent, 339
——____—__—-_ and W. K. Parker on Rhizopodal Fauna of the Mediter- ranean, 69
, on Triassic Foramini-
fera, 409
K
KeuperFormation, G. H, Morton on, 116
iv INDEX.
Kirkby, J. W., on Sandpipes in Mag- nesian Limestone, 293, 329
L
Lamellar Structure of Rocks, 391 Lapis Lazuli, note on, by G. EH. Ro- berts, 319 Lepidotus and Lepidosteus, Scales of, Lee on, 458 Leptzena Davidsonii, 445 Lias, Lower, of South of England, Dr. Wright on, 310, 133 at Whitchurch, note on, 392 Lingulide, Carboniferous, 227 Lingula, Davidson on, 227 ————., Anatomy of, 228 squamiformis, 232 scotica, 232 mytiloides, 234 Lingula-flags, Mackie on, 1 Lingula Credneri, in Coal-Measures of Durham, J. W. Kirby on, 384 London Clay, in Norfolk, 409 Ludlow, New Fossils from, 462
M
Mackie, S. J., on Common Fossils of Lower Silurian Rocks, 1 , on First Traces of Man,
370
— , on the Geology of Folke- stone (the Gault), 41, 81, 121, 201, 281, 321, 353, 393
——,, Geology of the Sea, 241
Malta, Geology of, notes on, 198, 421
, Fossiliferous Localities in, 276
Malvern Field Club, 35
Mammalian Remains at Bridlington, 119
at Folkestone, 282 at Frogmore, 421 at Petteridge,421
—____—___—__—— at Salisbury, 77
Man, Biblical Chronology of, 136
, Co-Existance of with certain ex-
tinct Quadrupeds, HE. Lartet on, 411
, First Traces of, Mackie on, 307
Maps, Geological, Reynold’s, reviewed,
472 Metalliferous Deposits, Current Notes on, by H. C. Salmon, 62 Saddles in Lower Carboni- ferous Rocks in Derbyshire and Staffordshire, Dr. Watson on, 357 Metamorphic Rocks of North of Ire- land, Prof. Harkness on, 311 Metamorphism of Rocks, Delesse on, 65
Meteorite of Agram, 459 Mineralogical Notes, by H. C. Salmon, 62 Minerals, Arrangement of, note on, 417 , Envelopment of, 397 , Tables of, 398 Mitchell, Rev. H., on New Fossils from Lower Old Red Sandstone, 275 Mongrel Words, note on, 377 Monoliths, at Boroughbridge, 390 Moore, C., on the Contents of Three Cubic Yards of Triassic Earth, 315 , on Wealden Beds, at Linksfield,
409
Morlot, M., on some general views on, Archeology, 48
Mountain Limestone Works, on Fossils, 463
Museum, Alton, note on, by W. Curtis, 422
Museums, Provincial, Suggestions Respecting, by E. Charlesworth, 117
——___—_—____,, by G. Horner, 136
N
New Red Sandstone of Wolverhamp- ton, Rev. Wm. Lister on, 308
Nagasaki Coal Mines, 421
Nicker Pits at Canterbury, 277
Norfolk, London Clay in, Prestwich on, 409
Norwegian Lakes, Probable Glacial Origin of, T. Codrington on, 383
Notes and Queries, 36, 70, 117, 135, 184, 271, 317, 347, 385, 416, 458
O
Old Red Sandstone of Forfarshire, Fos- sil Fish of, W. Powrie on, 336
, Fossiliferous Lo- calities of, in East of Scotland, note on, by J. R. Gregory, 142
—______—__, Fossil Fishesin, 147
, Limestone Veins
in, 135, 273
—_——- , New Fossils from,
Rey. Hugh Mitchell on, 273 ——_—_——— and Metamorphic of
Rocks the Grampians, Prof. Hark- ness on, 379
Oolites, Lower, of Oxfordshire, Inver- tebrata of, J. Whiteaves on, 307
Operculum of an Ammonite in Situ, S. P. Woodward on an, 328
Oreston, Ossiferous Caverns at, H. C. Hodge on, 26, 343, 377
Origin of Species by means of Natural Selection, by C. Darwin, Review of, 464,
Orthis, Carboniferous, Davidson on, 99
resupinata, 99
Michelini, 101
Ossiferous Caves in Sicily, 312
Owen, Prof., on Polyptichodon, 32
Oxford, New Geological Map of, 302
, Strata at, Phillips on,379
iP
Page’s Handbook of Geological Terms, Incorrectness in, 36, 135 Palzchinus, Austin on, 447 Palzeontographical Society’s Works, 277 Paradoxides Bennettii, 2 Peckham Rye, New Fossils at, 77 “Peckham and Dulwich, Fossil Remains in Tertiary Strata, 151 Pengelly, W., on Distribution of Deyo- nian Fossils, 309 Phillips, Professor, on Some Sections of Strata, near Oxford, 379 Pictured Rocks, Lake Superior, 169 Pilbrow, J., on a Well-Section at Bury Cross, Gosport, 409 Pillar Sandstones, North Coast of Gaspe, 166 Pitharella Rickmani, Edwards on, 209 Phosphate of Lime, 87 Plant, from Coal-Measures of South Wales, Dr. Bevan on, 460 Plants, Coal, Preservation of, 199 Pleistocene Deposits at Liverpool, 277, 349 Polyptichodon, Prof. Owen on, 32 Poole Harbour, Letter on, by P. Bran- non, review of, 430 Powrie, W., on Pteraspis from Old Red Sandstone of Forfarshire, 336 Pre-adamite Man, review of, 155 Prestwich, J., on a Raised Beach in Mewslade Bay, 413 , London Clay in Norfolk, 409 Proceedings of Geological Societies, 30, 69, 115, 133, 271, 379, 454, 408, 454 Productidz, Carboniferous, Davidson on, 105 -Productus, Carboniferous, 105, 179 ——— fimbriatus, 114 costatus, 179 Youngianus, 180 aculeatus, 181 spinulosus, 182 mesolobus, 182 pustulosus, 182 giganteus, 106
INDEX.
Productus latissimus, 107 — semireticulatus, 108 longispinus, 110 carbonarius, 111 cora, 112 ———— undatus, 112 scabriculus, 113 punctatus, 113 , De Koninck’s groups of, 183 Protoechinus, Austin on, 446 Pseudomorphs, Delesse’s on, 396 Pteraspis and Coccosteus, 460 Pteraspis, in Lower Ludlow Bed, Dis- covery of, 79, 151 Punjab, Geological Notes on the, by J. Calvert, F.G.S., 348
Q Quaternary Geology, by S. R. P., 136
R
Reading, Geology of, note on, 350, 390
Red Chalk of Yorkshire, 110
Gen. Emmett on, 419
Re-Oceurrence of Fossil Species at Various Stratal Horizons, 149
Reptiliferous Strata, near Elgin, Rev. W.S. Symonds on, 410
Reviews, 40, 79, 117, 155, 200, 377, 320, 377, 423, ‘464,
Rhinoceros, Extinct Species of, Dr. Falconer’s Researches on, 148
Rhizopodal Fauna of the Mediter- ranean, Jones and Parker on, 69
Rhynchonellidee, Carboniferous, Dayid- son on, 22
Rhynchonella, Davidson on, 22
pugnus, 23
—————_—— plurodon, 24
Roberts, G. E., on Severn Valley Rail- way, 433
, on Upper Silurian Corals, 55 Rose, C. B., on the Divisons of the Drift in Norfolk and Suffolk, 137, 317 , on the Strata Containing Flint Implements at Hoxne, 347
)
Sahara, Geological System of, 305
Salmon, H. C., Mineralogical Notes, 62
——————,, on Pseudomorphs, 396, 450
Salter, J. W., ou Ludlow Pteraspis, 79
, Silurian Rocks of Ireland, 151
Sandpipes in Magnesian Limestone of
Durham, J. W. Kirkby on, 298, 329
V1 INDDX.
Scotland, Highlands of, Rocks, Ores, &e., on the Property of the Marquis of Breadalbane 385
Sea, the Geology of the, Mackie on, 241
Severn Valley Railway, Roberts on, 433
Sicily, Ossiferous Caves in, 312, 410
Silurian Rocks, Abergele, 76
—_— , Lower, Mackie on, 1
of South-east of Treland, T. Austin on, 70
of Ireland, Letter 151
Silver in California, note on, 351
Slickensides, 37, 38, 76, 117
Sligo, Geology of, 317, 350
Skipton, Map of, review of, 200
Smoking Pipes in Alluvium 78,119
Spirifera, Carboniferous, Davidson, 15
duplicicosta, 16
——_—— hisulcata, 16
trigonalis, 17 pinguis, 17
——— oyalis, 18
glabra, 18
Carlukiensis, 19
——— Urii, 19
—— lineata, 20
Spiriferina, Carboniferous, on, 20, cristata, 21 insculpta, 22
—laminosa, Davidson on, 234
Spitzbergen, Goology of, J. Lamont on, 408
Spongeous Nature of Flints, Chemical Evidence of, 271
Steinhauer Cavern, the, 171
Stone-Age, M. Morlot on, 49
Stone Axes, Manufacture of, 349
Implements, Manufacture of, 392
Stonesfield Slate, W. 8. Horton on, 249
Streptorrhynchus, Carboniferous, Da- vidson on, 103
Davidson
é crenistria 103
Strophomena, Davidson on, 102
— rhomboidalis, 102
Strophomenida, Carboniferous, 99
Succession of Life, First Traces, 1
Suess, Prof. E., on Distribution of Bra- chiopeda, 285
Symonds, Rey. W. S., on Geological Habitats of Some Rare Plants, 313
, on Reptiliferous Sandstone,
near Elgin, 410
T
Tate, C., on Carboniferous Strata, 238 Terebratella, Development of Loop in, Moore on, 441
Terebratella Buckmanii, 441 furcata, 442 Terebratula maxillata, 440 ———— hemispheerica, 440 Terebratulina radiata, 443 Tertiary Ironsand of North Downs of Kent, 339 Plants of Austria, 460 Toads, Living when Shut in Plaster for Years, note on, by M. Seguin, 421 Travertine, at Kinder Scout, 416 Triassic Earth, the Contents of Three Cubic Yards, Moore on, 315 Trinidad, Geology of, G. P. Wall on, 410 Tuscany, Geology of, 413
U
Unio and Paludinz of Wealden Mar- ble, 448
Vv
Vegetable Fossils in Flint, 197 Verstegan’s Observation on the former Connectionof Franceand England, 204
W
Warp, Deposition of, E. Tindall on, 39
Waste of Land in Yorkshire, 421
Watson, Dr., on Metalliferous Saddles, 357
Wealden Area, Denndation of the, Mackie on, 203
— Beds at Linksfield, C. Moore on, 409
Wexford Schists, T. Austin on, 391
Weymouth, Geology of, by R. Damon, review of, 432
Woodward, 8. P., on an Operculum of an Ammonite in Situ, 328
Worcestershire, the Rocks of, by G. E. Roberts, review of, 279
Worms, Influence of, in Formation of Soils, Rev. H. Eley on, 80
Wright, Dr. T., on Avicula Contorta Bed and Lower Lias of the South of England, 310
Z
Zellania, C. Moore on, 444 —— globata, 444 —— oolitica, 444
~~ S Q &
Chalk Cliffs capped by Basalt 4 Junction of Basalt and Chalk 5 Irregularly Deposited Basalt 6 View of Giant’s Causeway. a The “Organ”. . “ual Ge ahs! . Cliffs South of Portnoffer Ag Ay The Whin Dyke. . . + 10 . Coast of Giant’s Causeway oy nl . Grouping of Basaltic Columns 13 . Interior of Athyris ambigua 15 . Interior of Spirifera striata . 15 . Rhynchonella psittacea . . 23 . Interiors of Camarophoria. . 25 . Fragment of Slickensides. . 39 . Eastwear Bay, Folkestone . 41 . The “ Warren,” at Folkestone 43 . Section at Waterford Haven. 72
Lo OOIAMS wry Z
[8. Ammonites Lautus .. . 81 . Ammonites varicosus . . . 82 . Ammonitestuberculatus . . 82 . Ammonites auritus. .. . 83 . Rostellaria Parkinsonii . . 83 . Hamites rotundus a Oe
. Ammonites interruptus. . . 85
. Fragment of Dicotyledonous Wood bored by Toredo . . 86 . Copt Point, Folkestone . . 87 . Ammonites mammilaris . . 88 . Interior of Productusgiganteus 106 . Belemnites Listeri ER. . Solarium ornatum . 124
West Cliff, Folkestone, with capping of Mammaliferous
DEG. ses . 125
. Sandgate, Kent . . . 126 Kentish Rag and Wealden
Beds ... Le or ehae
. “ Jill’s Pipe,” Lympne . . 128
. Shrinkage Joints in Trap. . 142
. Nodule from Tynet . . . 145 Disjointed Nodule in Old Red
Sandstone . 146
. Fruit from Bolton . . 198
. Small Fruit fromBolton . . 198 Map of the Denudation of the
Pen 5 +s 208
41. Crania Ignabergensis 222
42. Animal of Discina 225
Lingula anatina . . |. 228 Carboniferous aes of the Lothians .
INDEX.
Vil
PAGE,
. Vertical Veins of Limestone
in Red Shale, at Templemore 272
. Explanatory View of Sea-bed
forming the Strata at Tem-
plemore . . 278 . Bone of Bos primigenius 2 tetZBE . Chalk Downs, near Folkestone 282
“ Bull-dog” Steps, Folkestone 283 . Section, showing Sandpipes . 294 . Pipes in Magnesian Limestone 296 . Tubular Sandpipes c 297 . Ammonites Bouchardianus 321 . Inoceramus sulcatus 322 . Inoceramus concentricus . 322 . Nucula pectinata . 322 . Nucula ovata . 322 . Nucula bivirgata. 323 - Nucula ornatissima . 323 . Plicatula pectenoides 323 . Ostrea Rauliniana 323
62. Lima parallela Gault . . . 324 » Arca carimata. . . . » «824 64, Turritella vibrayeana . 324 65. Scalaria Clementina. 325 66. Cast of Scalaria Dupiniana . 325 67. Acteon vibrayeana 326 68. Ringinella Clementina . 326 69. Natica gaultna . . . . . 326 70. Solarium dentatum . 327 71. Solarium conoideum. 372 72. Dentalium decussatum. 327 73. Bellerophina vibrayeana . 827 74, Ammonites subradiatus, with the Opereulum in Situ 328 75. Oblique Sandpipes . . . 329 76. Decomposed Limestone sur- rounding a Sandpipe . 330 77. Pipe in Rubble . 2 . 331 78. Hinder Portion of Pterygotus 337
, Contorted Beds of alternating
. Sandstone Hammer ., . Sandstone Hammer.
. Ideal Section explanatory of
the Driftand “Kentish Crae”’ 340 . Plicated Strata, North Stafford- shire . 358
Limestone and Shale. . 360
. Ideal Section of Limestone
Strata in North Staffordshire 363
- Mode of Deposition of Ore,
North Staffordshire . . . 365 . 386
. 386
yi INDEX.
FIG. PAGE. 86. Stone Hammer... . . 887 87. Vesuvian Leucite . . . 400
88. Parallel Zones of Ripidolite . 401
89. Ferro-magnesian Mica enve- loping Aluminous Mica. . 402
90, Ordinary Pear-shaped Flint Implement, from the Gravel
of St. Acheul . . . 405 91. Flint Implement found by Mr. J. W. Flower . -. . 505
92. Fossil Bead, formed of the little Chalk-sponge, Cosci- nopora globularis . . . . 406
FIG. PAGE. 93. Flint Implement fixed to a Stout Pole, in illustration of its probable use as a Spear- or Javelin-head. . . . 406 94, Travertine deposited by stream near Kinder Scout, Derby-
shire . . 417 95. New Plant. from Coal Mea, sures, South Wales. . . 461
96. Section of Rocks, Pedwardine 462
97. New Fossil Bryozoan (?), from Wenlock satis near Adfor- Worle 5c +) *ee WZ
Lil S Poe
P nA Pass
PLATE To Face Page I. Scottish Carboniferous Brachiopoda . ..... =: ». « « «| 2 II. Scottish Carboniferous Brachiopoda ...... .. =. . ~ 104 III. Scottish Carboniferous Brachiopoda ...... +... =~. . 180 IV. Scottish Carboniferous Brachiopoda PI, che an et VY. Pitharella Rickmani and Cyrena Theat . . (Frontispiece) 212 V*. Bryon Island and “The Old Woman” of Gaspe .* ... . . 164 VI. View of the Pierced Island, in the Gulf of St. Lawrence. . . . . 182 VI*. Caverns and Arched Rocks at Percé, Gaspe. . ... =... « 162 VII. Basaltic Caverns at Henley Island . ae ella VIII. Basaltic Dykes of Mecattina . rrenc ys cL IX. Bigsby’s Cavern . Poe te we ie alg) Me ete es le tt an X. Bouchette’s Cavern, Kildare, Camada . . =. . 9. © « os ueennlao XI. Murray’s Cavern and Subterranean River, Ottawa . ... . 218 XII. Sections of Bones of Recent Lepidosteus of the aia and of Lepidotus Fittoni from the Wealden of Sussex . . . ~ Voe aos: XIII. Development of Loop in Terebratula . . . . PMerees) oh: Salah XIV. Slab of Bethersden Marble, with Unio and Paludina . 2 0 2 eR Sas
es fs
f
i | | }
THE GEOLOGIST.
JANUARY, 1860.
THE COMMON FOSSILS OF THE BRITISH ROCKS. By S. J. Mackin, F.G.S., F.S.A.
(Continued from vol. ii., page 427.)
Cuar. 7.—First Traces of the Succession of Life-—The Lower Silurian Rocks.
OsscurE as are the animal remains of these old Lingula-flags, the traces of vegetation are yet more difficult to make out and to describe. Lasier, too, are they to describe than to figure; for, mere shallow impressions and stains as they are upon the cleaved rock, it is easier to see their remote resemblances to some known forms than to convey an idea of them by the finest lines that the graver will cut upon the wood. And then how unsatisfactory to spend days in elaborating the representation of a mere fragment, the very charac- ters of which we are in doubt about.
We shall shortly present our readers, however, with figures of the most illustrative specimens we can obtain of those sea-weeds of the primeval shores, the Cruziana semiplicata, the Chondrites (?) acutangulus, and Chondrites (?) informis.
In North Wales, near Tremadoc, an upper portion of the Lingula- flags, consisting of dark grey or blackish schists with thin layers of
grit, has been made out by Mr. Salter. This upper zone, in addition
to the Lingula awisii and Agnostus pisiformis, presents us with two
other forms of trilobites, Conocephalus invitus (Salter), and Elipso-
cephalus (?) depressus (Salter), with a bryozoan (plate ii.), the oldest
of the group yet known, supposed to be allied to Fenestella, and VOL, Il. A
2 THE GEOLOGIST.
intermediate between the Fenestellida and the Graptolites, and named Dictyonema (Graptopora) socialis by Mr. Salter; also a small Orthis and a Scandinavian trilobite, Olenus alatus of Beck. The fossil Dictyoneme completely cover the surface of a black slaty layer at that place; and near Maentwrog and Ffestiniog the same bed has been observed overlying the lighter coloured and more sandy mass of the Lingula-flags proper, and apparently forming a conformable bed of passage into the lowermost portion of the Llandeilo group.
Such then, and so scanty, are all the trophies as yet obtained from these ancient silurian rocks—the Lingula-flags. Let us cast our eyes over the equivalent rocks in other lands. In North America vast is the development of the Potsdam sandstones which represents them, but in these the fossils are like, and few. In Bohemia, Scandinavia, France, Georgia, and other places it is the same.
From Newfoundland, during the past year, we have indeed been presented with a giant trilobite nine inches and a-half across, and named by Mr. Salter Paradowides Bennettii. But this difference only of size from the other species of the same genus in these rocks, con- firms rather than depreciates the conclusion which Sir Roderick Murchison has come to of the paucity of life-forms at this early stage of the elaboration of the stratified crust of our planet.
Whether the geographical distribution of particular species in particular regions at that remote era will be established as a fact or not, it is certain that the range of organic forms was at its maximum then; while the similarity of the forms presented in regions far remote and apart, seems certainly to indicate more equitable condi- tions of climatal relations. This is what we should expect from the general low oosy character of those tide-washed lands, and the still warm and reeking atmosphere in which the whole globe was pro- bably enveloped.
Let us pause for one moment on the strange scene. That great expanse of sea, those wide, flat, muddy shores, over which the un- checked tides ran rippling with rapid speed in a thin sheet, waving into life the silken weeds, and ebbed as quickly, triturating in their unctuous passage the fine material particles finer and finer, leaving tiny pools innumerable, shallow lagoons, and mimic lakes for Hymenocarides and Trilobites to sport and grovel in. How glori-
DU NOYER—NOTES ON THE GIANT’S CAUSEWAY. 3
ously the pale “ queen of night” must have shed her rays along that glistening tract, and how fair and white the long curling shore-waves must have looked, as they caught with their rolling crests her silvery beams, and perchance reddened in the glare of some raging volcano. Over the endless ocean the glittering flood of light ranged away, until far, far off in the grey and misty horizon, it mounted to the clouds, and seemed to mingle earth with heaven. How beautiful must have been the moon’s light then, when only the trilobites turned their hundred-lensed eyes towards her, and skipping Hymenocarides in their sportive progress, spattered out of the shadowy pools sparks and flashes of bright light. What a world of silence, unbroken save ~ by the rushing of the wind, or the murmurs of the sea. No beast upon that oosy land, where nor grass nor herbage grew. No birds nor insects in that dewy air; nor waves nor ripples landed the glit- tering fish upon those slimy shores ; the wide expanse of waters was untenanted by the scaly tribe, and the sluggish shell-fish, worms, and three-lobed crabs, and their shrimp-like congeners, were the sole tenants of the earth.
(To be continued.)
NOTES ON THE STRATIGRAPHICAL POSITION OF THE GIANT’S CAUSEWAY, AND THE STRUCTURE OF THE BASALTIC CLIFFS IMMEDIATELY ADJOINING IT.
By Geo. V. Du Noysr, M.R.1.A., Senior Gronocist oF THE GEOLO- GICAL SuRVEY OF IRELAND.
Duriné a visit to the Giant’s Causeway in the month of September, 1857, I made a few notes and sketches on the spot, having reference more particularly to the determinating of the stratigraphical position of the Causeway itself, and to get if possible a clear idea of the struc- ture of the exposed cliff-sections of the basalts in the immediate neighbourhood. On comparing my observations with an account of the causeway and the adjoining coast given by the Rev. John Dubourdien in his statistical survey of the county of Antrim in 1812, I was struck with the discrepancies which exist between them, the
4 THE GEOLOGIST.
author’s idea being that the bed of Basalt forming the Causeway ex- tended eastward to Portmoon, a distance of two-miles (page 46), and that the whole of the strata are parallel to each other. These sup- positions are, as far as I am aware of, adopted by all subsequent writers on the Causeway ; and as they are errors, a transcript of my notes may not be unacceptable to the readers of the “ Gronocisr ;” they tend at least to illustrate more fully the structure of the Basaltic deposits to which I allude, and are a few additional facts added to our present information on this interesting subject.
Proceeding to the Causeway from Portrush, when we arrrive at Dunluce Castle the views of the coast are remarkably striking and instructive. That to the west, from a window in Dunluce Castle (Fig. 1) shows the junction of the Basalt and Chalk
Lign. 1.—View looking west, from a window in Dunluce Castle. Chalk Cliffs capped by Basalt.
most admirably. The Basalt, which for the height of some hundreds of feet above the Chalk is quite amorphous, is seen capping all the low chalk promontaries along the coast. Between Portrush strand and the stream adjoining Dunluce Castle on the west, the absolute junction of the two rocks can be closely studied in many places on the road which passes over the cliffs alluded to, the surface of the chalk on which the basalt rests beg very uneven, and in some places excavated into wide and deep gullies like the transverse sections of river-courses; at others it presents bluffs or possibly headlands against which the basalt has flowed, and which it eventually com- pletely overlays. In this view the cliff close to the spectator is
DU NOYER—NOTES ON THE GIAN1’S CAUSEWAY. 5
formed of bedded basalt which rises from the sea, the adjoining head- land beyond it being chalk; thus we have an example of the latter kind of junction between these two rocks, as the supposition of their being brought together by a fault is not tenable.
To make this paper more complete I have introduced the accom- panying sketch of the junction of the basalt and chalk on the Port- rush shore, as showing that fact more in detail.
NAY !>
Nee
, 00 Co®
% © L)
Lign. 2.—Junction of Basalt and Chalk, Shore of Portrush, Co. Derry.
a. Amorphous basalt, becoming so decomposed in its lower portion as to resemble dark brown earthy shale.
b. A layer of drift-flints, water-worn, enclosed in what is now hardened, or baked chalk-mud—the flints being most numerous at the bottom of the deposit. This rests on the erroded surface of the chalk proper (¢), showing that before the deposition of the basalt, that rock had been subjected to forces of sub-marine denudation, and that the basalt flowed over it while so submerged. The chalk, though not distinctly bedded, exhibits numerous lines of lamination, which are parallel to the direction of the layers of flint (d). Numerous joinis rather wide apart traverse the chalk layers at their upper part, vertically.
The view (fig. 3) also from Dunluce Castle is in the opposite direction to the former, or looking east towards the Causeway-
6 THE GEOLOGIST.
headlands ; the low promontary in the foreground is formed entirely of bedded basalt apparently of different degrees of hardness, and is exceedingly interesting, as affording an insight into the true manner in which basaltic flows of unequal compactness are de- posited, a single bed of harder basalt being observed to branch
a
— = == ——— TR > Ni i ae = ge te j ili Hill Nae
-- SE
hm itn, wr i Ny hee
om
= 2 SSS AST 5
=
Lign. 3.—View looking east from a window in Dunluce Castle, the Causeway-headlands in the distance. Irregularly deposited Basalt.
off so as to form two beds, each equal in thickness to the first; while in another part of the cliff two beds join into one bed, which then equals their united bulk. These are facts that we must bear in mind when examining and describing the Causeway and the adjoining cliffs.
To the spectator who stands on that bed of columnar basalt called “The Giant’s Causeway” the view presented on the north-east, across _ Portnoffer Bay, embraces the profile of the Chimney-headland, half a mile distant and three hundred and eighty feet in elevation, as well as that of the nearer and less lofty projection of the coast east of Portnoffer, three hundred and twenty-seven feet above the sea. Adjoining this is the group of columns called “The Organ,” part of which is shown at the extreme right of the view (fig. 4); th distance between the “ Chimney”’-head and Portnoffer-point is only two hundred and fifty yards.
GIANT’S CAUSEWAY.
DU NOYER—NOTES ON THE
“SUTINION-UBSIO OY} JO Jw *X “Spoq omTpIO SAA A
‘OTTO B [BY JuVISIp pus “WN suLreoq puvyproy-AouunyO oy}
‘KBMOSNBD SJUBLD OY} WOT, MOLA—'f ‘UST
Lip ete EEE a= LYLE NEED YFP F?”
8 THE GEOLOGIST.
The section at the Chimney-headland is as follows: commencing at the top, two thick beds of columnar basalt, closely resembling ‘ each other in appearance, a few columns of the top one being left standing apart fioni the main mass at the edge of the cliff, thus sug- gesting the idea of the “chimney ;” the floor of the upper bed is re- markably level. These columnar basalts rest on what is known as the great ochre bed—a well marked feature in the section. Below this ochre layer the remainder of the cliff consists of possibly four deposits of amorphous basalt, each separated from the other by a thin layer of ochre.
In the lesser headland, east of Portnoffer Bay, the section is very similar to that just described; the two upper columnar beds are again recognized, and together rest on the ochre bed, which here, however, has become considerably thinner, and, owing to a steady dip of about five degrees to the west in all the beds at that side of the Chimney-head, it is now much nearer to the sea than before; this may be the result of a slight upheaval en masse of the beds at the Chimney-headland.
a a ae Samii —— <r f Pris ou or i cm My oy \ Nive
yi ny i a Niet Fs
Fy li Wg
a, a i it
Nigaifl caut
Lign. 5.—The “‘ Organ.”
Tf we attempt to follow the great ochre bed towards the Cause- way, or in its western extension, it appears to thin out, and to be easily concealed by the debris from the cliffs above, and eventually a very marked change is observed in the superimposed
DU NOYER—NOTHES ON THE GTANT’S CAUSEWAY. 9
columnar beds; they also become thinner, and lose their remarkable parallelism of deposition, as well as distinct columnar structure ; The upper one is now but rudely columnar, and the columns are much thicker than those of the bed below; the underlying ochre- layer is wanting, and its place is supplied by a deposit of amorphous basalt, which now attains a thickness equal to that of the super- imposed columnar beds. This change of structure in the cliff-section occurs in a distance of less than three hundred yards. Below this amorphous basalt a new columnar bed of trap appears, the pillars of which are exceedingly symmetrical in every respect, and of great beauty ; they are exposed for the distance of about two hun- dred feet, and are all inclined to the eastwards ; while their upper surface, which is very even, slopes to the westward at about six to eight degrees. This group of columns is called “The Organ’’ (see figs. 4 and 5).
Below this bed, though not absolutely seen, the missing ochre- layer is presumed to be. If we now follow the cliff section west- ward, we find that the “organ-bed” in its extension to that direction, and with its dip of six to eight degrees would eventually be brought so low that more than one-half of its thickness would be emersed below the level of the sea, leaving the remainder to project above the water, and thus to form that singular looking natural pier called “The Giant’s Causeway.” At this spot the thickest and very nearly the most central portion of this particular lava-flow is reached, and it is worthy of remark that here the columns on the east side of the Causeway, which is about one hundred and sixty feet across, in- cline to the east, while on the west side they slope to the west, thus showing in their vertical arrangement a radiation from a series of centres, all following a given line, which would have very nearly a meridional direction, or in other words that of the longest axis of the lava-flow. This structure, I have no doubt, would be apparent throughout the entire of this particular bed if we had the power to examine it throughout, indeed the view which the cliffs afford of it is almost conclusive on this point, as it exposes a transverse section of it in two of its most important positions, viz., at the “ Organ-” columns, near its eastern termination, and at the Causeway, close to its centre.
VOL. II. B
10 THE GEOLOGIST,
Tn the cliffs to the south of Portnoffer, adjoining the Causeway, which average from two hundred and seventy feet to three hundred and seven feet in elevation (fig. 6), the two columnar beds, which
280 feet
: aga STOLE TALEO Ue) fer fll
ae 97
py.
Lign. 7,—The Whin Dyke.
are so distinct at the summit of the “ Chimney-” headland, are repre- sented by not less than possibly four separate deposits of trap; the
DU NOYER—NOTES ON THE GIANT’S CAUSEWAY.
two lowest, which occupy the central position of the cliff, are rudely and mas- sively columnar, and are separated from each other by an irregular layer of rotten black shale, which at one period was searched for coal, and is still known as the “coal-mine ;” the lower portion of this shale is a dull brownish-red earth. Above these columnar beds the re- mainder of the cliff is composed partly of amorphous trap and a group of small columns, which are bent out of the per- pendicular, being overlaid by a thin layer of horizontal columns, which ter- minate the chief section.
At this locality the cliff is traversed from its base to its summit by a whin dyke, fifteen feet thick, the strike of which is about north-west and south- east (Lign. 7).
The projection in the coast directly south of the Causeway and overhanging it, called ‘“ Ard snoot,” is three hundred and seven feet above the sea. It ex- hibits two well-marked columnar beds, most probably the representatives of those at the Chimney-headland. They appear to be of equal thickness, but the upper bed, which forms the summit of the cliff, exhibits small, well-formed, but partially bent, or irregularly bulged columns; while those of the lower bed are unusually large, rudely formed, and more vertical.
From the observations which I have been able to make, it would appear that the bending of basaltic columns in situ may be accounted for in two ways:
Weirs Snoot,
43
fo}
(o}
ad
n— 5!
Lo} m
4
% f
FE SH Fat
ey
4A
lo}
4
a
qe
A
#
Oo
ay
Chimney Head,
N.E,
Organ-columns.
Great Steucan Point. Amorphous Basalt below the Ochre bed.
Causeway, with Whyn Dyke.
a, amorphous trap, columnar at its base; d e, great ochre bed.
Amorphous Basalt below the Ochre bed.
Lign. 8.—Diagrammatic Section of the Coast at the Giant’s Causeway, from the Chimney Head to the Steucan Point; view looking S8.E.
11
Scale, 6 inches to 1 mile for distance and height.
12 THE GEOLOGIST.
first, as the result of vertical pressure applied to the columns after their perfect formation, and before the mass had quite lost its plasticity from heat; secondly, the effect of a re-heating and compression on the columns by an incandescent mass of trap being poured out on them, thus rendering them plastic to a certain depth only, an idea not improbable when it is recollected that basalt fuses at a less heat than that required to melt pig-iron. Near Portrush, on the Coleraine road, an excavation into a low knoll of amorphous trap, the base of which is formed of a thick bed of columnar basalt, affords a striking example of perfectly formed vertical columns being bent over at the top to the depth of a few feet, most likely the re- sult of their having been re-heated and compressed by the super- imposed amorphous trap. The foregoing remarks have of course no reference to columnar masses which exhibit a radiating structure, as this may be merely a rude zeolitic form of columnar arrangement, or crystallization in the basalt.
Leaving the Causeway, and proceeding along the base of the cliffs south west towards the headland called “ Weirs snoot,” (two hundred and eighty-five feet in elevation), we soon pass off the Causeway-bed, as it rises to that direction, or, in other words, slopes to the east- ward; and, as we get near the Hotel, the pathway under the cliffs ex- poses the lost ochre bed of the Chimney-headland ; it is here, however, very thin, and is overlaid by the western extension of the amorphous trap which was described as resting on the “ Organ’’-bed, or that which forms the Giant’s Causeway. The base of this amor- phous trap is rudely columnar to the height of from eight to ten feet from the ochre-bed, the sides of the imperfectly formed pillars being deeply waved or curved, giving them a pinched look. Many of these columns if detached would resemble a long irregularly shaped wedge or pyramid, the base or apex being up or down as chance would have it.
The exceedingly close resemblance of this rudely columnar mass to that of the Rowley Hill, near Dudley, in Staffordshire, is very striking, though they are of different geological age.
The rugged headland to the north of the Causeway Hotel, called | “the Great Steucan,’’ and the cliff called “ Weirs snoot,” are formed — of the amorphous basalts which underlie the ochre-bed, and con-
DU NOYER—-NOTES ON THE GIANT’S CAUSEWAY. 13
sequently in them we have regained the same geological horizon or the beds equivalent to those forming the base of the Chimney-
headland.
From the foregoing ,
remarks we may infer Ist, That lava-flows are much less regular and parallel to each other in their deposition than matter deposited to form an aqueous rock. 2nd, The Basalt which forms the columnar bed known as the “ Giant’s Causeway” is quite a local deposit, measuring at the most two thou- sand six hundred feet in width, or from east to west, and appearing along the coast as alen- ticular shaped bed, thin- ning out at either side; and it occupies a flat- tened trough in the amorphous basalts which underlie the great ochre- bed of the “ Chimney-” headland. 3rd, The section af- forded by the coast ad- joining the Causeway is a cutting transverse to the longest axis of, at least, this lava-flow. 4th, The columns of this particular bed ap-
Lign. 9.—Grouping of Basaltic columns.
Figs. 1 and 2.Three sided columns surrounded by their associated pillars. Fig. 3.—The largest perfect column at the Causeway; a nonagon surrounded by its adjoining pillars. Fig. 4.—Possibly a decagon column, surrounded by nine other columns. It may, however, be merely ahex- agon, and a heptagon attached by one side longer than the others—no means of proving whether the central division e prolonged below the articulation of the pillar shown in
e view.
14 THE GEOLOGIST.
pear to radiate from aline of imaginary centres, which are coincident with the longest axis of the flow; the imner circumference of these radiations being defined by the upper surface of the lava-bed, and hence the upright planes of columnar crystallization strike at right angles downwards from what must have been the primary cooling surface of the mass, that surface from the first having been slightly depressed in its centre.
5th, The columns which form the “Giant's Causeway” exhibit a peculiar beauty and accuracy of form, being in every respect more symmetrical than those of any of the other columnar basalts of the district, with the one exception of the “Organ-”columns, and on this account alone an observer would be led to identify them as be- longing to the same bed.
THE CARBONIFEROUS SYSTEM IN SCOTLAND CHARAC- TERIZED BY ITS BRACHIOPODA.
By Tuomas Davinson, Esq., F.R.S., F.G.S., Hon. Member of the Geological Society of Glasgow, ete., ete.
(Continued from vol. ii., page 477.)
Genus Sprrirera. Sowerby. 1815.
The shells of which this genus is composed differ much in their external shape and appearance, hence the great difficulty of correctly determining the limits of certaim species. The character of this extinct genus are now so well understood that 1t is scarcely necessary to make any further allusion to the subject ; but we may briefly repeat, for the sake of the less initiated, and in order to shorten the descriptions of the various species, that all possess a straight hinge-line, and a triangular or sub-parallel area, which is divided by a triangular fissure, this last bemg more or less covered, or contracted, by the means of one or two curved plates, to which the term pseudo-deltidium has been applied. The pseudo-deltidium is rarely preserved in the carboniferous specimens, but did certainly exist in the perfect or living individuals. The valves are articulated by the means of curved teeth developed on either side of the fissure in the ventral valve, and which fit into corresponding sockets in the opposite or dorsal one. In the larger valve the teeth are supported by vertical fates of greater or lesser dimensions, and in the space between these on the pottom of the shell are situated the muscular impressions. The adductor, or occlusor muscle leaves a narrow mesial oval-shaped scar, and on either side are situated the cardinal, or divaricator muscular nnpressions. In the interior of the smaller, or dorsal yalve there exists two large conical spiral coils, which nearly fill the interior of the shell, the ends being directed outwardly towards the cardinal angles, while the bases of the hollow conical spires nearly meet at
DAVIDSON—SCOTTISH CARBONIFEROUS BRACHIOPODA, 15
the hinge side, but are wide apart in front. The hinge-plate is divided into two portions, to which the principal stems are attached, and in the notch wader the extremity of the umbonal beak there exists a calcareous projection, to which the term “cardinal” process has been applied, and to which was attached one of the extremities of the divaricator muscle. A little lower down, on the bottom of the valve, are seen four large elongated impressions, produced by the adductor, and which have been recently designated as the anterior and pos- terior occlusor muscles by Mr. Hancock.
¥
“lt
S ‘ ‘in! Uhl
chal”
Lign. 5,—Interior of the dorgal valve of Spirifera striata,
All the species referred to the genus Spirifera proper possess a fibrous non- perforated shell-structure.
The species of carboniferous Spirifera that appear to have been hitherto dis- covered in Scotland, are not so numerous as those of England or of Ireland ; and, after a careful examination of many specimens, I could determine with certainty but the nine following :—Sp. duplicicosta, Sp. bisulcata, Sp. trigonalis,
16 THE GEOLOGIST.
Sp. pinguis, Sp. ovalis, Sp. glabra, Sp. Carlukiensis, Sp. Urii, and Sp. lineata ; and it must also be further noted that some of these have hitherto proved exceedingly rare, and that good examples of several others are with difficulty obtained.
VIII.—Spirirera pupticicosta. Phillips. Pl. xii.,* figs. 14, 15.
Spirifera duplicicosta, Phillips, Geol. York., vol. ii., p. 218., pl. x., fig. 1, 1836; and Dav. Carb. Mon., p. 24, pl. iii., figs. 7—10, pl. iv., figs. 3, 5—11.+
This shell varies much in external shape, being either transversely sub-rhom- boidal or somewhat longer than wide. The valves are moderately convex, with a more or less elevated mesial fold in the dorsal, and a corresponding sinus in the ventral one. The hinge-line is shorter than the width of the shell, the area of moderate breadth, and the beak more or less incurved. ‘The valves are orna- mented by numerous radiating ribs, which augment in number at various dis- tances from the beaks by intercalation and bifurcation. The ribs vary, how- ever, somewhat in general appearance in different specimens, being only here and there duplicose, or having three or four ribs clustered together; the term duplicicosta is, therefore, very inappropriate, since many species of the genus present the same peculiarity. Sp. duplicicosta is the largest Scottish spirifer with which I am at present acquaimted, some specimens measuring twenty-one lines in length by about thirty in width; and it has also been sometimes con- founded with Sp. striata of Martin—a closely allied species, but of which I am not acquainted with any well authenticated Scottish example.
Perfect specimens of this shell are rarely found, alikon h thousands of crushed or broken valves occur in a bed of limestone, four feet in thickness, near Campsie, at Balgrochan, and Corrie Burn, in Stirlingshire. In Ayrshire it is found at West Broadstone, near Beith; at Craigie, near Kilmarnock ; and at Auchenskeigh, near Dalry. In Lanarkshire it has been collected at Brockley, near Lesmahago. It has been also found in West Lothian and Bute.
IX.—Sprrirera BisutcaTa. Sowerby. Pl. xii., figs. 19—25.
Spirifera bisulcatus, J. de C. Sow., Min. Con. Tab., 492, figs. 1, 2, 1825; Spirifera bisulcata, Dav. Mon. Carb., p. 31, pl. iv., fig. 1, pl. v., fig. 1, pl. vi., figs. 1—19, and pl. vi.., fig. 4.
This shell is either transversely semi-circular or obscurely sub-rhomboidal, the valves being almost equally deep or convex. The hinge-line is sometimes rather shorter than the greatest width of the shell, with the cardinal angles rounded; or as long, with angles of variable projection. The area is sub- parallel, of moderate width, and divided by a triangular fissure, the beaks meurved, and at times very approximate. In the dorsal valve the fold is some- what angular, and of greater or lesser elevation, but is at times so flattened that it hardly rises above the general convexity of the valve. The sinus is of moderate depth. Each valve is ornamented with from thirty to fifty obscurely- rounded ribs, which increase in number by the occasional bifurcation or inter- calation of smaller ribs at various distances from the beaks. On the mesial fold they are arranged into three groups, separated by sulci of greater depth, the whole surface being also regularly covered with imbricating strie. The variations in shape presented by this species are quite perplexing, and it is probable that several so termed species will require to he added to its synonyms. Among these we may mention Sp. semicircularis, Phillips, and Sp. crassa, de Koninck, certainly ; and possibly Sp. grandicostata of M‘Coy.
* This plate forms part of the second volume of the ‘‘ Gronoatst.”” + For list of synonyms, &c., see my monograph published by the Paleontographical Society, all details not absolutely required haying been omitted in the present monograph.
DAVIDSON—SCOTTISH CARDONIFEROUS BRACHIOPODA. 17
Sp. bisulecata is one of the most abundant of our Scottish spirifers, the largest example with which I am acquainted measuring cighteen lines in length by twenty-eight in width and thirteen in depth. ]
This shell has presented an extensive vertical range; in Lanarkshire it is found at Gare, at a depth of two hundred and thirty-nine fathoms below the horizon of the “Ell coal;” at Races Gillat three hundred and forty-three ; Lang- shaw Burn three hundred and fifty-four ; Mosside three hundred and seventy- three; and at Braidwood Gill three hundred and ninety-seven fathoms. Ure gives us a good figure of a specimen he had found at Lawrieston.* ~ It has been collected at Birkwood, near Lesmahago, and at Robroyston, to the north of Glasgow. In Stirlingshire it is not rare at Craigenglen, Balglass Burn, Mill Burn, Corrie Burn, and in the Campsie main limestone. In Dumbartonshire, at, Castlecary ; in Renfrewshire, at Barrhead, and Arden quarry, Thornliebank ; in Ayrshire,-at Roughwood, and West Broadstone, near Beith; Auchenskeigh, near Dalry; Craigie, near Kilmarnock; Monkredding and Golderaig, near Kilwinning ; and Neathernewton, parish of Loudon, &c. It has also been ob- tained from Arran and Bute.
X.—SPIRIFERA TRIGONALIS. Martin. PI. xii., figs. 16—18.
Conchyliolithus anomites trigonalis, Martin, Petrif. Derb. tab. 36, fig. 1, 1809 ; and Day. Mon. Carb., p. 29, pl. v., fig. 28—33.
In shape it is transversely trigonal, with its hinge-line as long, or slightly shorter, than the greatest breadth of the shell; the area is sub-parallel, and of moderate width, the valves being almost equally deep; the mesial fold is ele- vated, angular, and often produced beyond the frontal margin of the lateral portions of the valve; it is also more often divided by three principal ribs, of which the central one is at the same time the largest and most extended; the sinus is deep, and divided by from three to five longitudinal ribs, of which the central one is also the most developed. Besides these, the surface of each valve is ornamented with from fourteen to twenty-two simple ribs.
This is also a common shell in Scotland, and does not appear to attain the dimensions of Sp. bisulcata, with which it has been sometimes confounded. Dr. Fleming was certainly mistaken when, at p. 374 of his “ History of British Animals,” he referred Ure’s pl. xv., fig. 1, to the species under description.
In Lanarkshire, Sp. ¢rigonalis is found at three hundred and forty-three fathoms below the “Ell coal” at Waygateshaw, and at Braidwood at three hundred and seventy-five. It occurs also at Brockley, near Lesmahago; at Moodies Burn, north-east of Glasgow, and in the main limestone near Camp- sie; and Renfrewshire, at Arden quarry, near Thornliebank; in Ayrshire, at West Broadstone, near Beith ; Craigie, near Kilmarnock ; and at Auchenskeigh, near Dalry. In Midlothian, at Dryden, near Edinburgh; and at Courland, near Dalkeith. It has also been found in West Lothian and in Bute.
XJ.—Srimirera prneuis. Sowerby. Pl. xii, fig. 28.
Spirifera pinguis, Sow. Min. Con., vol. iii., p. 125, tab. 271, 1820; Spirifera pinguis, Dav. Mon. Carb., p. 50, pl. x., figs. 1—12.
When full grown (under favourable circumstances) it is transversely oval, but is also sometimes as wide as long, or even (though more rarely so) longer than wide. The hinge-line is usually shorter than the greatest breadth of the shell, the cardinal angles being rounded, and the area narrow. The dorsal valve is not quite so deep nor so convex as the opposite ; the fold is moderately
* It may be as well to mention that Mr. Bennie has ascertained that Lawrieston is the old name for a place a few hundred yards from the Capel Rig quarry, and now known by the denomination of Brankamhall, East Kilbride.
VOL. III. C
18 THE GEOLOGIST.
wide and produced, smooth, and slightly depressed along its centre. In the ventral valve the sinus is regularly concave and smooth, each valve being orna- mented with from sixteen to thirty rounded or flattened ribs.
This species appears to be rare in Scotland, for I am acquainted with but a single small example, which was derived from carboniferous limestone to the north of Glasgow, and now belongs to the Museum of Practical Geology. measures eleven lines in length by twelve in breadth and ten in depth.
XII.—Sprrirera ovaris. Phillips. Pl. xii, figs. 26, 27.
Spirifera ovalis, Philips, Geol. of York., vol. ii, p. 219, pl. x., fig. 5, 1806; and Day. Mon. Carb., p. 53., pl. ix., figs. 20—26.
This shell is, transversely or elongatedly oval, with a very short hinge-line, and rounded cardinal angles ; the area is triangular, and more often wider than high. The dorsal valve is moderately convex, and much less deep than the opposite one, with a smooth, broad, flattened, mesial fold. In the ventral valve the beak is small, tapering, and incurved; the sinus rather shallow, com- mencing at the extremity of the beak, it extends to the front and is orna- mented with one or two longitudinal ribs placed on either of its sides. From eighteen to twenty simple flattened ribs ornament the surface of each valve. Sp. ovalis appears to be an uncommon species in Scotland, and to which Prof. Fleming, in 1828, had applied the name ezarata ; but as the last named author never figured his shell, and that the description, ‘“ Perforated valve, with broad, smooth, flattened ribs, divided by shallow, narrow furrows; beak gibbous, in- curved; hinge very short,” might apply equally well to several other species, I should question the propriety of adopting the term erarata (notwithstanding its priority of date) in preference to the well-known one by Phillips, an especially so as Dr. Fleming further observes that, although he has frequently found the perforated valve, it was always mutilated or without the other valve, with which he was not acquainted, as may be seen from the original fragment represented in our plate, and which was kindly communicated by the author.
Sp. ovalis has been found in the Corrie Burn beds, Stirlingshire; also in West- Lothian and at West Broadstone in Ayrshire. In Lanarkshire at Brockley, near Lesmahago.
XII1.—Srrriversa GuasBra. Martin. PI. xii, figs. 32—34.
Conchyliolithus anometes glaber, Martin Petrif. Derb., pl. xlvii., figs. 9, 10, 1809, and Dav. Mon. Carb., p. 59, pl. xi., figs. 1—9, pl. xii., figs. 1—5, 11, 12.
This shell varies to such an extent, that it is difficult to assign any perma- nent character; the shape is, however, more often transversely oval, and rarely longer than wide. Both valves differ in degree of convexity, the ventral one being generally the deepest. ‘The hinge-line is shorter than the greatest width of the shell, with rounded cardinal angles and the beak more or less approxi- mate and incurved.
The ventral hinge area is triangular and of moderate dimensions, the dorsal one being narrow and sub-parallel, the mesial fold is either slightly and evenly convex, rising gradually from the lateral portions of the valve, or abruptly elevated with a longitudinal depression along its middle ; the sinus varies like- wise in depth according to the specimens. Externally both valves are gene- rally smooth, but sometimes a few obscurely marked flattened ribs may be observed on the lateral portions of the shell.
This species, at times, attains thirty-two lines in length by forty-three in width, and twenty-six in depth; but no Scottish specimens I have hitherto seen attain half those proportions.
At Harestanes and Langshaw Burn in Lanarkshire, Sp. glabra is found at
DAVIDSON—SCOTTISH CARBONIFEROUS BRACHIOPODA. 19
three hundred and seventy-five fathoms below the “Ell coal ;” occurs also at Middleholm, near Lesmahago and Hast Kilbride. In Stirlingshire at Corrie Burn and Campsie main-limestone. In Renfrewshire at Orchard-quarry, near Thornlicbank. In Ayrshire, at West Broadstone, Beith, and at Auchenskeigh, near Dalry, ete.
XIV.—Sririvera Cartvxrensis. Davidson. Pl. xii, fig. 29.
Spirifera Carlukiensis, Day. Mon. Carb., p. 59, pl. xiii., fig. 14, 1857.
Shell minute, nearly circular and smooth; valves almost equally deep ; dorsal valve regularly convex, most so at the umbone. Ventral valve convex, with a narrow mesial depression or fwrrow commencing at a short distance from the extremity of the beak and extending to the front, where it indents the margin of the opposite valve. The beak is small, pointed, and but slightly incurved ; the hinge-line much shorter than the greatest width of the shell, with its cardinal angles rounded, area small, triangular. This little shell does not appear to have ever greatly exceeded two lines in length by two and a-half in breadth. It was discovered for the first time at Hill Head in Lanarkshire, at about three hundred and fifty-six fathoms below the “ Ell coal,” along with Sp. Urii, but it is a rare species, for in every hundred or more specimens of the last named shell that is collected, a single example of Sp. Carlukiensis would occur. It has also been recently discovered near Strathavon in a bed of shale oe entirely composed of Sp. Urii, and is there nearly as rare as at Hill
ead.
XV.—Spririrera Urn. Fleming. PI. xii, fig. 30.
Spirifer Urii, Fleming, British Animals, p. 376, 1828; Spirifera Urii, Dav. Mon. Carb., p. 58, pl. xi, figs. 13, 14.
This little species is sub-orbicular, and rather wider than long; the hinge- line shorter than the greatest breadth of the shell, and the cardinal angles rounded. The dorsal valve is semicircular and slightly indented in front, with a narrow hinge area; it is nearly flat or slightly convex, especially at the um- bone, from whence a shallow mesial furrow extends to the front. The ventral valve is much deeper and more convex than the opposite one, with a lengthened incurved beak anit longitudinal furrow, which, originating at the extremity of the beak, is continued to the front. The area is small and triangular in shape ; when perfect the exterior of the shell was covered with numerous closely im- planted spines, but which are rarely preserved in the fossil, so that the shell is generally found smooth or covered with minute pustulate markings, which are produced by the fracture of the spines close to their bases.
This abundant and interesting little species was noticed, and figured for the first time by Ure, in 1793, (History of Rutherglen and Kast Kilbride, p. 313, fig. 12.) but named only thirty-five years later by Dr. Fleming. Ure’s figure is not, however, very correct, for it does not represent the incurvature of the beak which is always present, nor is the area ever as wide as is there depicted. Sp. Urii has received several other names, for it is highly probable (if not per- fectly certain) that the Sp. Clannyana, King,* from the Permian formation, and
* The re-occurrence of several carboniferous species in the Permian strata appears to be almost certain, although such has been doubted by several paleontologists. It is therefore probable that the following carboniferous (C), and Permian (P) shells are identical, notwith- standing that they have received distinct specific names according to the strata in which they have been discovered. Thus Terebratula sacculus, 0., = Sp. sufflata,P;? Spirifera Urii, C, = Sp. Clannyana, P ; Spiriferina octoplicata, C., = Sp. cristata, P. ; Camarophoria crumena, C., = 0a. Schlothermi, P.; Ca. globulina, P., = Ca. rhomboidea, P, ; and the Lingula Credneri, P., have been found in the carboniferons strata by Mr. Kirkby. The re-occurrence of species is asubject that has been too often supposed impossible, and treated accordingly.
20 THE GEOLOGIST.
the Sp. unguiculus, Phillips, from the Devonian series, are only synonyms of the present species, and to which must also be added the Sp. Goldfussiana of Prof. de Koninck. It does not appear to have often exceeded about four lines in length by four and a-half in width and two in depth, but is usually a much smaller shell, at least so in Scotland. Sp. Urit is certainly the most abundant of Scottish spirifers, and may be picked up by thousands in several localities, such as at Hill Head, in Lanarkshire, where it occurs at three hundred and fifty-six fathoms below the “ Ell coal,” and three hundred and seventy-five at Kileadzow. It is found plentifully on the east bank of the Avon, near Strath- avon; and at Coalburn, near Lesmahago. In Stirlingshire it has been found in three different stages, viz., the Craigenglen beds, under the main-limestone, and in the black-limestone and shale of South Hill, Campsie.
XVI. Spreirera LinzatTa. Martin. Pl. xii, fig. 31.
Conchiliolithus anomites lineatus, Martin, Petrif. Derb., tab., xxxvi., fig. 3, 1809; and Dav. Mon. Carb., p. 62, pl. xiii, figs. 1—13.
Tn shape this shell is either transversely oval or sub-orbicular, the hinge-line bemg much shorter than the width of the shell, and the cardinal angles rounded ; the beaks are incurved and more or less approximate, the area small. Ventral valve evenly convex, and rarely possessing any mesial elevation, or fold, while the dorsal valve is rather deeper than the opposite one, and either uniformly convex, or presenting a shallow longitudinal depression, which becomes most apparent towards the front. Externally the surface was covered with numerous concentric ridges, rarely in any place more than a line apart, but usually very much closer, and from each of which departed numerous con- tiguous closely packed spines, which thus formed a series of rows, or fringes over the shell. When the spmes are absent, which is the general condition in which the shell is found, the surface appears marked by numerous and regularly imbricated lines, the radiating ones beg produced by the small elevations from which each spine took its birth, as I have attempted to show in the enlarged representation, fig. 31¢, and which is very different from the irregular manner in which the spines are scattered over the surface of Sp. Urit, of which fig. 30e. is an enlarged illustration. Sp. lineata is a common shell in the carboniferous limestone and shales of Scotland; but none of the examples I have yet seen attained the dimensions presented by some which occur both in England and Ireland.
At Gare in Lanarkshire Sp. dizeata occurs at two hundred and thirty-nine fathoms lower than the “ Ell coal ;? at Braidwood, three hundred and forty- three ; at Harestanes, three hundred and seventy-five ; and at Nellfield, four hundred and ten. It may also be collected at Brockley, and Middleholm near Lesmahago. In Ayrshire it occurs at Roughwood, and West Broadstone near Beith; Hallerhirst, Stevenston; and Craigie near Kilmarnock. In Renfrew- shire, at Barrhead; and at Arden and Orchard quarries near Thornliebank. In Dunbartonshire, at Castlecary. In Stirlingshire, under the main limestone and in the Calmy limestone or Balquarhage beds, Campsie, as well as at Corrie Burn. In Mid Lothian it is not rare at Dryden, near Edinburgh; and at Courland, near Dalkeith. Dr. Fleming mentions Dreghorn and Ayr, and it was also found in Arran by Prof. Ramsay.
Sup-crnus Sperrirertna. D’Orbigny. 1847.
The species located in this sub-genus differ from Spirifera (which they re- semble in external shape) by the perforations or canals which traverse their shells, as well as by the development of a large elevated mesial septum in the interior of the ventral valve, to the sides of which was attached the adductor, or occlusor muscle.
DAVIDSON—SCOTTISH CARBONIFEROUS BRACHIOPODA. PAL
Spiriferina cristata vax. octoplicata, and Sp. insculpta are the only two species belongmg to this sub-genus that have been hitherto discovered in our Scottish
carboniferous rocks.
XVII.—SprreivERINA CRISTATA, var. OcToPLIcATA. J. de C. Sowerby. Plate xii, figs. 36-38.
Spirifer octoplicatus, Sowerby, Min. Con., p. 120, pl. 562, figs. 2, 3, 4: 1827. Spiriferina cristata var. octoplicata, Dav. Mon. Carb., p. 38, pl. vil, figs. 37-47.
In external shape this shell is more often transversely sub-rhomboidal, with nearly equally convex valves, the hinge-line being either as long or rather shorter than the greatest width of the shell, with acute or rounded cardinal angles ; the area is triangular, slightly concave, and of variable width. In the dorsal valve the mesial fold is usually composed of a single rib, which is often flattened along the middle; but in some rare examples there exists a rudimen- tary one on either of its slopes, so that in some instances the fold assumes to- wards the front an obscurely biplicated, or triplicated appearance. In the ventral valve the sinus is deep and acute, while both valves are ornamented with from eight to twelve angular ribs, which are (as well as the sinus and fold) closely covered with numerous small granular (spimose) asperities, which give to the shell a rough feel and appearance. The shell-structure is also per- forated by minute tubuli, of which the external orifices may be readily detected by the aid of a common lens. In the interior of the ventral valve a sharp mesial septum rises from the bottom of the valve, and partly divides the spiral cones. ‘The species we are at present describing varies much in general shape, as well as by the number of its ribs; it is never a large shell, although some English specimens have been found more than double the size of any Scottish one that has come under my observation, none of these last having exceeded some six lines in length by about seven in breadth. I am also still inclined to maintain the opinion expressed in my monograph, namely that the shell under description bears so close a resemblance to the Permian Sp. cristata of Schlo- theim that it cannot be specifically separated, and could not in any case claim more than a varietal distinction.
Sp. octoplicata has been found at Gare, in Lanarkshire, at two hundred and thirty-nine fathoms below the “ Ell coal ;” at Braidwood Gill, three hundred ; at Halleraig Bridge, three hundred; and at Raes three hundred and forty-one fathoms. The shell has also been collected in the same county at Brockley, near Lesmahago; Auchtentibber and Calderside, High Blantyre; Capel Rig, Hast Kilbride; Strathavon; and Robroyston, north of Glasgow. in Ren- frewshire, at Arden- and Orchard-quarries, Thornliebank; in Stirlingshire, in the Corrie Burn beds; in Ayrshire, at Roughwood and West Broadstone, Beith; Auchenskeigh, near Dalry; Hallerhirst, Stevenston; Craigie, near Kilmarnock ; and Meadowfoot, near Drumclog. It has also been found in West Lothian, as well as in the Island of Arran.*
* Sp. cristata var. octoplicata is a common shell in the lower red carboniferous sandstone of Kildress ; in Ireland Sp. partita of Portlock being a synonym.
Since the publication of the first pages of my paper in the December number of the “ Grotoaist,” Mr. Kelly has informed me that the quotation at p. 465 relative to the arrange- ment of the Carboniferous system in Ireland does not represent his views, and he has kindly furnished me with the following note.
**My subdivisions are, 1, Old Red Sandstone; 2, calciferous-slate; 3, limestone; 4, coal measures, The Kildress red and yellow sandstone, which is one, is not lower coal-measures ; it lies’’ (as I have stated) ‘‘below the calciferous-slate. Again, the Old Red Sandstone is not that which predominates. This rock averages about one thousand feet thick in Ireland, and is not much exposed, being covered with limestone. Our calciferous slate is considerable in thickness, and in the best developed places (Clonea, near Dungarvan) is half of it made up of thin bands of limestone, the other half calcareous shale. The fossils in both inseparable, so that the calciferous slate and mountain-limestone might be considered as one division, but it
22 THE GEOLOGIST.
XVIII.—Spirtrertma inscutreta. Phillips. PI. xii, fig. 35.
Spirifera insculpta, Phillips, Geol. of Yorkshire, vol. ii., p. 216, pl. ix., figs. 2, 3, 1836; and Dav. Mon. Carb., p. 42, plate vii, figs. 48-55.
In shape it is more or less semi-circular, and about one-third wider than long ; the hinge-area is straight and as wide as the greatest width of the shell. The area large, triangular, and but slightly curved; beak small, and not much produced. Both valves are about equally convex; the ventral one is ornamented with five (rarely seven) large bold angular ribs, of which the central one exceeds the others somewhat in proportion, and corresponds with a deep angular sinus in the opposite valve. All the ribs are sculptured, or closely intersected with small concentric lamin, which give to the perfect shell a very elegant appearance. This is a rare Scottish shell; it occurs at cat Lanarkshire, at two hnndred and thirty-nine fathoms below the “ Ell coal.’
Faminry RuyNcHONELLIDA.
Of this family the genera Rhynchonella and Camarophoria alone have been hitherto discovered in the Scottish carboniferous strata. Of the first we know but two species, and one only of the second ; while in England eight of Rhyn- chonella and three of Camarophoria have been found.
Grunus RuyNcHONELLA. Fischer. 1809.
The shells composing this genus vary much in their external shape and appearance, some being transverse, others rounded or angular, smooth, variously ribbed, or striated. The valves are generally convex, with or without a mesial elevation or sinus; the beak is acute, promment, or so greatly incurved as to touch and even to overlie the umbone of the opposite valve; the foramen is variable in its dimensions and shape, being placed under the extremity of the beak, and entirely or partially surrounded by a deltidium. ‘The shell-structure is fibrous and not perforated; and the valves articulate by the means of two teeth in the ventral, and corresponding sockets in the dorsal valves. The
is perhaps more correct to separate them into two. The Carboniferous, or Hibernian lime- stone is fifty feet thick at Drumguin in Tyrone, it is about fifteen hundred feet thick at Black Head in Clare, and occupies above twenty thousand square miles in Ireland. This greatly predominates ; the coal-measures are two thousand feet thick, or more. The Old Red sand- stone, at Kildress in Tyrone, and the Old Red Sandstone of Herefordshire are two very dif- ferent things. The first belongs to the Carboniferous system; the latter is a subdivision of the Silurian rocks.”
My mistake was not therefore in in the order of superposition of the different strata, which Mr. Kelly admits to be correct; but in having endeavoured to reconcile the succession of the Carboniferous strata in Scotland with that of Ireland by applying Mr. Page’s general denomination of ‘‘ Lower Coal-measures”’ to that group which embraces all the alternations of strata which lie between the Old Red Sandstone and the mountain- or Carboniferous- limestone. The term, however, would not apply to Ireland, since in the sister island no lower coal-measures underlie the mountain-limestone, as we find to be the case in Scotland, and where Mr. Kelly suggests that the limestone may be moved up a stage, with coal- measures below it. It must appear evident to all that the term Old Red Sandstone cannot be retained for a Silurian, Devonian, and Carboniferous rock, and this is the reason why I was, and still am, so averse to applying the term, or forming a subdivision by that name for those Irish red and yellow sandstones full of carboniferous fossils; for if the Calciferous- and mountain-limestone might, according to Mr. Kelly’s own statement, be united into a single division on account of the similarity of their fossils, as a paleontologist, I should add that the same reasoning might equally well apply to the red sandstone of Kildress, for there also we find exactly the same fossils as those which occur in the calciferous and carboniferous- limestone. I should therefore suggest that geologists should drop the term ‘old,’ and in their subdivisions of the Carboniferous group say, 1, Lower carboniferous red and yel- low sandstone ; 2, calciferous slate; 3, carboniferous-limestone; and, 4th, coal-measures, by which means the vexed question relative to the Old Red Sandstone would not be interfered with as far as the Carboniferous system is concerned. It is also well known that Mr. Kelly is of opinion that no Devonian rocks occur in Ireland; while Sir R. Murchison believes that there exists there also a series of many thousand feet of shales and grits above the highest Upper Silurian which represents precisely in time the mass of the Devonian rocks; this, however, has nothing to do with the red and yellow sandstone of Kildress which un- doubtedly forms part of the Carboniferous system,
DAVIDSON—SCOTTISH CARBONIFEROUS BRACHIOPODA. 23
hinge-plate is deeply divided, and supports two slender curved lamelle, to which the spirally coiled fleshy oral arms (directed inwards towards the con- cavity of the dorsal valve) were partially fixed. In the interior of the ventral valve the teeth are supported by dental plates, between which, and extending somewhat further down, are the muscular impressions produced by the adduc- tor or occlusor, the devaricator, and pedicle muscles, while on the bottom of the dorsal valve may be scen the four impressions formed by the adductor, or occlusor muscle. Ovarian markings are observable on either side of the muscular scars above described.
Lign, 6,—Rhynchonella psittacea (recent).
Fig. 2.—Interior of the Dorsal Valve. Fig. 1,—Interior of the Ventral Valve. aa, Adductor, or anterior and posterior oc- | 2, Adductor, or occlusor muscular impression. clusor. vr, Cardinal or divaricator ,, 93 s, Sockets. p, Ventral adjustor “5 of e, Curved lamellew for the attachment of the | 0, Ovarian spaces, oral arms, d, Deltidium, #, Teeth,
XIX.—RuyYNcHONELLA pucNUS. Martin. Pl. i, figs. 1, 2.
Conchyliolithus anomites pugnus. Martin. Petrificata Derbiensia, tab. xxii., figs. 4, 5, 1809; and Dav. Mon. Carb., p. 97, pl. xxii, figs. 1-15.
The shells composing this species are either transversely ovate or oblato- deltoidal, and wider than long. The dorsal valve is usually more or less gibbous, most elevated near the front, and evenly convex at the umbone; the mesial fold is large, and more or less prominent; the ventral valve is less con- vex than the opposite one, with a sinus of moderate depth, commencing at a short distance from the beak, and extending to the front; the beak is small, much incurved, and contiguous to the umbone, each valve being ornamented with from nine to twelve ribs, which become obsolete as they approach the beaks; from three to six occupy the fold and sinus.
All the Scottish examples of this shell that I have hitherto seen were small, none having exceeded eight lines in length by about ten in width, while some English specimens have measured as much as two inches both ways; neverthe- less, the Scottish examples have all the characters of the full-grown shell; but a variety from Carluke parish is comparatively wider and less convex than ano- ther found in Stirlingshire and elsewhere.
At Mosside and Braidwood, in Lanarkshire, R. puyuus is found at three hundred and seventy-five fathoms lower than the “ Ell coal,” also at Brown Hill, near Lesmahago; in Renfrewshire, at Barrhead and Arden quarry, Thorulie-
24, THE GEOLOGIST.
bank; in Ayrshire, at Hyndberry Bank, pe of Loudon, also at West Broad- stone, near Beith; in Stirlingshire, in the main limestone, Campsie, and Mill Burn.
XX.—RuyYNCHONELLA PLEURODON. Phillips. Pl. i, figs. 3—5.
Lerebratula pleurodon, Phillips, Geol. of York., vol. ii, p. 222, pl. xii. figs. 25—30, 1836; and Rh. id., Dav. Carb. Mon., p. 101, pl. xxiii., figs. 1—15.
All the Scottish specimens of this common shell which have hitherto come under my notice, were of small dimensions, and very variable in their shape, but more often transversely oval, and rarely longer than wide. When young the valves were sometimes compressed, but with age became more convex, and at times even gibbous; the beak is small, moderately produced, with a small circular foramen under its angular and slightly incurved extremity, and which is surrounded and a little separated from the hinge-line by a deltidium. The mesial fold usually occupies one-third of the shell, and is most elevated above the front, the smus in the ventral valve being of moderate depth. 'The ribs are angular, and extend over the entire surface of the valves, and vary in num- ber from ten to twenty-four in each valve; of these three to five, and even sometimes nine, compose the fold.
Many undoubted specimens of R. pleurodon possess but three ribs on the mesial fold; and it was for this variety that Professor M‘Coy proposed, in 1844, the name Atrypa triplex, but which is now superfluous.
At Gare, in Lanarkshire, 2. plewrodon is found at two hundred and thirty- nine fathoms under the “ Ell coal,” and three hundred and seventy-five at Braidwood. At Capel Rig, Hast Kilbride, it is very abundant, but nearly every example is crushed; it occurs also at Brockley, near Lesmahago, Calder- side and Auchentibber, High Blantyre. In Dumbartonshire, at Neatherwood, near Castlecary. In Ayrshire, at Hallerhirst, Stevenston; Loudon; Craigie, near Kilmarnock, and West Broadstone, Beith. In Stirlingshire it occurs in several stages: at Craigenglen, Balglass, Mill Burn, Balgrochen, and Corrie Burn. In Renfrewshire, at Barrhead.
Genus CamaropHoriA. King. 1844.
The external shapes and character resemble much those of Rhynchonella. The beak is entire, acute, and more or less incurved, under the extremity of which a small fissure is sometimes exposed. The valves articulate by the means of teeth and sockets. In the ventral valve the dental plates are con- joined at their dorsal margins, forming a trough-shaped process affixed to a low medio-longitudinal plate. In the dorsal valve the space between the sockets is oceupied by a al cardinal muscular protuberance, on either side of which two long slender processes curve upwards, to which were no doubt attached the free cirrated spiral fleshy arms. From beneath the cardinal process a high vertical mesial septum extends to a little more than a third of the length of the valve, supporting along and close to its upper edge a spatula-shaped pro- cess, considerably dilated towards its free extremity, and projecting, with a slight upward curve, to nearly the centre of the shell. Shell structure fibrous, not perforated.
XXI.—Camarorpnoria cRuMENA. Martin. Pl. i, fig. 6.
Conchyliolithus anomites crumena, Martin, Petrif. Derb., tab. xxxvi., fig. 4, 1809; Terebratula Schlotheimi, Von Buch, Ueber Terebratula, 1834; and Day. Mon. Carb., pl. xxv., figs. 3-9.
This species is more often transversely oval, but sometimes also as long, or longer, than wide, aud trigonal in shape. ‘The valves vary in degree of con-
DAVIDSON—ON SCOTTISH CARBONIFEROUS BRACHIOPODA. 25
vexity, as well as in the character of their ribs, which either cover the entire shell, or become obsolete towards the beaks. When perfect, the valves pos-
Lign. 7.—Camarophoria crumena,
Fig. 1.—Interior of the Dorsal Valve. Fig. 2.—Interior of the Ventral Valve.
A, adductor, or occlusor muscular impressions (?); C, curved processes, to which were affixed the fleshy spiral arms; D, deltidium; E, teeth; H, conjoined dental plates or trough- shaped process; J, cardinal process; K, sockets; M, marginal expansions; O, spatula- shaped process, or visceral support ; R, cardinal, or divaricator muscular scars (?) ; 8, septum,
sessed marginal expansions, but which are rarely preserved in the fossil. The mesial fold differs in width and elevation according to the number of ribs which ornament its surface, these varying from two to seven, each valve being fur- nished with from twelve to twenty ribs. The sinus is of moderate depth. Of this species I am acquainted with but a single well-authenticated example, ~ which was Pind many years ago in West Lothian by the late Dr. Fleming.
(To be continued.)
VOL. Il. D
26 THE GEOLOGIST,
BRITISH ASSOCIATION MEETING. (Continued from page 485).
On THE OsstreRous Caverns at Oreston. By Henry C. Hodge, of Plymouth, Read before the Geological Section, Sept. 17, 1859.
The constant removal of immense masses of limestone required for the pur- poses of the Breakwater at Plymouth, during the past half century, has from time to time brought before the attention of geologists a series of remarkable cavernous fissures of great interest, from the number and variety of fossil remains of extinct animals contained in them.
In the “ Philosophical Transactions” for 1817, 1821, and 1823, will be found some account of the earliest discoveries of these fossils, together with a record of carefully conducted observations by Sir Everard Home and Mr. Whidby (the engineer of the Breakwater at that time) respecting the eireum- stances under which they were met with.
Mr. Whidby, in a paper dated Nov. 1816, mentions the striking fact that he saw no possibility of the cavern in which the remains were met with having had any external communication through the rock in which it was enclosed, the surrounding limestone being everywhere equally strong, and requiring the same labour to blast it; and, with respect to the occurrence of stalactite, he remarks that nothing of the kind was met with in the cavern in which the bones were found, so that there is no proof that any opening in the rock from above had been closed by infiltration. In the year 1820 more bones were met with, lying on a thin bed of dry clay; there also occurred here and there a few small caverns, similar to that m which the bones were discovered; and again he states that none of them had the smallest appearance of ever having had any opening to the surface, or connection with it whatever, or with each other. The caverns here spoken of were quarried many feet below the bottom of them, and nothing was found but hard solid limestone. He also adds, “that many caverns have been met with in these quarries, the insides of which have been coated with stalactite; but there was no appearance of this kind in the cavern where the bones were found, every part of it being perfectly dry, and nearly clear of rubbish—a circumstance which clearly proves it had no connection with the surface.”
During the summers of 1822-23, Mr. Jos. Cottle, of Bristol, obtained a large collection of bones from the same quarries, and he has published some account of them, and of the general circumstances of their occurrence.
Since that period, it would appear that similar openings in the limestone have been of not unfrequent occurrence, and it is known that some of them have contained fossils; but no systematic observations have, I believe, been instituted with the view of penetrating their origin or history.
The statements so confidently made by Mr. Whidby as to the perfect enclosure of the caverns by solid limestone, have been confirmed by my own observations, and this fact has not failed to surprize even the workmen engaged in the quarry; but it must be evident that at some period an opening did exist, and it occurred to me that such might be most successfully sought for between the surfaces of the beds of which the masses of limestone are composed. No satisfactory conclusion could be drawn from a careful examination of the rock
BRITISH ASSOCIATION MEETING, 27
during the opening of the cavern; but, on looking narrowly at the beds of limestone in the progress of the workings, it was found that a thin seam of purple calcareous “slate” was interposed between the beds of limestone, at about the same parallel as that in which the caverns were met with. On fur- ther investigation, it was discovered that alternations of this purple “slate” with the limestone were not unfrequent, but the laming of slate were, in most cases, so intimately blended with the limestone-beds, as to form really a solid mass of compact rock ; and on looking into the structure of the more evident layers of the “slate,” it was ascertained that in some parts they were much more calcareous than in others, and that small portions of limestone, havin, similar physical characters to those of the surrounding rock, were intersperse: at varymg intervals. In other places the layers were in a state of decomposi- tion, red and reddish white clay being formed as its result; and on tracing a layer of this kind through the side of a cavern laid open during the workings, it was seen that portions of it were so disintegrated as to be easily pulled from their position, the seam being, in its most solid portions, composed merely of layers of limestone-fragments with interposed clay and red sand—the whole, apparently, kept in place by the accidental infiltration of calcareous matter. Here, then, were facts that might enable me to account for the clay found in the caverns, and afford a means through which the beds of limestone may have been caused to separate from each other. Again, it was discovered that some of the hollows in the adjoining limestone were stained with a black earthy sub- stance, found, on analysis, to be composed of the peroxides of iron and man- ganese, these having evidently proceeded from the decomposition of a variety of dolomite very generally present in this limestone—not exhibiting, however, any definite mode of deposit in it, but passing through its beds in the most irregular manner. From these phenomena, it appeared reasonable to conclude that the decomposition of the “slate” in the layers, through the combined agency of water and carbonic acid, had opened a communication with the external air to the above-named irregular masses of dolomite (the unchanged limestone-fragments of the “slate” serving to keep the beds from close contact with each other), and that in this way the carbonates of iron and manganese contained in them had been converted into peroxides, and the evolved carbonic acid proceeding from their decomposition, combining with the remaining consti- tuents of the dolomite, had formed bicarbonates, readily removeable by the agency of percolating water. In this way it is possible, not merely to account for the formation of the caverns, and a means of access to them, but at the same time to discover what are the causes still in operation which give rise to the production of stalactite, and occasion the irregular dolomization of the lime- stone, it being evident that the percolating waters, charged with bicarbonates of lime, magnesia, &c., may, by a loss of carbonic acid, deposit insoluble car- bonate of lime in the form of stalactite, and becoming by this means richer in bicarbonate of magnesia, act chemically on the neighbouring limestone, convert- ing it into dolomite.
To test the correctness of these views, a very careful examination of the clay below the bones was instituted: it was extremely tenacious, and of a dark reddish-brown colour; patches of red clay were visible in some places, and in other parts of the mass distinct yellow and black layers were apparent, and nodules, or, more strictly speaking, irregular masses of impure oats red iron- . ore, together with black, rounded fragments, evidently arising from the decom- position of a dolomite similar to that before alluded to—for in the larger frag- ments this rock was distinctly visible on fracture, and in one or two instances, in which the masses were larger than usual, a brown zone was observable between the black external coating and the central nearly unaltered dolomite ; large and small masses of the common limestone-rock of the quarry were also
28 THE GEOLOGIST.
found in the clay, their surface being honey-combed as if by exposure to the long-continued action of carbonated waters. These phenomena may justly be explained on the supposition, that the irregular masses of ochry iron-ore had been derived from the decomposed slaty seams, confirmatory appearances being not unfrequent in other limestone-beds connected with the same series of rocks, the “slate” in these alternating with the limestone on a large scale, and con- taining eur iten nodules of impure iron-ore—a red oxide of iron being fre-
uently visible at the pomts of junction. The varied colour of the clay may
so be accounted for by the gradual admixture with it of the red oxide of iron from the slaty seams, and the black oxide of manganese, accompanied by yellow hydrated peroxide of iron from the dolomitic rock, which may be concluded to have formed a part only of the walls of the cavern—the honey-combed lime- stone fragments resulting from the displacement of other portions of previously fissured limestone-rock through the agency of aqueous carbonic acid. The most careful examination presented no facts that at all appeared of an opposing character ; the clay was diligently searched, and some of its laminated portions, having a sandy appearance, were examined by the microscope for the siliceous coverings of infusoria, minute rounded grains of sand, and any other matter that might suggest the washing in of the contents of the cavern through free communication of its opening with external waters; nothing was, however, discovered but very minute fragments of slate, still further confirmatory of the position before advanced.
The facts elicited were thus far satisfactory, but they did not account for the original production of those masses of dolomite, which in the neighbour- hood of the quarry, alone afforded, by their own decomposition, the solution of bicarbonates required for the dolomization of adjacent rocks: and in the hope that a knowledge of such original cause might throw still further ight upon the present condition of the bone-caves, a general examination of the various accessible quarries of the Plymouth limestones was instituted.
I propose to give some account of these investigations in the latter part of this paper; and will now proceed to give a brief description of the fossil re- mains, and certain circumstances connected with them, as the following out of the inquiries alluded to will lead me to speak, not merely of changes having an important relation to the phenomena of the enclosed caverns, but also to the attempted solution of other allied geological questions of interest.
I am disposed to believe that very little stalactite was deposited in the bone- caves during the early period of their formation, and a portion, if not the whole, of the time durmg which the bones were being introduced. My reasons, confirmed by the observations of Mr. Whidby, before alluded to, are the fol- lowing :—The bones have been generally found lying on or near the uppermost portion of a bed of clay, and those on its surface only are much mixed with, or imbedded in stalagmite, the remains met with lowest in the clay being especiall free from such deposit. It is reasonable also to suppose that, if the fossil bones were introduced through the agency of carnivorous cave-inhabiting mam- malia, the instincts of these creatures would have induced them to prefer a dry habitation, and one in which the constant dropping of percolating waters would
ive them no inconyenience, not to mention the constant disengagement of car- Fonte acid accompanying the deposition of the stalactite, which might even, _ under some circumstances, render such caverns uninhabitable.
In giving an opinion that the bones were introduced by animal agency, and not by accidental falling into fissures, it is not to be inferred that, in no former recorded instance, has this mode of entombment occurred. I will, however, give some facts connected with the nature and mode of occurrence of these re- mains, before attempting to deduce any further conclusions in the present instance.
BRITISH ASSOCIATION MEETING. 29
In the first, I would mention that remains of very large animals were met with, the occurrence of portions of several mammoths being proved by the pre- sence of various grinders belonging not merely to very young, but also to some- what mature animals, a fourth molar of the lower jaw of an animal of this species having been found six and a-quarter inches in length, the breadth at its widest part being two and a-quarter inches, containing sixteen plates, which have all been brought into use, the tooth bemg worn down at its anterior ex- tremity, so as to exhibit the common uniting base of dentine along the margins of the first and second plates. A second corresponding molar of the lower jaw wanting a few plates at its anterior portion, together with fragments of two other fourth molars in different stages of development were also met with, and teeth of larger size than these were indicated by the presence in the clay of other detached and fractured plates. I would also add that there occurred a few fractured portions of one or more molar teeth of the rhinoceros, but no mammoth’s or other large bones were discovered.
The above facts being considered, can we allow that such ponderous animals could have fallen upon a soft tenacious bed of clay, without simking more than a few inches into it ? or that their skeletons could have been washed down from above, without a much greater disturbance of the clay than was found to be indicated by the parallel and undisturbed arrangement of its laminated por- tions? Could, moreover, these monsters have fallen into the cavern, without a much greater apparent disturbance of the beds of limestone having been caused by the formation of a sufficiently large opening; and would not, in such cases, numerous other parts of the skeleton have been met with ?
Secondly, numerous teeth of elk or deer and of ox were found, but no antlers nor horn-cores belonging to such animals (a single fragment of the base of an antler and one small horn-core excepted), which would, most pro- bably, have been the case, had the fissure beena large one, and some fragments, at least, of the fragile antlers might naturally have been expected to occur, had such been washed down from a higher level; on the other hand, it may be pre- sumed that they would have proved to carnivora an inconvenient and unprofit- able burthen for carriage into their den.
Thirdly, among the bones met with, scarcely a single large one had escaped fracture, with the exception of the astralagus and other hard and solid bones of the tarsus and carpus joints and those of the feet; facts perfectly similar to those observed by Dr. Buckland in the hyena-cave at Kirkdale, in which the presence of their numerous coprolites proved that these animals inhabited the cavern.
Fourthly, although the cave did not contain any remains of hyenas or their coprolites, several teeth of bears and lions or tigers were discovered; and I think it may be legitimately deduced from the occurrence of these cave- inhabiting animals that the bones above referred to had been fractured by them for the purpose of obtaining their edible contents ; the occurrence of several fragments of canines of the gigantic Felis spelea having the two characteristic longitudinal indentations on their crowns, together with the canine and sectorial molar of an immense lion or tiger, the former tooth measuring five and three- quarter inches im length, may too, I imagine, satisfactorily account for the strength required to carry the remains of such animals as the mammoth and rhinoceros into the cave.
Lastly, I would remark that the view of the non-accidental introduction of the remains into the cave appeared still further to be confirmed by the appear- ances presented in a fissure unexpectedly opened into by the workmen, and separated from the larger cavern by a comparatively thin wall of solid limestone. Here many of the bones were only slightly fractured, and there occurred the nearly perfect skull of a hog, encrusted with stalactite, a cast in the same sub-
30 THE GEOLOGIST. ;
stance of the interior of the cranium of another animal, together with remains, apparently belonging to the bear, wolf, or large dog, and the horse, with various other fractured bones cemented into a breccia-like mass by a mixture of clay and stalactite. These appearances coincide with what might have been ex- pected to have occurred in the case of bones that had accidentally fallen into a fissure, and it is not unlikely that they may have been rolled into it through a small deep hole communicating with the large cavern, but not sufficiently capacious to allow of entrance for the recovery of the carcass. The brecciated - bones in the clayey stalactite might have been also derived from the larger cave by the constant falling into it of fragments of bone rejected by the carni- vora, and which, as might he expected from lying for some time in their den, would be well mixed with the clay that formed its bottom.
A few of the bones were traversed in all directions by fissures filled with clayey stalagmite, amass composed of broken plates of a tooth of the mammoth being in this condition—these facts possibly indicating displacement of the walls of the cave after the introduction of the bones, such dislocation affording the opening, by means of which the superficial stalagmite was introduced.
In concluding this part of my description of the caverns and their inhabitants, J will enumerate the genera of animals to which the specimens (nearly all of which are in my own possession) belong.
(To be continued.)
PROCEEDINGS OF GEOLOGICAL SOCIETIES.
GroLocicaL Socipty or Lonpon.—November 30, 1859.—Professor John Phillips, President, in the Chair.
The following communications were read :—
1, “On some Bronze Relics from an Auriferous Sand in Siberia.” By T. W. Atkinson, Hsq., F.G.S.
During the author’s stay at the gold-mine on the River Shargan (Lat. 59 deg. 30 min. N., and Long. 96 deg. 10 min. EK.) in August, 1851, some frag- ments of worked bronze were dug up by the workmen, at a depth of fourteen feet eight inches below the surface, from a bed of sand in which gold-nuggets occur. This sand rests on the rock, and is covered by beds of gravel and sand, overlain by two feet of vegetable soil. The fragments appear to have belonged either to a bracelet or to some horse-trappings.
2. “On the Volcanic Country of Auckland, New Zealand.” By Charles Heaphy, Esq. Communicated by the President.
The isthmus-like district of Auckland and its neighbourhood, described by Mr. Heaphy as a basin of Tertiary deposits, is bordered by clay-slate, igneous rocks, and at one spot on the south by cretaceous strata; and it is dotted by upwards of sixty extinct volcanos, often closely situated, and showing in nearly every instance a well-defined point of eruption, generally a cup-like crater, on a hill about three hundred feet high. Interesting instances of sue- cessive volcanic eruption are numerous all over this district, sixty miles round Auckland; and there seems to have been four distinct epochs of eruption, thus classified by Mr. Heaphy :—1. The first was that which raised the trachytic
PROCEEDINGS OF GEOLOGICAL SOCIETIES. 31
mountains and the black boulder-like igneous rock. 2. Then came the erup- tions in the Tertiary period, the ashes of which form beds in the Tertiary rock. 3. Then the eruptions on the upheaval of the Tertiary cliffs : these appear as cones above faults on the Tertiary beds and on the edges of cliffs. 4. Lastly the eruptions that have broken through the Tertiary beds, and the lava-streams of which follow the natural valleys of the country. The volcanic phenomena were illustrated by maps and numerous sketches by the author. Some Ter- tiary Zerebratule, some few fossil plants, and some Cretaceous fossils (Znocera- mus and Belemnitella) accompanied this memoir.
3. “On the Geology of a part of South Australia.’ By T. Burr, Esq. From the Colonial Office. 1848. ;
The lowlands about Adelaide on the west, and along the river Murray on the east, consist of horizontal beds of limestone and calcareo-siliceous deposits, yellowish and reddish in colour, full of marine fossils, and of the Tertiary age. Sometimes gypsum and ferruginous sand replace the limestone. These plains are arid, except where granite protrudes from the surface, presenting cavities in which rain-water collects. The author observed a similar Tertiary forma- tion on Yorke’s Peninsula, at Port Lincoln, and to the 8.E. to beyond Rivoli Bay ; and it probably forms vast tracts in New South Wales and Western Australia. Tone of these tertiary districts appear to exceed an elevation of three hundred feet above the sea.
In describing two volcanos in South Australia, Mount Gambier and Mount Schauck, Mr. Burr remarked that, coming from the west or north-west at about twenty miles from these hills a white coral-limestone (Bryozoan limestone), contaiming flint or chert, takes the place of the limestones and calcareous sandstones, with recent sand-formations, previously passed over. This white limestone is remarkable for the numerous deep well-like water-holes in it, within about twelve miles of the volcanic mountains, and about east or west of them.
Mount Gambier has a height of nine hundred feet above the sea (six hun- dred feet above the plain), and has three craters, lying nearly east and west, and occupied with lakes of fresh-water. Mount Schauck, at a distance of about nine miles, magnetic south, is circular, and has one large, and two small lateral craters.
The author next described the granite, gneiss, and slaty rocks along a sec- tion extending from the River Murray and Kangaroo Range, across Mount Barker and Mount Lofty, towards Adelaide; and noticed the mode of occur- rence of the ores of copper, iron, lead, &c., in these rocks. Lastly he noticed and explained the occurrence of calcified stems of trees, standing in the posi- tion of their growth, in the sand-dunes in the Gulf of St. Vincent, near Adelaide.
4. “On some Tertiary deposits in South Australia.” By the Rev. Julian Edmund Woods. Communicated by the President.
The author, in the first place, described the geographical features of that pe of the colony of South Australia to which his observations refer, It lies
etween the River Murray on the west, and the colony of Victoria on the east ; and includes an area of one hundred and fifty-six miles long, north and south, and seventy broad from east to west. Some trap-dykes and four volcanic hills are almost the only interruptions to the horizontality of these plains, which rise gradually from the sea, and are occupied by the Tertiary beds ee tice; they extend into Victoria for some seventy miles, as far as
0 ‘
In some places on the plains a white compact unfossiliferous limestone lies under the surface-soil; and is sometimes thirty-feet thick. Under this is a
fossiliferous limestone. The passage between the two is gradual. This latter
32 THE GEOLOGIST.
rock is made up of Bryozoa—perfect and in fragments—with some Pectens, Terebratule, Echinoderms, &e.
Sometimes this rock appears like friable chalk, without distinct fossils. A large natural pit, originating from the infalling of a cave, occurs near the ex- tinct voleano, Mount Gambier, and is ninety feet deep, showing a considerable thickness of this Bryozoan deposit in several beds of fourteen feet, ten feet, and twelve feet in thickness. Similar pits show the deposit in the same way at the Mosquito Plains, seventy miles north.
Regular layers of flints, usually black, rarely white, occur in these beds, from fourteen to twenty feet apart. ‘These, with its colour, and with the superficial ee perforating the rock to a great depth, give it a great resemblance to chalk.
The whole district is honeyecombed with caves—always, however, in the higher grounds in the undulations of the plains.
One of the caves, in a ridge on the northern side of the Mosquito Plains, is two hundred feet long, is divided into three great halls, and has extensive side- chambers. The caves have a north and south direction, like that of the ridge. The large cave has a great stalactite in it; and many bones of Marsupialia are heaped up against this on the side facing the entrance; possibly they may have been washed up against this barrier by an inflowing stream. The dried corpse of a native les in this cave. It has been partially entangled in the stalactite ; but this man was known to have crept into the cave when he had been wounded, some fourteen years ago. Many of the caves have great pits for their external apertures, and contain much water.
Some shallow caves contain bones of existing Marsupialia, which have evidently been the relics of animals that fell into the grass-hidden aperture at top.
The caves appear in many caves to be connected with a subterranean system of dramage; currents and periodical oscillations being occasionally observed in the waters contained in them. ‘There is but little superficial drainage. One overflowg swamp was found by the author to send its water into an under- ground channel in a ridge of limestone.
Patches of shelly sand occur here and there over the ten thousand nine hun- dred and eighty square miles of country occupied by the white limestones; but near the coast this shelly sand thickens to two hundred feet.
A coarse limestone forms a ridge along the coast-line, and it contains exist- ing species of shells. This indicates an elevation of the coast of late date, and which probably is still taking place.
Dec. 14.—1. “On some Remains of Polyptychodon from Dorking.” By Prof. Owen, F.R.S., F.G.8.
Referring to the genus of Saurians which he had founded in 1841 on certain large detached teeth from the Cretaceous beds of Kent and Sussex, and which genus, in reference to the many-ridged or folded character of the enamel of those teeth, he had proposed to call Polyptychodon, Prof. Owen noticed the successive discoveries of portions of jaws, one showing the thecodont implanta- tion of those teeth, which, with the shape and proportions of the teeth, led him to suspect the crocodilian affinities of Polyptochodon ; and the subsequent discovery of bones in a Lower Greensand quarry at Hythe, which, on the hypo- thesis of their having belonged to Polyptychodon, had led him to suspect that the genus conformed to the Plesiosauroid type.
The fossils now exhibited by Mr. G. Cubit of Denbies, cofsisted of part of the cranium (showing a large foramen parietale), fragments of the upper and lower jaws, and teeth of the Polyptychodon interruptus, from the Lower Chalk of Dorking, and afforded further evidence of the plesiosauroid affinities of the genus. Professor Owen remarked that in a collection of fossils from the Upper
PROCEEDINGS OF GROLOGICAL SOCIETINS. 33
Greensand near Cambridge, now in the Woodwardian Museum, and in another collection of fossils from the Greensand beds near Kursk in Russia, submitted to the Professor’s examination by Col. Kiprianolf, there are teeth of Polyptycho- don, associated with plesiosauroid vertebra of the same proportional magnitude, and with portions of large limb-bones, without medullary cavity, and of plesiosauroid shape.
Thus the evidence at present obtained respecting this huge, but hitherto problematical, carnivorous Saurian of the Cretaceous period seemed to prove it to be a marine one, more closely adhering to the prevailing type of the Sea- lizards of the great mesozoic epoch, then drawing to its close, than to the Mosa- saurus of the Upper Chalk, which, by its vertebral, palatal, and dental charac- ters, seemed to ET dor the Saurian type to follow.
Professor Owen exhibited also drawings of specimens in the Woodwardian Museum and in the collection of Mr. W. Harris, of Charing, which show the mode and degree of use or abrasion to which the teeth of Polyptychodon had been subject.
2. “On some Fossils from near Bahia, South America.” By 8. Allport, Esq. Communicated by Professor Morris, F.G.S.
The south-west point of the hill on which the Fort of Montserrate is built, in Bahia Bay, exhibits a section of alternating beds of conglomerate, sandstone, and shale; im the last Mr. Allport discovered a large Dinosaurian dorsal verte- bra, not unlike that of Megalosawrus, several Crocodilian teeth, and numerous large scales of Lepidotus, together with a few Molluses (Paludina, Unio, &e.), some Hntomostraca, and Lignite. Two miles from Montserrate, in a N.H. _ direction, is the Plantaforma, another hill of the same formation, but loftier. The shales here also yielded similar fossils.
These fossiliferous shales and conglomerates dip to the N.W. towards the Bay, and appear to overlie a similarly inclined whitish sandstone, which rests against the gneissose hills ranging north-easterly from the point of St. Antonio.
3. “On a Terrestrial Mollusc, a Chilognathous Myriapod, and some new species of Reptiles, from the Coal-formatian of Nova Scotia.’ By J. W. Dawson, L.L.D., F.G.S., &e.
On revisiting the South Joggings in the past summer, Dr. Dawson had the opportunity of examining the interior of another erect tree in the same bed which had afforded the fossil stump from which the remains of Dendrerpeton Acadianum and other terrestrial animals were obtained in 1851 by Sir C. Lyell and himself. ‘This second trunk was about fifteen inches in diameter, and was much more richly stored with animal remains than that previously met with. There were here numerous specimens of the land-shell found in the tree pre- viously discovered in this bed—several individuals of an articulated animal, pro- bably a Myriapod—portions of two skeletons of Dexdrerpeton—and seven small skeletons belonging to another Reptilian genus, and probably to three species.
The bottom of the trunk was floored with a thin layer of carbonized bark. On this was a bed of fragments of mineral charcoal (having Sigillaroid cell- structure), an inch thick, with a few Reptilian bones and a Sternbergia-cast. Above this, the trunk was occupied, to a height of about six inches, with a hard black laminated material, consisting of fine sand and carbonized vegetable | matter, cemented by carbonate of lime. In this occurred most of the animal remains, with coprolites, and with leaves of Noeyyerathia (Poacites), Carpo- lithes, and Calamites, also many small pieces of mineral charcoal, showing the structures of Lepidodendron, Stigmaria, and the leaf-stalks of Ferns. The upper part of this carbonaceous mass alternated with fine grey sandstone, which
led the remainder of the trunk as far as seen. The author remarked that this tree, like other erect Sigillarie in this section, became hollow by decay,
VOL. Il. E
34 THE GEOLOGIST.
after having been more or less buried in sediment; but that, unlike most, others, it remained hollow for some time in the soil of a forest, receiving small quantities of earthy and vegetable matter, falling into it, or washed in by rains. In this state it was probably a place of residence for the snails and myriapods and a trap and tomb for the reptiles ; though the presence of coprolitie matter would seem to show that in some instances at least the latter could exist for a time in their underground prison. The occurrence of so many skeletons, with a hundred or more specimens of land-snails and myriapods, in a cylinder only fifteen inches in diameter proves that these creatures were by no means rare in the coal-forests ; and the conditions of the tree with its air-breathing inhabitants implies that the Sigillarian forests were not so low and wet as we are apt to imagine.
The little land-shell, specimens of which with the mouth entire have now oc- curred to the author, is named by him Pupa vetusta. Dr. Dawson found entire shells of Physa heterostropha in the stomach of Menobranchus lateralis, and hence he supposes that the Pupe may have been the food of the little reptiles, the remains of which are associated with them.
Two examples of Spirorbis carbonarius also occurred ; these may have been drifted into the hollow trunk whilst they were adherent to vegetable fragments. The Myriapod is named Xylobius Sigillaria, and regarded as being allied to Lulus.
The reptilian bones, scutes, and teeth ideatle to Dendrerpeton Acadianum bear out the supposition of its Labyrinthodont affinities. Those of the new genus, Hylonomus, established by Dr. Dawson on the other reptilian remains, indicate a type remote from Archegosaurus and Labyrinthodon, but in many respects approaching the Lacertians. The three species determined by the author are named H. Lyellit, H. aciedentatus, and H. Wymani.
4. “On the Occurrence of Footsteps of Chirotherium in the Upper Keuper of Warwickshire.” By the Rev. P. B. Brodie, F.G.S.
True Chirotherian feetsteps do not appear to have been hitherto met with in the Keuper of Warwickshire; but a specimen of Keuper sandstone showing the casts of a fore- and a hind-foot of Chirotherium was lately turned up by the plough at Whitley Green, near Henley-in-Arden. The breadth of the fore-foot is about two inches, the hind-foot is four and a-half inches across. As the New Red sandstone of Cheshire, so well known for its fine Chirotherian foot- tracts, certainly belongs to the upper part of the New Red series, it may now be further correlated with the Upper Keuper of Warwickshire, the latter having yielded true Chirotherian foot-prints.
Guotocist’s Assoctation, Ordinary Meeting, 5th Dec., 1859. Rev. Thomas Wiltshire, M.A., F.G.S., President, in the chair.
The president stated that since the last meeting the Association had lost a valuable friend in the person of John Brown, Esq., F.G.S., who had prepared a paper which was to have been read that evening. Under these circumstances the committee had thought it respectful to the memory of Mr. John Brown, that his paper (which had been forwarded to the president) should not be read until the next meeting in January. It was announced that Professor Tennant, — F.G.S., had kindly volunteered at very short notice to give a lecture on siliceous nodules in the various formations.
Professor Tennant commenced by some observations on the large proportion in which silica enters into the composition of rocks, constituting one-half part — of granite, one-third part of syenite, nine-tenths of quartz, and three-fourths of — greensand. He then described the enormous amount of silica in the flints of the upper chalk, and called attention to the peculiarity which distinguishes the beds of flints in Kent and Sussex from those of Yorkshire. In the former they
PROCEEDINGS OF GBOLOGICAL SOCIETIES. 35
are of dense structure; in the latter mostly of a porous character, taking regular forms, not unlike those of many modern sponges.
Some remarks were then made on Dr. Bowerbank’s theory that the great mass of the flints found in the chalk are true sponges : a theory to which Pro- fessor Tennant said he was inclined to subscribe. He pointed out as an illustra- tion of its possible truth, and as a proof that organic remains may be enclosed in ‘silica, the well known appearance of moss-agates, sections of which, procured from Oberstein, cannot under the microscope be distinguished from sections of
~ certain modern sponges. Professor Tennant also drew attention to the differ- ence in the flints of volcanic and aqueous rocks; the former being destitute of, whilst the latter abound in, organic remains.
After alluding to the beds of chert in many of the formations, such as the Portland-rock, Greensand, ete., he advocated the view that the Paramoudra, of Treland, are nothing more than enormous silicified sponges, and concluded with an account of the hollow flints found on Salisbury Plain, the core of which when examined under the microscope is seen to be composed of a mass of delicate spicules.
A discussion by several of the members followed, during which the president directed attention to a circumstance, which Mr. Charlesworth confirmed, viz., that a mass of flint when surrounding the base of a ventriculite, never en- velopes the whole of the root of the ventriculite.
Mr. Charlesworth made several remarks, with a view of explaining this phe- nomenon, and at some length entered into reasons for disagreeing with the views of Dr. Bowerbank as to the spongous origin of many of the Chalk flints.
The late Mr. John Brown, F.G.S., of Stanway, has bequeathed the sum of £100 to the Association.
Matvern Fretp Cxius.—The Naturalists’ Field Club lately held a meeting at Pershore, on which occasion the President, the Rev. Mr. Symonds, of Pen- dock, addressed the meeting at some lerigth upon a few of the most important scientific topics of the day. On the subject of the supposed flint implements which have caused so much disquisition among aooletatst Mr. Symonds re- marked that they were discovered in the north of France, in undisturbed beds of gravel, sand, and clay, in drift, in fact, of much the same geological age as the old lake- and river- margins of the Avon, the Severn, and the Wye. The level of the land in that part of France, however, appears to have been more deranged by oscillating movements than has been the water-level of the peace- ful vales of Worcestershire and Herefordshire. The stratified gravel, contain- ing the weapon-looking flints, associated with the remains of the extinct ele- phant and rhinoceros, occupies, in some localities, a height of one hundred feet above the present level of the river Somme, which has worn for itself a newer and deeper bed since those flints and the bones of wild beasts were buried together in the mud, silt, and gravel of its ancient margins. On the question of the human fabrication of the flints, Mr. Symonds said that he had seen many exhibited at Aberdeen, by Sir Charles Lyell and Mr. R. W. Mylne, and that the rudeness of many of these implements might well cause the cautious inves- tigator of truth to pause before he believed that they were wrought by men; while on the other hand some of the specimens appeared to have been so wrought. The question rested, from the evidence Mr. Symonds could collect, on the fact as to whether or not the flints were human implements. The re- mains of the extinet mammalia may have been drifted from older beds, but the physical geology of the district, and the physical position of the stratified drifts, containing the supposed human implements, compelled the most able of the geologists of France aud England to arrive at the conclusion that, if these flints
36 THE GEOLOGIST,
are human implements, man lived at a far more remote epoch than has usually been assigned to his creation.
The Pteraspis discovered at Leintwardine, near Ludlow, by Mr. Lightbody, of the Woolhope Club, in the Lower Ludlow deposits, greatly antedated the period at which fish were supposed to have first existed. The fossil had been examined by competent authorities and both its fish character, and the physical position of the beds, had now been firmly established. After the meeting of the British Association of Aberdeen, Mr. Symonds accompanied Lord Ennis- killen, Sir C. Lyell, Sir W. Jardine, and Professor Harkness to the Elgin dis- trict, for the further examination of the reptile-bearing sandstones containing the Telerpeton, Stagonolepis, and Hyperadaphodon, and long supposed to belong to the age of the Old Red Sandstone. Mr. Symonds entirely agreed with the opinion formed by Sir C. Lyell, founded on a mass of evidence and details too intricate to be briefly or easily explained, that the reptiliferous sandstones of Elgin are more probably of the Triassic age, than of the epoch of the Old Red.
NOTES AND QUERIES.
Notices of INcORRECTNESSES IN Mr. Pacn’s HanpBoox or GEoLocicaL Trerms.—Derar Srr,—On the recommendation of last month’s “ Gnonoeist,” LT bought Mr. Page’s Handbook of Geological Terms. Upon glancing at it, I saw that he had fallen into some errors of pronunciation, and, invited to do so by his preface, I wrote to him immediately to put him on his guard, and give lum an opportunity of taking such steps as he should deem advisable. As the matter seems to have escaped your notice, I think it well to advise you of it. In my opinion there are many of these errors; but others may differ from me in some instances. I note a few, however, below, which admit of no doubt, as reference to every lexicon and received authority will show :
Affinis, Agelitinans, Albo-galérus, Briaréus, Concavus, Céngeners, Echinus and Echinite, Edulis, Huglyphus, Gigantéus, Hexagénus, Hippocrépis, Ma- crospondylus, Mammilliferons.
One or two other errors of a different kind, have caught my eye.
Miliola he derives from mille—though confounding the idea with that of pupids, 10,000, apparently. It evidently comes from milium, the seed of millet, which the little shell resembles.* It would have been milliola other- wise, I suppose, for the inventor would hardly have chosen the obsolete mile for such a purpose.
Siva is a male deity, not a goddess.
Brachiopoda— spiral arms,” “which they can uncoil and protrude.”
Woodward says, “Jt has been conjectured, ete. . . this supposition is
rendered less probable by the fact that, in many genera, they are supported by —
a brittle skeleton of shell’—Manual, p. 211.—I am, dear sir, yours truly, Henry Entey.—We regard Mr. Eley’s communication as a most important note, and we cordially introduce it, as expressive of our sincere wish to add to the usefulness of Mr. Page’s valuable book, to remove some more of the numer- — ous stumbling blocks already laid in the student’s path by the bad Latinism of
very many of the modern naturalists and paleontologists. There is not only a
* Tf crowded aggregation is implied, the spike of millet is a most apt similitude.
NOTES AND QUBRIES. 37
want of a critical guide for the unlettered student, but the faulty pronuncia- tion in vogue seems little likely to be corrected without a good standard of reference more ready at hand than dictionary and gradus. We may remark that, besides those instances mentioned by Mr. Eley, several of which, especially affinis, gigantéus, céncavus, edilis, are sldom rightly spoken among geologists, there is the frequent mispronunciation of such words as the gene- tives of proper names; thus, Milleri wrongly for Milléri, Seduleri for Scouléri, and the like ; also Ganoidéa, Crinoidéa, Cystidéa, &c., are not always thus cor- rectly pronounced. We may, however, remind tyros that family names, such as Ostréide, are to be pronounced as Mr. Page thus marks, not Ostreide, as it is incorrectly and too commonly spoken.
In Mr. Page’s list at p. 40, multifidus has no accentuation, it should be mul- tifidus—too often pronounced multifidus wrongly ; so also quadrifidus and tri- fidus. Hemisphericus (p. 398) should be hemisphericus. Fossilis (p. 396) should be accentuated fossflis. Cervical at p. 111 should be Cervical, not Cérvical.
We here add some other corrections which have been pointed out to us b another correspondent, and we hope the book will be all the better for a criticisms in the next edition. For its sake we are open to receive more notes of corrections, so that both tyro and Mr. Page may have the benefit thereof. Digitalus, finger-like, should be either digitalis, belonging to a finger, or digitatus, fingered—formed as fingers; dorsalis should have its accent on the middle syllable ; gagateus may be accented thus, gagdteus. In the Latin, Konig should be spelt Koenigius; so also Noeggerathius. Longimanus wants the accent at p. 401. The correction of psilépora for the incorrect psilopdra (p. 409), and tubipora for tubipdéra, may remind many of the common wron pronuncation of the multitude of names of corals and bryozoa partly peared of pora,a pore. Pygmeus, unaccented at p. 409, should have its penultimate syllable long; this is often forgotten. In the same page, pucillus is apparently a misprint for pusillus, and Rankinei for Rankinéi. Saxatilis at p. 410 should be Saxatilis. ‘Toliapicus (p. 414) has, we believe, a reference to Tolapia, or some similar form of the Latin name of the Isle of Sheppy. Unicolor should take the place of the incorrect unicdélor. Méeandrinus should be placed for meandrinus, Macréstomus for macrostémus. Moniliformis and monilitectus monileformis, etc. Muensterianus for Mimsterianus (after Count Minster). Cypridina-Schiefer (p. 137) should not be half Latin half German, but as the Germans have it, Cypridinen-Schiefer.
We would suggest that the description of Brachiopoda at page 96, may be corrected thus :—“ which they cannot uncoil and protrude, but with which” ete.
SLICKENSIDES.—Dzar Sir,—I was much interested by the queries and re-
lies, upon the subject of slickensides, in the last number of the “‘ Geonoerst.”
hey are very abundant in the Keuper sandstone of Cheshire, and the south- west of Lancashire. Usually, two polished striated surfaces exist together, but not always, for occasionally a single slickenside is only opposed by a soft sandstone, without any trace of such an appearance. Those said to be two feet apart, I think can have no connection with each other. Faults are very numerous in this neighbourhood ; in width they vary from an inch to twenty yards. They are always filled with sandstone, very much harder than the strata bounding them, while at each side slickensides abound. If the strata at each side of the fault is removed, the enclosed compact rock stands across like a wall, beautifully polished and striated upon each side. In such cases it is evident that the polished surfaces could not have been caused by the original disruption of the strata, but afterwards—long after the fault had ‘been filled by debris. I am therefore of opinion that a throw of the strata to a very small extent, acting under immense pressure, was suflicient to cause the phenomena.
38 THE GEOLOGIST.
This is confirmed by the occurrence of slickensides at different angles in slides of the rock within the faults, and also by highly polished surfaces, occurring in ve slight faults, which displace the strata only a foot or eighteen inches.
believe it is the compact sandstone within the faults, and not the slicken- sides, that is considered to act as a barrier to subterranean water—I remain, dear sir, yours ete., GeorcE Hittosron, F.G.S., Liverpool.
SLICKENSIDES.—Dn4r Srr,—The subject of “slickensides” is one to which T have paid some attention, and I have always noted as many of the facts relating to this appearance on rock-surfaces as I possibly could. I have read with much interest in the last number of the “Gxroxocisr” the queries on “slickensides” submitted to the Geological Section of the British Association during the meeting at Aberdeen, by Mr. Price, and the replies by Professor Ansted. Permit me to offer a few remarks on this really curious and interest- ing subject.
The formation of a “slickenside” on any rock-surface is due to the sliding of one rock-mass on the other, the motion very possibly having been a slow one, but exerted under enormous pressure, and without the aid of more heat than would have been produced by the friction. The result of this motion would, in the first instance, be the pulverization more or less of the two opposing rock-surfaces, and when this crushing action ceased, the re-consolida- tion of that crushed material, by means of enormous pressure, accompanied by motion.
I find in limestones and sandstones that most usually the “ slickenside-” striz are on the surface of the beds, and their direction frequently parallel to that of the dip. In my geological notes I find many references like the following: “Slckensides-strie parallel to the dip of the beds, showing vertical displace- ment in the mass ;” but when the stria are transverse to the dip, and in the direction of the strike of the beds, I say that “horizontal displacement is indicated.” In either instance of course there is no faui¢t produced in the strata, though a displacement of them ez masse is clearly indicated, the direction of which being pointed out by that of the strie of compression. This is the only way in which rock-masses can be displaced without being faulted.
The slickenside-strie are frequently oblique to the dip of the beds, the angle of obliquity being of course variable, but always indicating the direction of the displacement.
The thickness of the slickenside, or striated substance, is very variable ; sometimes it is as thin as card-paper, at others nearly an inch from one surface to the other. It varies also im its internal structure: sometimes it consists throughout of a series of very thin and finely striated lamelle, which readily flake off from each other by the application of a penknife, or when struck on the fractured edges with the hammer. At other times this structure is only
artial, and confined to the surfaces; and again, when the slickenside is tolera-
ly thick, it is homogeneous throughout, the surfaces above presenting a highly-polished or glazed appearance, but not such as would be the result of vitrification.
In limestones the slickenside frequently appears as a white calcareous material resembling opaque carbonate of lime, but coated with a carbonaceous- looking glaze, which readily soils the fingers. In slate or sandstone-rocks the slickenside is most usually homogeneous in its structure; it comes away in small slabs, and resembles dull-looking quartz, or quartzite, having both sur- faces highly polished, beautifully and often deeply striated, and stained of a dark manganese—brown, or black colour.
The most remarkable kind of slickenside I know of is one not unfrequent in the carboniferous limestone of Ireland; it exhibits two distinct sets of strie,
NOTES AND QUERIES. 39
arranged more or less at right angles to cach other, and closely adhering, one set being parallel, or nearly so, to the dip, and the other to the strike of the beds.
From this it would appear that the beds above and below had two distinet motions given to them, but at different intervals of time. In the example be- fore us we have evidence for betoutae that at first one set of beds moved while the other remained stationary ; and that one half of the crushed intervening sub- stance, while adhering to the moving mass by cohesion was pulled into a state of striation to the amount of only one- half its thickness. The motion then suddenly ceased, and the adjoining beds were moved, but in a direction directly contrary to the first, The remaining
ortion of the pulverized material fol- owed this second impulse, and assumed a striated structure, the lines of which were parallel with the direction of the displacement and ee reaeently at an opposite angle with that which was first formed.
We have in Brockedon’s patent pen- - avg eee
. * j x o cils a familar i BE lie _cecon-|% ere cots fais aisles, 1 solidation of a powdered substance by the application of enormous pressure into a material harder and more free from grit, or other impurities, than the original native plumbago, and to this our slickensides bear a striking analogy. Dear rk faithfully yours, Geo. V. Du Noyrr, M.R.I.A., Geological Survey of Treland.
PusuisHeD Accounts oF Fosstr Human Remains.—Sir,—Will you oblige me by answering the following query in the “ Gnoxoeist.” I ask as well for others as myself. Where may be procured the fullest and most re- liable information respecting fossil human remains that have been discovered in the world? Susscriper, Redlands.—There is no connected account of the human remains discovered in various parts of the globe, and it is one of the objects of the papers on the “ First Traces of Man on the Globe.” now pub- lishing in this magazine, to give a collected account of all the reliable cases, and to give illustrations of the ancient flint-weapons, etc., as also of the stone-implements recently, or still in use amongst savage tribes in various parts of the world.
The best account of human remains published up to the present time will be found in the appendix to M. Boucher de Perthes’ book. Other notices may be profitably consulted, such as Dr. Mantell’s paper, read at the Oxford meeting of the Archeological Institute, 1850, and M. Marcelde Serres’ several papers in the Bulletin Soc. Geol. de France, Comptes Rendus, etc.
Deposition oF Warpr.—Srr,—In “ Notes and Queries,” in the ‘‘ GEoxo- cist’ for December last, W. Nottingham asks two questions, viz., 1st. Where does the warp come from? 2nd., Howis it that the Humber and its tributaries =the ae Ouse, Don, etc., are the only rivers in Great Britain that deposit
‘warp’
When we take into consideration the fact that the Humber receives the
40 THE GEOLOGIST.
drainage of nine thousand one hundred and seventy three square miles, of which the Trent alone draws from four thousand five hundred square miles, the re- maining four thousand six hundred and seventy-three square miles supplying the Ouse, we may form some idea where part of the “warp” comes from. What proportion river-sediment from floods, etc., may supply, I cannot pretend tosay. Then we have the gradual wearing away of our Yorkshire coasts from two miles east of Bridlington Quay to Spurnt Point, which is a distance of about forty-three miles. Along this coast we lose, on an average, six feet three inches annually. In fact new roads have continually to be made in con- sequence of the sea making such rapid encroachments on the land, which, when washed away, is taken up the Humber and constitutes another source from which the “warp” is formed, and deposited upon lands up the rivers, ete.
I think your correspondent, W. Nottingham, will be able to draw from these facts answers to both his questions. I believe that no other river, or rivers in England are situated under such favourable circumstances for making the deposits called “ warp” as are the rivers above mentioned.—Dear sir, yours faithfully, Epwarp Tirnpaxt.
REVIEW.
Mr. Tennant’s Mineraloyical and Geological Collections.
We have received specimen cases of the two hundred, and three hundred selected examples of fossils and minerals, accompanied by the very useful cata- logue of ordinary British fossils, recently published by Mr. Tennant. These collections are designed as an initiary means of instruction for students and tyros. Nothing so much tends to facilitate and encourage the study of any science as a ready means of access to the principal objects referred to in the general descriptions and writings of authors. It is easy to accumulate speci- mens of rocks and fossils, and to form expensive collections; but it is not so easy to form a limited and proper selection which shall at once illustrate the chief facts of a science, and be of real service to the student.
Professor Tennant’s well known intimate knowledge of minerals gives confi- dence to learners as to the correctness of the naming of the specimens, and his long experience in this class of rudimentary collections—first made by his im- mediate predecessor, Mr. Mawe, more than fifty years ago—shows itself in the completeness and perfection of the present cabmet collections, in which, al- though the samples of fossils and minerals are of small size they are typically characteristic, and have every scientific advantage of displaying sufliciently their characters with that essential one of condensed space. ‘The cabinets in which the collections are contained are strongly and neatly made, and, whether as useful and interesting presents at this season of gifts, or viewed in their proper light of aids to the comprehension of elementary treatises on ee or Mineralogy, they are well worthy of the recommendations given to them by Sir Charles Lyell, the late Dr. Mantell, and other eminent geologists, and in which we readily concur.
THE GEOLOGIST.
FEBRUARY, 1860.
GEOLOGICAL LOCALITIES.—NO. I. FOLKESTONE. By S. J. Macxris, F.G.S., F.S.A.
Time passes away, and we all of us grow older and older. As day by day the daylight lengthens or contracts, the air gets warmer or chillier, the skies brighter or bleaker, and everything around us imperceptably changes, it is only after the lapse of weeks that we perceive the change.
Lign. 1.—Eastwear Bay, from Copt Point.
_ Yet Time never stays his rapid course ; and in mid-life it is per_
haps for the first time we stop in our onward path to feel, for the
first time too, we are not what we were. VoL. m.
42 THE GEOLOGIST.
Years ago, when a child, I picked up shells and pebbles on the Kentish strands. In school-boy days, with bolder hand and surer foot, oft have I scrambled o’er those white chalk-cliffs, or clambered homewards for six long miles o’er sea-weeded rocks with satchel loaded full of fossils gathered from the slippery shores of Hastwear Bay, were the dark-blue crumbling Gault daily yields its crop of glittering fossils to the destructive battering of the salt sea waves.
As the home almost of my childhood do I still look back to Kast- wear Bay. On its flat and sanded shores are dotted innumerable earth coils of ever-working worms, o’er the bronzed and unctuous fields of tangle and fucoids, and the barnacle-crusted rocks are spattered myriads of tiny tube-worms (Spirorbes and Serpule), and thousands of patches of the matted and netted towns of bryozoans (Eschare and Flustre). The rough waves wash up the almost senseless bristled sea-mouse (Aphrodita aculeata). Perriwinkles cling to the overlapping algals, and troups of limpets at the recess — of the tide march down with solemn step and slow to browse in the fields of the serrated fuci, retiring before its flood to fit themselves fastidiously down again to their perches on the rocks. Lobsters and crabs pass seemingly happy days in holes amongst the bigger stones, while eolids, dorids, and other inhabitants of the deep wade here ashore o’er smooth, or rugged paths to spawn.
The long line of undercliff, the Warren, stretches in romantic ~ beauty its chains of hill and dale along beneath the tall white cliffs, that proudly lift their lordly crests five hundred feet above the sing- | ing waves below.
Who is there amongst us with heart so dead as not to admire and delight in such a scene as this? Who, from the fairest of England’s ~ daughters to the sunburnt labourer, is dead to those charms of sense. and scene which ever-varied Nature ever variedly presents to refresh — the heart of the poor mechanic as thoroughly and as truly, as they do the gentler and more exquisite sensibilities of those who have never known a care.
“Come with me,” says Lewes, in one of his beautiful ‘ Studies,
‘come with me and lovingly study Nature, as she breathes, palpitates, and works under myriad forms of Life.” Come with me,
THE GAULT. 43
GEOLOGY OF FOLKESTONE
too, and lovingly study Nature; only come with me with a stouter heart and bolder step, and let us venture one essay into the myste- rious past.
Where shall we begin? “ Anywhere,” says Lewes, “will do.” And truly so it will, for the geologist as well as for the naturalist.
Lign, 2.—The Warren, with Nastwear Bay and Copt Point, from the summit of Abbot’s Clift.
We are already in the Warren. I remember it before it was spoilt by that great ugly gash of a railway-cutting, through which the fiery locomotive whizzes like a smoking rocket furiously along. I re- member it in its solemn quietness; and oft, as the sammer’s glorious sun was placidly sinking in the west, have I wandered o’er its grassy mounds, or along its bordering sands beneath, where
“The prawn-catcher wades through the shore-rippling waves.”
Beautiful indeed is that white land-locked bay in its fairy like purity. Serenity itself is that solemn glassed expanse of level water. How sweetly, too, the dying glories of the ruddy sun tip the highest peaks of chalky cliffs, while all below is shrouded up in solemn shadow, save off at sea, where
“ Bright gleam the white sails in the stout rays of even, And stud as with silver the broad level main ; While glowing clouds float on the fair face of heaven, And the mirror-like water reflects them again.”
44, HE GEOLOGIST.
Ever since I knew it has the Warren been just like this—almost unruffled in its solemn and stately aspect even by the stormy sea. Land, water, sky, all too broadly grand to be speckled by the pigmy waves, whose sullen sounds the mighty cliffs but backward throws “ faultering into whispers low.” Here then let us begin.
There are older men than I that know the Warren well, and little is the change in it that they have seen. Like me they have grown from childhood into man; and more than I, they have passed into childhood—dreary, sad, exhausting childhood, not fresh and young— again ; and yet little is the change that they have seen. ‘There were those tall white cliffs when they were boys; there was that “wreck of ages” spread below ; there was that broad mass of cliffs, and that wide solemn glass of sea that daily showed their pure white forms ; there was that blue and slippery shore, those yellow sands, that rocky tract. Mounds of fallen chalk were piled against the cliffs be- yond, while only a casual block tarnished the verdant carpet of the Warren.
Long years have flitted by since man recorded any change in this serene and solemn scenery. Already the recording lines on the tombstone’s “frail and crumbling frame”—the dead man’s chronicle —touched by time are half effaced. And then how slight the change recorded. Well may we look up at those old cliffs and think how old they are.
But need I say that once, in time’s long sequence of changes strange, those cliffs were Ocean’s mud—deep sea-bed ooze. How long ago is that? Older than the days when perhaps the brazen arms of conquering Romans clattered on this slippery strand; older than the days of Phoenician traffic with our island’s mines for tin; older than the aboriginal Briton, or the hairy mammoths that in- habited this very land, ere Adam was, or human race began; older than that great and three-fold age (the Tertiary) when living species first appeared; older than ten thousand times ten thousand ages is the rock-mass of those fair and stately cliffs; and older still, older still by ages, is that dark blue clay that forms that slippery shore. And this blue clay it is that has made Folkestone one of the chief towns in the geological territory. Few geological localities have’ been longer or more justly celebrated in the annals of geology than”
MORLOT—SOME GENERAL VIEWS ON ARCHAOLOGY. 45
Folkestone has been for the beautiful iridescent fossils of the Gault ; for by that provincial (Cambridgeshire) name is this blue stratum known to geologists. Not that these fossils are large or massive ; not that they are parts and portions of the former monsters of the earth or sea; not that they have any economic value, or are capable of any commercial use. Probably they were not even the finest of their race while sporting yet with vital energy in their ancient sea ; for only little shell-fish, or cuttle-fish were they—small, delicate, and pearly. . (To be continued.)
SOME GENERAL VIEWS ON ARCHAIOLOGY.*
By A. MORLOT, OF LAUSANNE, SWITZERLAND.
A century has scarcely elapsed since the time when it would have been thought impossible to reconstruct the history of our globe prior to the appearance of mankind; but though contemporary his- torians were wanting during this immense pre-human era, this era has not failed to leave us a well-arranged series of most significant vestiges. The animal and vegetable tribes which have successively appeared and disappeared have left their fossil remains in the suc- cessively deposited strata. Thus has been composed, gradually and slowly, a history of creation written as it were by the Creator him- self. It is a great book, the leaves of which are the stratified rocks following each other in the strictest chronological order, the chapters being the mountain-chains. This great book has long been closed to man; but science, constantly extending its realm and improving its method of induction, has taught the geologist to study those marvel- lous archives of creation, and we behold him now unfolding the past ages of our world with a variety of details and a certainty of conclu- sions well calculated to inspire us with grateful admiration.
* This article is the introduction to a paper entitled “‘ Geologico-Archxological Studies in Denmark and Switzerland,” appearing in the “ Bulletin de la Societé
Vaudoise des Sciences Naturelles” for 1859, and of which a separate edition, comprising the present pages, will be published.
46 THE GEOLOGIST.
The development of Archwology has been very similar to that of Geology. Not long ago we should have smiled at the idea of re- constructing the bygone days of our’ race previous to the beginning of history properly so called. The void was partly filled up by re- presenting that ante-historical antiquity as having been only of short duration, and partly by exaggerating the value and the age of those vague and confused notions which constitute tradition.
It seems to be with mankind at large as with single individuals. The recollections of our earliest childhood have entirely faded away up to some particular event which had struck us more forcibly, and which alone has left a lasting image amidst the surrounding darkness. Thus, excepting the idea of a deluge which exists among so many nations, and therefore appears to have originated before the emigra- tion of those same nations, the infancy of mankind, at least in Europe, has passed without leaving any reminiscences ; and history fails here entirely, for what is history but the memory of mankind.
But before the beginning of history there were life and indus- try, of which various monuments still exist; while others le buried in the soil, much as we find the organic remains of former creations entombed in the strata composing the crust of the globe. The anti- quities enact here a similar part to that of the fossils; and if Cuvier calls the geologist an antiquarian of a new order, we can reverse that remarkable saying, and consider the antiquarian as a geologist, applying his method to reconstruct the first ages of mankind pre- vious to all recollection, and to work out what may be termed pre- historical history. This is Archeology pure and proper. But Archeology cannot be considered as coming to a full stop with the first beginning of history, for the further we go back in our historical researches the more incomplete they become, leaving gaps which the study of material remains helps to fill up. Archeology, therefore, pursues its course in a parallel line with that of history, and hence- forth the two sciences mutually enlighten each other. But with the — progress of history the part taken by Archeology goes on decreasing, until the invention of printing almost brings to a close the researches of the antiquarian.
To pursue geological investigations, we must first examine the present state of our planet, and observe its changes—that is, we must
MORLOT—SOME GENERAL VIEWS ON ARCHAOLOGY. 47
begin by physical geology. This supplies us with a thread of induc- tion to guide us safely in our rambles through the past ages of our earth, as Lyell has so admirably set forth; for the laws which govern organic creation and the inorganic world are as invariable as the results of their combinations and permutations are infinitely varied, science revealing to us everywhere the perfect stability of causes with the diversity of forms,
So, to understand the past ages of our species, we must first begin by examining its present state, following man wherever he has crossed the waters and set his foot upon dry land. The different nations which at present inhabit our earth must be studied with re- spect to their industry, their habits, and their general mode of life. We thus make ourselves acquainted with the different degrees of civilization, ranging from the highest summit of modern development to the most abject state, hardly surpassing that of the brute. By that means Ethnology supplies us with what may be called a contempo- raneous scale of development, the stages of which are more or less fixed and invariable ; whilst Archeology traces a scale of successive development, with one moveable stage passing gradually along the whole line.*
Ethnography is, consequently, to Archeology what physical geo- graphy is to geology, namely, a thread of induction in the labyrinth of the past, and a starting point in those comparative researches of which the end is the knowledge of mankind, and its development through successive generations.
In following out the principles above laid down, the Scandinavian savants have succeeded in unravelling the leading features in the pro- gress of pre-historical EKuropean civilization, and in distinguishing three principal eras, which they have called the Stone-age, the Bronze-age, and the Iron-age.f
This great conquest in the realm of science is due chiefly to the labours of Mr. Thomsen, director of the Ethnological and Archezolo-
* Some naturalists see a correspondence of the same sort between embryology and comparative anatomy, for they consider the human embryo as passing during its development through the different stages of the scale of animal creation, or, at least, as passing through the different states of the embryos of the different Stages of that scale.
+ The history of Danish Archeology has been sketched by T. Hindenberg. See “Dansk Maanedskrift,” I. 1859.
48 THE GEOLOGIST.
gical Museums at Copenhagen,* and to those of Mr, Nielssen, profes- sor at the flourishing University of Lund, in Sweden.t These illus- trious veterans of the school of northern antiquarians have ascer- tained that Europe, at present so civilized, was at first inhabited by tribes to whom the use of metal was totally unknown, and whose in- dustry and domestic habits must have borne a considerable analogy to what we now see practised among certain savages. Bone, horn, and chiefly flint, were then used, instead of metal, for manufacturing cutting-instruments and arms. This was the Stone-age, which might also be called the first great phase of civilization.
The earliest settlers in Europe apparently brought with them the art of producing fire. By striking iron-pyrites (sulphuret of iron) against quartz, fire can be easily obtained. But this method can only have been occasionally used, and seems to have been con- fined to some native tribes in Terra del Fuego.{ The usual mode has been evidently that of rubbing two sticks together; but, on further reflection, it is easy to perceive that this was a most difficult dis- covery, and must at all events have been preceded by a knowledge of the use of fire as derived from the effects of lightning or from vol- canic action.
The Stone-age was, therefore, probably preceded by a period per- haps of some length, during which man was unacquainted with the art of producing fire. This, according to Mr. Flourens, indicates that the cradle of mankind was situated in a warm climate.§
The art of producing fire has been perhaps the greatest achieve- ment of human intelligence. The use of fire lies at the root of almost every species of industry; it enables the savage to fell trees,
* “TLedetraad til Nordisk Oldkyndighed.”” Copenhagen, 1836. Published in English by Lord Ellesmere under the title of “A Guide to Northern Antiquities,” London, 1848.
+ Nielsson. ‘“ Scandinaviska Nordens Urinvonare.” Lund, 1838-1843. | { Weddell, “ A Voyage towards the South Pole in 1822-1824.” London, 1827. PG /-
§ Flouren’s “ De la Longevité Humaine.” Paris, 1855. P.127. Man, from the construction of his teeth, his stomach, and hisintestines, is primitively frugivorous, like the monkey. But the frugivorous diet is the most unfavourable, because it constrains its followers perpetually to abide in those countries which produce fruit at all seasons, consequently in warm climates. But, once the art of cook- ing introduced, and applied both to animal and vegetable productions, man could extend and vary the nature of his diet. Man has consequently two diets: the
first is primitive, natural, and instinctive, and by it he is frugivorous; the second — is artificial, being due entirely to his intelligence, and by this he is omnivorous.
MORLOT—SOME GENERAL VIEWS ON ARCHMOLOGY. 49
as it allows civilized nations to work metals. The importance is so great, that deprived of it man would perhaps scarcely have risen above the condition of the brute. The ancients already were sensible of this. Witness the fable of “ Prometheus.” As to their sacred perpetual fire, its origin seems to lie in the difficulty of procuring it, thereby rendering its preservation essential.
In Europe the Stone-age came to an end by the introduction of bronze. This metal is an alloy of about nine parts of copper and one part of tin.* It melts and moulds well; the molten mass, in cool- ing, slowly acquires a tolerable degree of hardness—inferior to that of steel it is true, but superior to that of very pureiron. We there- fore understand how bronze would long be used for manufacturing cutting-instruments, weapons, and numerous personal ornaments. The northern antiquarians have very properly called this second great phase in the development of European civilization the Bronze-age.
The bronze articles of this period, with a few trifling exceptions, have not been produced by hammering, but have been cast, often with a considerable degree of skill. Even the sword-blades were cast, and the hammer (of stone) was only used to impart a greater degree of hardness to the edge of the weapon.
The Bronze-age has, therefore, witnessed a mining industry which was completely wanting during the Stone-age. Now the art of mining is so essential to civilization, that without it the world would perhaps yet be exclusively inhabited by savages. It is, therefore, worth our while to inquire more closely into the origin of bronze.
Copper was not very difficult to obtain. In the first place, virgin copper is not exceedingly scarce. Then the different kinds of ore which contain copper, combined with other elements, are either highly coloured, or present a marked metallic appearance, and are consequently easily known; they are besides not hard to smelt, so | as to separate the metal. Finally, copper-ore is not at all scarce, it is met with in the older geological series of most countries.
Virgin tin is unknown, but tin-ore is heavy, of dark colour, and
* Bronze is still used for casting bells, cannon, and certain parts of machinery. _ It must not be confounded with common brass, which is a compound of copper ' and zinc, much less hard, and appearing only in the Iron-age. VoL. 11. G
50 THE GEOLOGIST,
very easy to smelt. However frequent copper may be, tin is of rare occurrence. Thus the only mines in Europe which produce tin at the present day are those of Cornwall, in England, and of the Erzge- birge and Fichtelgebirge, in Germany.
But the question arises whether previous to the discovery of bronze, man, owing to the great rarity of tin, may not have begun by using copper in a pure state. If so, there would have been a copper-age between the stone- and bronze-ages.
In America this has really been the case. When they were dis- covered by the Spaniards, both the two centres of civilization, Mexico and Peru, had bronze composed of copper and tin, which was used for manufacturing arms and cutting-instruments, in the absence of iron and steel, which were unknown in the New World; but the admirable researches of Messrs. Squier and Davis on the antiqui- ties of the Mississippi valley* have brought to light an ancient civi- lization of a remarkable nature, and distinguished by the use of raw virgin copper, worked in a cold state by hammering without the aid of fire. The reason of its being so worked lies in the nature of pure copper, which, when melted, flows sluggishly, and is not very fit for casting. A peculiar characteristic of the metal, that of occasionally containing crystals of virgin silver, betrays its origin, and shows that it was brought from the neighbourhood of Lake Superior. This — region is still rich in metallic copper, of which single blocks attaining a weight of fifty tons have lately been discovered. There was even found at the bottom of an old mine a great mass of copper, which the ancients had evidently been unable to raise, and which they had abandoned, after having cut off the projecting parts with stone hatchets.+
The date of this American age is unknown: all we know is that it must reach as far back as ten centuries at least, that space of time being deemed necessary for the growth of the virgin forests, now flourishing upon the remains of that antique civilization of which the modern Indians have not even retained a tradition.
* Squier and Davis.—* Ancient Monuments of the Mississippi Valley.” Smithsonian Contributions to Knowledge. Washington, 1848. It is one of the most splendid archzeological works ever published.
+ Lapham.—“ The Antiquities of Wisconsin.” Smithsonian Contributions to Knowledge, p. 76, 1855.
MORLOT—SOME GENERAL VIEWS ON ARCHMOLOGY. 51
It is finally worthy of remark that the “mound-builders,” as the Americans call the race of the copper-age, seem to have preceded and prepared the Mexican civilization, destroyed by the Spaniards ; for in progressing southwards, a gradual transition is noticed from the ancient earth-works of the Mississippi valley to the more modern constructions of Mexico, as found by Cortez.
In Europe the remains of a copper-age are wanting. Here and there a solitary hatchet of pure copper is found; but this can easily be accounted for by the greater frequency of copper, while tin had usually to be brought from a greater distance, so that its supply was more precarious.
Europe did not witness the regular development of a copper-age. It seems, according to M. Troyon’s very just remark, that the art of manufacturing bronze was brought from another quarter of the world, where it had been previously invented. It was most probable some region in Asia, producing both copper and tin, where these two metals were first brought into artificial combination, and where also traces of a still earlier copper-age are likely to be found.
An apparently serious objection might be started here, by raising the question how mines could be worked without the aid of steel. This, however, is sufficiently explained by the fact that the hardest rocks can be easily managed by the agency of fire. By lighting a large fire against a rock, the latter is rent and fissured, so as to facili- tate considerably its quarrying. This method was frequently employed when wood was cheaper, and is even practised in the pre- sent day in the mines of the Rammelsberg, in Germany, where it facilitates the working of a rock of extreme hardness.
That metal of dingy and sorry appearance, but more precious than gold or the diamond—iron—at length appears, giving a wonderful impulse to the progressive march of mankind, and characterizing the third great phase in the development of European civilization, very properly called the Iron-age.
Our planet never produces iron in its metallic or virgin state, for the simple reason that it is too liable to oxydation. But among the aérolites there are some composed of pure iron, with a little nickel, which alters neither the appearance, nor the qualities of the metal. Thus the celebrated meteoric stone met with by Pallas in Siberia was
52 THE GHOLOGIST.
found by the neighbouring blacksmiths to be malleable in a cold state.* Meteoric iron has even been worked by tribes to whom the use of common iron was unknown. Thus Amerigo Vespucci speaks of savages near the mouth of the La Plata, who had manufactured arrow-heads with iron derived from an aérolite.t Such cases are certainly of rare occurrence, but they are not without their import- ance, for they explain how man may probably have first become acquainted with iron, and they also account for the occasional traces of iron in tombs of the Stone-age, if, indeed, this fact be well established.
It is, notwithstanding, evident that the regular working of terres- trial iron-ore must have been a necessary condition of the commence- ment and progress of the Iron-age.
Now iron-ore is generally found in most countries, but it has usually the look of common stone, being distinguished neither by its weight, nor colour. Moreover, its smelting requires a much greater degree of heat than copper or tin, and this renders its production considerably more difficult than that of bronze.
But even when iron had been obtained, what groping in the dark, and how much laboriously accumulated experience did it not require, to bring forth at will bar-iron or steel! Chance, if chance there be, may have played a part in it; but as chance only favours those privi- leged mortals who combine a keen spirit of observation with serious meditation and with practical sense, the discovery was not less diffi- cult nor less meritorious. We need not, then, be surprised if man arrived but tardily at the manufacture of iron and steel, which is still daily bemg improved,
In Carinthia traces of a most primitive method of producing iron have been noticed. The process seems to have been as follows :— On the declivity of a hill was dug an excavation, in which was lighted a large fire. When this began to subside, fragments of very pure ore (hydroxyde) were thrown into it, and covered by a new heap of wood. When all the fuel had been consumed, small lumps of iron would then be found among the ashes.{ All blowing appa-
* Pallas.— Voyages en Russie,” Paris, 1793, vol. iv., p. 595. There was but one mass of meteoric iron; it weighed 1,600 lbs.
+ “ Smithsonian Contributions to Knowledge,” vol. ii., art. 8, p. 178. { Communicated to the author by mining-engineers in Carinthia.
MORLOT—SOME GENERAL VIEWS ON ARCHMOLOGY. 53
ratus was in this manner dispensed with—an important fact when we come to consider how much its use complicates the metallurgical operations, because it implies the application of mechanics. Thus, certain tribes in Southern Africa, although manufacturing iron and working it tolerably well, have not achieved the construction of our common kitchen-bellows, apparently so simple: they blow laboriously through a tube, or by means of a bladder affixed to it.
The Romans produced iron by the so-called Catalonian process, and the remains of Roman works of that description have been discovered and investigated in Upper Carniola, Austria.* The Catalonian forge is still used in the Pyrenees, where it yields tolerable results ; but it consumes a large quantity of charcoal, requires much wind, and is only to be applied to pure ore containing but a very small pro- portion of earthy matter, producing scoriz. The process, in fact, con- sists in a mere reduction, with a soldering and welding together of the reduced particles, without the metal properly melting. Accord- ing to the manner in which the operation is conducted, bar-iron or steel are obtained at will. This direct method dispenses with the inter- mediate production of cast-iron, which was unknown to the ancients, and which is now the means of producing iron on a great scale.
Silver accompanied the introduction of iron into Europe—at least, in the northern parts; whilst gold was already known during the bronze-age. This is natural, for gold is generally found as a pure metal, while silver has usually to be extracted from different kinds of ore, by more or less complicated metallurgical operations—for example, cupellation.
With iron appeared also, for the first time in Europe, glass, coined money—that powerful agent of commerce,—and finally the alphabet, which, as the money of intelligence, vastly increases the activity and circulation of thought,t and is sufficient of itself to characterize a new and wonderful era of progress. From thence we can date the dawn of history and of science, in particular of astronomy.
* Jahrbuch der K. K. Geologischen Reichsanstalt. 'Vienna, 1850, vol. ii., p. 199. Carinthia and Upper Carniolia formed part of the Roman province Noricum, celebrated for its iron.
+ “The circulation of ideas is for the mind what the circulation of specie is for commerce—a true source of wealth.’ C.V.de Bonstetten. ‘ L’homme du midi et ’homme du Nord.” Geneva, 1826, p. 175.
54 THE GEOLOGIST,
The fine arts also reveal, with the introduction of iron in Europe, anew and important element indicating a striking advance already in the stone-age, but more so in the bronze-age; the natural taste for art reveals itself in the ornaments bestowed upon pottery and metallic objects. These ornaments consist of dots, cireles, and zig- zag, spiral, and S-shaped lines, the style bearing a geometrical cha- racter, but showing pure taste and real beauty of its kind, although devoid of all delineations of animated objects, either in the shape of plants or animals. It is only with the Iron-age that art, taking a higher range, rose to the representation of plants, animals, and even of the human frame. No wonder, then, if idols of the Bronze-age as well as of the Stone-age are wanting in Europe. It is to be pre- sumed that the worship of fire, of the sun, and of the moon, was prevalent in remote antiquity—at least during the Bronze-age, per- haps also during the Stone-age.
The preceeding pages constitute a sketch, certainly very rough and imperfect, of the developments of civilization. They establish, how- ever, in a very striking manner the fact of a progress, slow, but uninterrupted and immense, when the starting point is considered. The physical constitution of man has naturally benefitted byit. The details contained in the treatise of which the present paper forms the introduction prove that the human race has been gradually gaining in vigour and strength since the remotest antiquity.* The domestic races also—the dog first, then the horse, the ox, and the sheep have shared in this physical development. Even the vegetable soil has been gradually improving since the Stone-age—at least in Denmark. And yet there are persons who deny all general progress, seeing everywhere nothing but decay and ruin, like that worthy specimen of a Northern pessimist, who exclaimed—‘ See how man has degenerated ; he has even lost his likeness to the monkey !”
* This agrees perfectly with the testimony of statistics. See “ Quetelet sur Vhomme et le developement de ses facultés.” Paris, 1835, vol. ii., p. 271. This work of first-rate merit is very near akin to archeology. M. Quetelet has just published a new work, which will certainly be even more remarkable than the first, and which the author of the present paper regrets not to have had within his reach.
ROBERTS—UPPER SILURIAN CORALS. 55
UPPER SILURIAN CORALS.
A SKETCH BY GEORGE C. ROBERTS.
CoraL-HUNTING in the debris of a Wenlock-shale quarry ranks high— to my thinking—amongst the pleasures of geology. And, indeed, has no insignificant place among its wonders. For to any one not conversant with zoophytic life, it is hard to believe that the rugged corals that lie strewn about the quarry, once held sensitive masses of life—that from every pore tiny arms waved to and fro in the water to entangle the lesser creatures they lived on ; and that the animal— that slight thread of jelly-like substance, filling each tube, was at once a limb of the body and an independent creature, contributing, while attached, to the general support, and being able, if severed from the mass, to lead a separate existence and be itself the parent of others. The Wenlock series of the Upper Silurians have been rightly regarded as the metropolis of its zoophytic life, for both in variety and number, corals culminated in the seas of that age. Of these species, “so far removed from existing ones as to be quite unknown in modern seas, all, with rare exceptions, dying out at the close of the Paleozoic epoch.”’* I will essay a familiar sketch.
T adopt the nomenclature of M. Milne Edwards, whose valuable memoir of Silurian corals, published by the Palzontographical So- ciety, is my guide and instructor.
True corals are called by zoologists Zoantharia; and those with which we have now specially to do belong to the order Anthozoa. They have again been divided into cup-, and star-corals—Zoantharia rugosa, and millepores—Z. tabulata. The first division may either be simple—tenanted by a single polyp, or compound—the result of an aggregation of polyps, the latter, as its name implies, must always be the shelter and defence for a community. The animal itself was a
* “Siluria,” 3rd edition.
56 THE GEOLOGIST.
simple gelatinous substance, having power of expansion according to its wants, and being able to secrete lime from the ocean, and perhaps to transmute chemically other salts into lime, with which it built around itself a stony skeleton, a home to live in, and a defence from injury. In accordance with the thread-like growth of the polyp, we shall find these stony houses built up in most cases of tubes, through which the animal extended itself, the open end or summit forming its communi- cation with the outer world.
These tubes are in most species crowned with a certain number of ridges, disposed like the rays of a star; these took their shape from the slender fishing arms of the polyp, and formed their protection. The summit of the tube is called the calice, or cup, and the ridges that radiate from its centre are known as septa. The beautiful pat- tern that covers the surface of a coral is owing to the preservation of these star-like septa, and by the variation in their forms and number combined with altered shape of the calice we distinguish species. For in this tiny cup are printed more definitely than elsewhere the characteristics of its inhabitant.
Tt is well to examine every piece of milleporal coral in three several ways. First, look at its upper surface and note the form and con- — struction of its calices and the number, if any, of their septa; then, turning it sideways, observe whether the tubes of which these calices — are the termination are continued to the base of the coral, or die away in its substance, and lastly, look at the under-surface, notice if the basal plate is free avid unattached, or is furnished with a pe- duncle, or foot of attachment. But in describing the species, it is best to begin with the cup-corals. The normal form of this first great division of zoophytic life is that of a simple cup, produced by a — polyp which expends all its strength in the development of a single calice. In some species, however, such solitary polyps are aggregated together, sometimes accidentally so, as in Cyathophyllum articulatum, usually found in groups of strongly-walled corallites, growing up to- gether without interfering with each other; and.in several species of cup-coral a peculiar method of reproduction—no less than “ the life of the parent being continued in that of the offspring,” by buds grow- ing out of the centre of its calice, gives a composite character to what was before a solitary polyp. For the buds growing up and expand-
ROBERTS—UPPER SILURIAN CORALS. 57
ing, crowd upon each other’s limits, and a mass of corallites is the re- sult, whose base is the old parent coral, and whose upper surface is covered by the star-rayed cups of the children. Acervularia ananas is the commonest species of these family corals.
The polyps that formed these cup-corals grew from their base up- wards, and were probably long livers, for a well-matured specimen of Cyathophyllwm Loveni will measure five inches in height, indicating by the number of prominent edges that surround it—accretion- wrinkles they are called—a long and chequered existence ; for when these are regularly prominent, we infer the polyp led an active life of development. On the contrary, when their irregularity forms annu- lar depressions on the corallum, these indicate the occasional repose of the zoophyte from its work of extension.
The common species belonging to these cup-corals are easily known. Oyathophyllum Lovent has very prominent accretion- wrinkles, while upon the sides of CO. angustum they are but feebly developed. O. pseudoceratites has an oval calice, with only thirty- eight large septa alternating with a like number of smaller ones ; the two former species have sixty of each kind. Omphyma turbinata isa short, wide-mouthed species, with double the number of septa, and has radiciform appendages, 7.e., rootlets, attached to its lower end. O. subturbinata differs only in being taller, as its name implies, having but eighty septa, and well developed accretion-wrinkles. 0. Murchisoni is nearly allied, but has vesicles, or bladder-like tubercles, coming up among the septa. Then there is Goniophyllum Fletcheri with a square calice; Aulacophyllum mitratum, a small turbi- nated cup, whose principal and rudimentary septa combined only amount to sixty-eight, and Ptychophyllum patellatum, with one hun- dred septa, and the border of its calice so much raised that the coral- lum resembles the cap of a mushroom. These are all the simple cup- corals we are likely to meet with in the Wenlock rocks. Among the composite ones is the species I before alluded to, Cyathophyllum arti- culatum, generally met with as a mass of tall slender corallites, so thin-skinned that their upright internal lines of structure (cost«) are clearly visible. Syringophyllum organum is another, having star- headed tubes of exquisite beauty ; and as a connecting link between this and the next division of cup-corals, we have Acervularia luau- i YOu. 11. H
58 THE GEOLOGIST.
vians, which resembles the preceding in the development of the inner walls of its corallites, but differs from them, and allies itself to the next by its mode of reproduction, which is exclusively calicinal. This gemmation, as it is called, is a very interesting and instructive feature. Cyathophyllum truncatum is a good example of it. I have ~ often picked up this coral in a Dudley, or Wenlock lime-quarry, in which the parent—a simple, but somewhat angular shaped cup—has been smothered by the growth of young buds from out its calice. Indeed, in many specimens I have seen, these un- natural children have in turn borne young, and a tall turbinate mass of corallites, with calices mis-shapen by crowding together, has grown up.
The last division of the “ cup- and star-corals” includes those com— posite species that have a common basal plate, and grow by accre- tional development. Strombodes typus is the best known. The star-headed terminations of its corallites cover the surface with ir- regular polygonal figures, the value of whose angles would puzzle old Euclid himself. This species has vertical internal radii, thus differing from its ally, S. Murchisoni, whose inner structure is completely vesi- cular. Another species, S. Phillipsii, has elegantly shaped ealices, having their angles gracefully lengthened; while the perfection of beauty is attained by S. diffluens, whose surface, exhibiting no trace of walls dividing the corallites, is covered with the most exquisite septal floriations.
Nearly allied by form of calice to the cup-corals are the Fungide, or “mushroom-corals,” an outstanding group of which one genus only seems to have lived in Silurian seas, Palewocyclus it is called, «e., ancient circle. P. porpita has a quoit-like corallum, thirty large septa alternating with a like number of smaller ones, and a curved pedunele-foot of attachment. P, preacutus is about the size, and not much thicker than a sixpence, has forty-eight uniform septa, and no peduncle. P. Fletcheri is about half an inch high, has a strongly curved peduncle, and well marked accretion-wrinkles ; superior height gives it advantages, you see. But P. rugosus is taller still, somewhat top-shaped, and has a small peduncle, oddly turned up.
I have now to describe the milleporal corals, the second great
ROBERTS—UPPER SILURIAN CORALS. 59
division of Silurian Zoantharia, differing widely from the cup- and star-corals, both in shape and character. They are all composite—no single tube or cup could be a millepore, either in fact or by courtesy, for the name implies the aggregation of a number of polyps having more direct connection with each other than the cup-corals. In shape they are both massive and branching. The first two genera, Heliolites and Favosites, are distinguished from each other by the ab- sence of those septa in the latter that form such elegant star-like dises as they fill up the calices of the former.
Heliolites, i.e., sun-coral, is so named from the sun-like appearance of its calices. H. interstincta has these calices closely set, and equal in distance from each other, the intervening space, called the caenenchy- ma, being filled with polygonal cells. Upon the surface of H. Mur- elusoni the calices are not closely set, and vary in approximation. H. megastoma is easily known from either ; large, closely set, calices cover its surface, and what coonenchyma their nearness permits is made up of square cells. All these are massive corals irregularly hemispheri- cal in form, and having a basal-plate strongly marked with concentric ridges. The branching Heliolites are still more elegant. H. Grayii is rudely branched, and bears its sun-like calices on both surfaces. The only known specimen of this species was found in the Wenlock shale of Walsall, and is in the cabinet of its discoverer, Mr. Gray, of Hagley. H. imordinata is decidedly arborescent in form, very slenderly branched, and bearing calices, whose rarity is made out by the extreme beauty of their form. This, however, is peculiar to Lower Silurian rocks, and I only introduce it here to complete my sketch of Heliolitic corals.
The genera Plasmopora and Propora differ from Heliolites, mainly in the appearance of their surfaces, the septal rays being prolonged beyond the edge of the calice, and united to other rays which cover the coonenchyma. In every species of these three genera the number of septa contained in each calice is twelve.
Next come the Favosites. These have no intervening coonenchyma, the coral being simply a bundle of tubes. The radiating septa of their calices are only developed in one species, and that a rare one, FP. Hisingeri. F'. Gothlandica is the typical form; this has strongly walled tubes, which, coming up to the surface, cover it with a cali-
60 THE GEOLOGIS®.
cinal pattern of five-sided divisions, unequal in size. This differs mainly from F’. aspera, in having its surface convex instead of flat. A broken piece of I’. aspera, however, will show the edges of the tubes toothed, instead of smoothly columnar as in I’. Gothlandica. F. multipora has its calices equal in size, and very regular. These three species are the giants of their tribe, specimens weighing sixty or eighty pounds are not uncommon in the Wenlock shale of Dudley, or Benthall Edge. A little below the Wych-pass at Great Malvern, where the Wenlock-shale rests against the west flank of the hill, a reef of Favosites crosses the footway, and may be traced in an un- broken line for some yards,
The calices of F’, Forbesti are very unequal in size, and quite circu- lar ; this, though a massive species, never attains the size of its allies. A side view of I’. fibrosa gives one the idea of a bundle of slender needles ; consequently its calices are scarcely discernible without a lens. FF. cristata is the only true branching Favosite; it may be known from other arborescent corals by the irregularity of form pre- sented by its calices.
Alwveolites is the genus most allied to the one I have been describ- ing. It differs in this important and easily recognized particular ; the calices of Favosites come up to the surface free and independent of each other, whereas in Alveolites each appears to overlap and in- trude upon its neighbour, though not so in reality. The largest massive species, A. Labecheti is perhaps the most elegant in its calici- nal pattern. A. Grayit is much like it, but has a flat instead of convex top, and the irregularity of the calices detract much from its beauty. A. repens is avery commonly met with branched species. A. (?) seria~ toporoides is branched also, but seems intermediate between this genus and the next, Ceenites, for the calices are very sparely set among a greatly developed coonenchyma, are quite circular, and arranged in perpendi- cular order. These Cenites are beautiful branching corals, to be seen in every slab of Wenlock limestone ; and though of small size, are not the least important of fossil zoophytes. The branches of C. jwniperi- nus are round, or nearly so, and bear calices shaped like the Zodiacal sign Aquarius, or, to use a still more familiar simile, like birds upon the wing. The calices of C. interteatus have shorter and less elegant wings; while C. linearis is massive instead of branching, and has
ROBERTS—UPPER SILURIAN CORALS. 61
simple line-shaped calices. These are all of small size. So, too, are the species of the next genus Monticulipora, i.e. “little mountain pore,” from its surface being varied by the elevation of tuberosities. All the species of this genus are branching, save one—M. papillata, whose corallum is thin and incrustating. M. Fletcheri has circular calices regular in size ; while those of M. pulchella are oval, or rarely hexagonal, but differ in size, those occupying the tuberosities being larger than those that come up in the low-lands. Three other species are met with, but rarely.
Next in order is Labecheia conferta, a disc-like coral, which is widely distinct from every other polyparian production; for the calices that come up abundantly to its surface are tubercles in- stead of cups, from their margins folding in upon the centre, and, as a matter of course, their septa are as rudimentary as are those of the Favositide.
Halysites catenularia is another aristocratic coral that does not per- mit others to claim affinity. This is the common “chain-coral,” named so by universal consent, from its calices forming a series of inter- linked loops across the upper surface, like the links of a golden chain. This is a pet species of paleontologists, for M. Milne Edwards has recorded no less than twenty-six synonyms for it en vogue at different times and places. It is abundant in every quarry of Wenlock shale, but the finest specimens come from Benthall Edge.
Now for the parasitical corals, Syringopora bifurcata, S. fascicularis, and S. serpens—three species not easy to distinguish at certain stages of their growth. They lived upon well-to-do shells and corals in those ancient seas, just as species with like habits do now, throwing up here and there a short calicinal tube as they crept over their sur- faces. In after life gemmation out of these produced amass of straight slender corallites, which had an independent existence, and grew tall and comely.
Two others, and the history of our common Wenlock corals is ended. Thecia Swindernana is a massive, but rather thin coral, haying a flat upper surface covered with beautiful star-like calices, whose elegance of design is owing to the development of their septa. The other species, 7’. Grayana is like it in form, but differs in having but twelve septa instead of sixteen or eighteen.
62 THE GEOLOGIST. ,
With one or two exceptions, the whole of the corals I have here attempted to describe may be found within the limits of an hour spent in any quarry of Wenlock shale, or limestone. The few I have omitted to mention have but slight points of difference, and are ac- counted rare; but from a glance at this, every reader or collector will acknowledge that the coral-polyp held no mean place among the workmen of old.
CURRENT NOTES ON MINERALOGY, LITHOLOGY, AND METALLIFEROUS DEPOSITS.
By H. C. Satmon, F.G.S.
Tue October number of the “ Philosophical Magazine” contains a notice, translated from Poggendorff’s “Annalen,” by Professor Gustav Rose, on the isomorphism of stannic, silicic, and zirconic acids. Stannic acid (Sn) forms the mineral Oassiterite, silicic acid (Si) is Quartz, zirconic acid, which Rose considers to be Zr, has hitherto been classed as an earth or oxide, as zirconia, with composition Zr, or Zr. The mineral zircon, hitherto held to be a silicate of zirconia, must now, according to this, be merely considered as an isomorphous compound of one atom of zirconic acid and one atom of silicic acid (Zr + Si). This mineral species has always been remarkable for the variation of hardness and gravity in specimens from different local- ities, which according to this hypothesis may be accounted for by the unequal proportions of the two acids; the heavier and harder speci- mens containing the more zirconic acid, whose equivalent would be 481:20 compared with 384°888 that of silica. In the case of a variety found in Russia by Hermann, composed of two atoms of Zr, with three atoms of Si (Zr? Si), the specific gravity was only 4:06, while — that of the mineral of the ordinary composition varies from 45 to 4°8.
Zireonic acid being thus established, and it being shown that zircon may be regarded as isomorphous with cassiterite (the ordinary
SALMON—MINERALOGICAL NOTES, 63
tin-stone or tin-ore), the former mineral is made, in the Profesor’s reasoning, a kind of middle term to prove the isomorphism of its in- dividual components (silicic acid and zirconic acid), with stannic acid, He considers, in fact, that silicic acid may fairly be considered to be already found in the form of cassiterite, in zircon; and believes it would not be a matter for surprise to find stannic acid in the form of quartz.
Dr. Genth’s paper, in the September number of the “ American Journal of Science and Arts,’’ on the “ Occurrence of Gold’ is very suggestive. After the mass of vague verbiage with which we have been inflicted on this topic, it is really refreshing to find a man who, whether right or wrong, is at least possessed of a definite and com- prehensible idea.
Dr. Genth maintains that the gold found in veins and alluvial de- posits has been carried there in a state of solution; and he brings the following instances to prove that, in those cases at least, such must have been the case. If these are accurately stated, of which there seems every internal evidence, this certainly cannot be questioned :—
“a, Specimen from Whitehall, Spotsylvania co., Va., shows gold associated with tetradymite [telluride of bismuth], limonite [hydrous per-oxide of iron], and quartz. The gold is crystallized in forms be- longing to the rhombohedral system, and showing very distinctly one rhombohedron, scalenohedron and basal plan ;* it is coating tetra- dymite, and is evidently a pseudomorph of it.
“b, The tetradymite of the Tellurium Mine, Fluvanna co., Va., and the native bismuth from the peak of the Sorato, in Bolivia, are frequently interlaminated with gold.
“c, In the upper portion of the ore-bed in the metamorphic slates at Springfield, Carrol co., Md., which near the surface consists of magnetite [magnetic proto-per-oxide of iron], and at a greater depth of chalcopyrite [copper pyrites] and other ores, films of native gold have sometimes been observed coating the cleavage-planes of the magnetite. On close examination it can be perceived that below the film of gold the magnetite is oxidized into hydrated sesquioxide of iron.”
In attempting to establish an hypothesis of this kind, the greatest
* These are the crystalline forms of tetradymite.
64 THE GEOLOGIST.
difficulty, as Dr. Genth truly says, “ presents itself on inquiring into the nature of the solvent.” The doctor believes the noble metal was dissolved as terchloride of gold :—‘ If we remember that the decom- position of pyrites produces sulphuric acid, which, in the presence of the never wanting chloride of sodium and a higher oxide of manga- nese, may liberate small quantities of chlorine, the most powerful solvent of gold, we have at least a very plausible explanation.”
Dr. Genth’s doctrine is that the gold both of veins and alluvial de- posits is derived from the adjoining rocks, where it exists probably in a highly disseminated state ; from these rocks it is removed in a state of solution, and precipitated in concentrated deposits in the veins and among the alluvial débris. The rock in which the metal most frequently occurs is diorite or greenstone [composed of ortho- clase felspar and hornblende]. How it originally came into this rock is not a question entered upon ; the main point being to prove that the gold of alluvial deposits is not derived, as is usually sup- posed, from the destruction of pre-existing quartz-veins, the fact being that they are both equally derivative, the original source being the neighbouring rock.
There are many considerations suggested by the mode of occurrence of gold which weigh strongly in favour of sucha suggestion. In the first place, gold is continually found in alluvial deposits, in consider- able sized nuggets, in districts where no veins are found. In this case the usual theory is that the original upper surfaces, which were rich in auriferous veins, have been removed by denudation, and that the alluvial gold is the remnant of these. But this has the disad- vantage of assuming an hypothesis, for which no good reason can be given, that there is some peculiar law which limits the original pro- duction of gold to the surface, and which is held, with a strange in- consistency, by the same men who fully recognize the more than probability of other metals being derived from beneath. Assuming that the gold is derived from the rock by solution, and that the veins are mere depositories, we have at once at least a plausible reason for the general occurrence of gold only near the surface. It is that the solvent of that metal is somehow or other essentially connected with the atmosphere; so that although gold may exist at all depths, scattered, highly disseminated through certain igneous rocks, it is
SALMON—MINERALOGICAL NOTES. 65
only where these rocks are subjected to a certain atmospheric decom- posing action, by which the gold is dissolved, to be subsequently re- precipitated in a highly concentrated state, that it is found in appreciable quantities. This is strongly supported by the fact that the finding of the gold-deposits is not limited to any arbitrary depth, but generally extends as far as the effects of atmospheric decompo- sition, and no further.
The question of the origin of gold deposits by the deposition of the metal from solution is of course connected with the larger ques- tion of the origin of most veins, either of the metallic or non-metallic minerals, in a similar manner. Omitting Bischoff, who may be con- sidered by some a prejudiced authority, there are many first-rate German mineralogists who hold the doctrine of such an origin for most mineral veins. This scientific infiltration doctrine must not, however, be confounded with a vague mining notion to the same effect, and which would refer such views to a connection with the present drainage of the country, and without any reference to an origin of the metals; an opinion which sometimes takes a form as loose as that expressed by the Roman poet :—
**Tnque brevi spatio, quz sunt effossa reponit Tempus, inexhausti servans alimenta metalli.”
No investigator on the subject of lithology has arrived at more sweeping conclusions as to the origin of rocks than M. Delesse in his “Htudes sur le Métamorphisme.” Although M. Delesse’s labours have been completed for more than a year, it is to be regretted that no complete abstract of them has been yet presented to English readers.* That memoir is too wide a subject to enter upon here ; but a short reference to another paper, by the same author, in vol. xv. of the “ Bulletin de la Société Géologique de France (p. 728), called * Recherches sur lorigine des Roches,’ in which he sums up the conclusions of the investigations detailed in his “ Etudes” may be in- teresting to many.
* M. Delesse’s memoir has been often referred to, and was particularly ably summed up by the President of the Geological Society in his last anniversary ad- dress, which should be consulted by all who wish to read a comprehensive re- view of the recent inquiries on this subject.
VOL. III. I
66 THE GEOLOGIST.
Referring to the agents which, in the interior of the earth, may have aided in rendering rocks plastic, or generally tended to the develop- ment of minerals, he reduces them to four—heat, water, pressure, and molecular action, attributing to the first only a comparatively limited réle in the formation of eruptive rocks.
After describing what he conceives to be the action of these various agents, he thereon founds a classification of all eruptive rocks, according to their mode of origin, into the following divisions:
I. Igneous eruptive rocks. II. Pseudo-igneous eruptive rocks. III. Non-igneous eruptive rocks.
I. Igneous are those which have been reduced to a state of fusion, or at least rendered plastic by heat. They are almost always completely anhydrous, with a cellular structure and a rough feel to the touch, their constituent minerals having a strongly-marked cha- racteristic vitreous aspect; they constitute the rocks regarded as eminently volcanic. As extreme types of this class he especially refers to, trachyte and dolerite.*
II. Pseudo-igneous rocks are those that may have been reduced to a state of plasticity partly by igneous and partly by aqueous action. Water, heat, and perhaps pressure may have combined to contribute to this. Rocks of this class have sometimes a cellular, or even | scoriaceous structure; but their constituent minerals have only a slightly vitreous aspect. They are hydrated, often containing — zeolites, and dividing into prisms or spheroids, and are generally associated with igneous rocks in volcanic regions. As types of this class he refers to retinite (pitchstone or phonolite), basalt, and trap.t These two classes represent those rocks usually called volcanic, |
* Trachyte is a rock containing orthose and anorthose felspar, ferro-magnesian mica, hornblende, and also quartz. By anorthose felspar is designated, in a general way, all the felspar species belonging to the sixth crystalline system. Dolerite is an anorthose and anhydrous lava, composed of anorthose felspar and augite, with sometimes olivine, mica, and leucite.
+ Retinite consists of vitreous orthose felspar, of ferro-magnesian mica, and also quartz rather rarely, and always a large proportion of water, which may rise from 10 to 100 per cent. Pechstein and phonolite are varieties of this rock. Basalt principally consists of anorthose felspar, augite, and olivine, with some- times protoxide of iron, carbonates, zeolites ; and accidentally nepheline, haityne, zircon, corundum, &c., forming a hydrated felspathic paste. Basalt has the
SALMON——-MINERALOGICAL NOTES. 67
TI. The non-igneous rocks correspond to Lyell’s plutonic rocks. Their plasticity was due to the combined action of water and pressure, heat having only played a very secondary part in their for- mation. In them the constituent minerals are devoid of the vitreous aspect peculiar to the igneous rocks; and their structure is rarely cellular, but, on the contrary, generally very compact. They are not associated with voleanic rocks, and are consequently attributable to an entirely different mode of origin. As types of this class he selects granite, diorite, and serpentine.*
Conclusions such as these, so strongly opposed to many of our preconceived notions, are not likely to be received in this country with undue favour. M. Delesse on some points surpasses Bischoff,
same elementary composition as dolerite, differing principally in the presence of a certain quantity of water and volatile matters.
Trap, properly so-called, may pass into basalt, with which it is often associated. An intimate relation exists between the two rocks, but heat only played a very minor part in the formation of trap. Its base is anorthose felspar, which is generally the only mineral possible to be recognized; this is always hydrated, often considerably. It is rich in oxide of iron, and often contains spathic car- bonates. Trap forms the limit of the pseudo-igneous rocks; and although it is intimately connected with basalt, it differs I think in having been formed in a lower temperature.
* Granite, as a type of a large class of rocks, has almost the same mineral composition as trachyte, for it contains quartz, felspars, and micas; but the occurrence and characteristics of these minerals are very different. Its quartz is particularly worthy of remark. In rocks of igneous origin this mineral is often entirely wanting ; now, in granite, on the contrary, it is very abundant, amount- ing to even a moiety in certain rocks, yet the total quantity of silicic acid present is not greater than in trachyte; the greater abundance of free quartz being due to the facilities which the mode of origin of granite afforded this mineral of separating itself from the magma. It must be borne in mind also that this quartz is not only always crystalline, but also always hyaline. The study of the felspars of granite is also very instructive. They are orthose and anorthose, opaque, or at most translucent, never vitreous, and always contain a certain quantity of water, usually trifling in the orthose, but varying from 2 to 100 per cent. in the anorthose. The consideration of the micas and other minerals of this rock are equally instructive in showing its aqueous origin.
Diorite has a very simple mineralogical composition, being essentially formed of anorthose and hornblende, with, at times, protoxide of iron, sphene, ferro- Magnesian mica, and, accidentally, garnet. Diorite greatly approaches granite in its mineral composition. Its metamorphism is analogous, and the one may pass insensibly into the other. Diorite may be considered as formed under con- ditions intermediate between those that have produced trap and granite.
Serpentine has hitherto, of all the eruptive rocks, been the most enigmatical. Its mineralogical characters are so well known, that it is unnecessary to repeat them; but it is particularly distinguished by its large per centage of water, varying from 13 to 100 percent. In this rock all effects of heat have entirely disappeared, and its plasticity can scarcely be attributable to any other causes than water and pressure.
68 THE GEOLOGIST.
and indeed most modern investigators, in the sweeping nature of the power he attributes to aqueous action. He may, in some degree, exaggerate this ; but it is useless to close our eyes to the evidences of the great revolution in opinion, which has recently taken place on the Continent on the subject of the origin of rocks. The doctrine of the force of pure igneous causes, such as students will find in almost every English text-book, has now only a minority of sup- porters in Germany and France. Wide differences of opinion, how- ever, yet exist, which may be expected to give rise to poles investigations and discussions.
a
The following epitome of some of M. Delesse’s more general views will give a notion as to the mixed nature of the causes to which rocks owe their origin :-—
“The problem of the origin of eruptive rocks is one of the most complex in geology, and has given rise to interminable discussions, in which the most opposite systems have seemed in turns to triumph. These revulsions in opinion, sometimes very sudden, are to be attri- buted to the exclusive importance attributed to one or the other agents which have aided in the formation of rocks. In popular language it is said that no two things can be more opposed than fire and water ; but in nature no such antagonism exists, these two agents often acting together. This should be always borne in mind in any inquiries into the origin of rocks. When therefore we speak of an igneous or an aqueous rock, we do not mean to restrict these terms to their exact sense ; we must necessarily attribute to them a mean- ing different from that of common language. When we say a rock is of igneous origin, we do not necessarily say that it has been re- duced to a state of fusion by heat alone: similarly, speaking of an aqueous origin, we by no means limit the causes to the unique action of water. In speaking, therefore, of a cause, it must always be un- derstood that it is only referred to as the principal agent of forma- tion. Of the causes referred to—heat, water, pressure, and molecular action—one may have played a preponderant, but rarely an exclusive part. Molecular action, also, it should be borne in mind, must only be considered as a secondary cause, for it seems to have been induced either by heat, water, or pressure. Hlectricity itself, which accom-
PROCEEDINGS OF GEOLOGICAL SOCIETIES. 69
panies and causes this molecular action, seems to result from these primary causes. As, therefore, on the whole, the chemical and mineralogical composition of rocks varies little, and as it is easy to see that one and the same mineral may have had, at times an aqueous origin, at times an igneous one, we have no reason to be surprised if it is not always possible to trace the rigid limit between rocks which, at first sight, seem the most opposite, such as those engendered by heat or by water.”
PROCEEDINGS OF GEOLOGICAL SOCIETIES.
Gxrotocicat Socrety or Lonpon, January 4, 1860.—Prof. J. Phillips, President, in the Chair.
The following communications were read :-—
1. “On the Flora of the Silurian, Devonian, and Lower Carboniferous For- mations.” By Prof. H. R. Goeppert, For. Mem. G.S.
2. “On the Freshwater Deposits of Bessarabia, Moldavia, Wallachia, and Bulgaria.” By Capt. T. Spratt, R.N., C.B., F.R.S., F.G.S.
3. “On the Rhizopodal Fauna of the Mediterranean compared with that of some of the Italian and other Tertiary deposits.’ By T. Rupert Jones, F.G.S., and W. K. Parker, Mem. Micr. Soc.
The authors presented an extensive table of the Species and varieties of re- cent Foraminifera from several localities in the Mediterranean (worked out from material gathered and dredged by Capt. Spratt, Mr. Hamilton, Prof. Meneghini and other friends), and of the fossil forms from the Tertiary deposits of Malaga (Spam), Turin, Sienna, Palermo, and Malta (communicated by Prof. Ansted, Prof. Meneghini, and the Marchese ©. Strozzi, or supplied from the Society’s Museum) ; also the fossil Foraminifera from Baljik supplied by Capt. Spratt, and those of the Vienna Basin as elaborated by D’Orbigny, Czjeck, and Reuss. The recent Foraminifera, tabulated in eleven columns, were illustrative of the range of the respective species and varieties in different zones of sea- depth, from the shore to one thousand seven hundred fathoms, and of the rela- tive size of the individuals, and of their proportional paucity or abundance. Among the seventeen columns of fossil Foraminifera, some were very rich in Species and varieties, especially in the case of the Siemnese clays, the Malaga clay, and the Vienna basin. From the evidence afforded by the comparison of the fossil with the recent Foraminifera, the Siennese blue clays of S. Cerajolo, 8. Donnino, 8, Lazaro, and Coroncino were regarded as having been deposited in yarious depths of from forty to one hundred fathoms ; so also the clay-beds of Malaga and of the Vienna basin. A blue clay from S. Quirico was probably formed in about two hundred fathoms; a blue clay from Pescajo, on the con- trary, was the deposit of a shallow estuary. A sand from Pienza, and others from Montipoli, Castel’Arquato, and San Frediano, contain Amphistegina, and were probably deposited in from ten to twenty fathoms water. As the Amphistegina appears now to be extinct as regards the Mediterranean, these Amphistegina-beds, and others at Palermo and in the Vienna Basin, may be of miocene age. Another Siemnese clay from Monti Arioso is of shallow water
70 THE GEOLOGIST.
formation. From Turin some shelly sands, of pliocene age, were defined as containing a group of Foraminifera similar to those now living on the western shores of Italy; and the Palermo deposits are, for the most part, not very dis- similar. The Heterostegina-bed at Malta, formed probably in rather shallow water, is characterized by a species now absent from the Mediterranean. The tertiary deposit from Baljik appears to have been a shallow water deposit, characterized by some forms peculiar at the present day to the Red Sea; a condition that is also indicated by some of the Viennese deposits.
Liverroot Gxotoctcat Socrety.—The first meeting of this society was held on Tuesday, the 10th of January last.
Prof. Phillips, President of the Geological Society of London; Prof. Ram- say, Director of the Geological Survey of Great Britam; Prof. Jukes, Director of the Geological Survey of Ireland; Prof. Morris, F.G.S. ; and 8. J. Mackie, Esq., F.G.S., F.S.A., were elected honorary members.
The President, Henry Duckworth, Esq., F.R.G.S., F.G.S., then read the inauguration address. After congratulating the members on their assembling together for the first time as a constituted body, he proceeded to point out the objects of the society.
The geology of Liverpool and its immediate neighbourhood was next touched upon, and afterwards that of the surrounding country, especially of North Wales, the President calling particular attention to the comparative ease with which such deeply interesting localities as Church Stretton, Coal- brookdale, and Ludlow—the portals of the Silurian system—might be reached.
The President then gave a resumé of the progress of geological science during the past year.
A paper was then read by the Secretary, G. H. Morton, Esq., F.G.S., “On the Basement-bed of the Keuper Formation in Wirral,* and the South-west of Lancashire.”
Interesting specimens of fossils and minerals were exhibited at the meeting by various members.
[The abstracts of Prof. H. R. Goeppert, Capt. T. Spratt, and Mr, Morton’s paper will be printed in the next number. |
NOTES AND QUERIES.
On tHe Lower Sinurtan Rocks in tHE Sourn-Hast or IRELAND, AND on A Human SKELETON IN AN BLEVATED SrA-Marcin.—Dnar Sin,— Iu the year 1840, when persevering in what was considered at the time a hope- less task—that of searching for fossils in the contorted old schistose and slaty rocks so extensively developed in the counties of Waterford, Wexford, and Kilkenny—lI at length discovered at Duncannon, in the county of Wexford, a patch of rocks which I considered might be referred to the Llandeilo forma- — tion. Although the correctness of this view has been questioned, and it has been broadly asserted that a// the Silurian Rocks in the south-east of Ireland
* Wirral is the western extremity of Cheshire.
NOTES AND QUERIES, 71
are confined to the Caradoc group, yet I believe that it will be eventually acknowledged that the fossils from Duncannon are Llandeilo types, such as Calymene duplicata, Beyrichia complicata, Lingula attenuata.
the Silurian mollusca from Duncannon, except the black horny Lingula, have a white silky appearance, in striking contrast to the dark matrix in which they are imbedded. ‘This, I imagine, is owing to the shells having been at a remote period slowly and partially calcined by the action of the heat from the igneous rock in the vicinity. :
The mineral character of the rock also agrees with the Llandeilo flags and dark-coloured schists so well developed in Wales. I therefore wish to record my view of the age of similar dark-coloured rocks at Duncannon, more espe- cially as I cannot without great difficulty refer them to the Caradoc series, a patch of which I discovered on the opposite shore of Waterford Haven. The trilobites which I obtained there were lent to be described in a work ona northern Irish county then publishing.
It is to be regretted that, in Portlock’s Report of Londonderry and Tyrone, the trilobites which I obtained at Newtown Head are stated to have been dis- covered by me at Tramore. The mistake no doubt arose from there being two localities named Newtown Head, one near Tramore, and the other situated between Passage and Woodstown, on the western shore of Waterford ape which I fully explained at the time, but which was unfortunately lost
ight of.
itouch a paper of mine, giving a brief account of these fossiliferous strata had been read at a meeting of the Geological Society in 1841, the discovery of those Silurian rocks has been erroneously ascribed to the Ordnance Geological Survey in Ireland (Mem. Geol. Sury., Decade 2, pl. x., p. 4); and one of the very trilobites which I had lent, has been dedicated by Mr. Salter (at page 3, pl. 7, decade No. 2), to the author of the work above alluded to, as its dis- coyerer. So far from the Government Surveyors having discovered the fossiliferous rocks in question, they were wholly unknown to the Survey until I pointed them out to Colonel James, R.H., in the spring of 1841. Well might the Surveyors pass them by, for they can only be approached with an ebb tide; and as they are quite level with the shore, the adjacent cliff being destitute of fossils, they did not attract notice till the publication of my paper.
Se ciclly these rocks will be covered by the accumulation of the silt and sand which are deposited at every tide, so that all trace of them will be lost.
Continuing my search for organic remains on the Waterford side of the estuary, [ was rewarded, as above indicated, with the discovery of lower Caradoc rocks of limited extent, which, as I have related,