Ge ea tk Po pa l= tetin pte fer agp tthe it the Fo i-th ts ith fhe 2 Fr Gita thr Fh ths haf Has sari geicteet-iba te Ure Oratotesta on Cater oa tat re peine het ok Gnfatrethetn oe ‘ ( a pat Rather a He ate inne > ona tat ative nt tn : poset fe pac | he Arte Satin nH fom hte Deiat Mo : - e Setine a ws Bae aw : ° the aR = Ba tn Be Me Teh Pe GR Ee ta he ae Sn rm Pe ta Hoe PIO Fm Mw So De Me ee Shido a Shel ~ Pte PAR etna data tate im tee nit Patten Yon wa nhs Me Me Ho FS ie he ee Maat See ete t= ety Safe oe eee fet i pn $0 Ki Rn Re Eten Se Pn tae Pn Te ne mn i en toe BRAG Sef - S- a a ee Se anh NM en at ee ee ee Soe ll Neg aM we fi s aw Tk THE QUARTERLY JOURNAL OF THE GEOLOGICAL SOCIETY OF LONDON, EDITED BY THE ASSISTANT-SECRETARY OF THE GEOLOGICAL SOCIETY. VOLUME THE SIXTH. 1850. PART THE FIRST. PROCEEDINGS OF THE GEOLOGICAL SOCIETY. LONDON: %. 2 a LONGMAN, BROWN, GREEN, AND LONGMANS. AéJiguay Ws eat PARIS :—FRIED. KLINCKSIECK, 11 RUE DE LILLE; BAUDRY, 9 RUE DU COQ, PRES LE LOUVRE; LEIPZIG, T. O. WEIGEL. NEW YORK :—WILEY AND PUTNAM, 161 BROADWAY. SOLD ALSO AT THE APARTMENTS OF THE SOCIETY. MDCCCL. List OFFICERS OF THE GEOLOGICAL SOCIETY OF LONDON. Evectep Frsruary 1850. Presivent. Sir Charles Lyell, F.R.S. & L.S. Gtce-PrestVents. Sir Henry T. De la Beche, F.R.S. & L.S. Prof. E. Forbes, F.R.S. & L.S. D. Sharpe, Esq. F.L.S. Sir R. I. Murchison, G.C.St.S8. F.R.S. & L.S. Secretaries. William John Hamilton, Esq. John Carrick Moore, Esq. M.A. Foreign Secretary. C. J. F. Bunbury, Esq. F.L.S. Creasurer. John Lewis Prevost, Esq. COUNEIL. Rev. P. B. Brodie, M.A. G. A. Mantell, LL.D. F.R.S. & L.S. Charles Darwin, Esq. M.A. F.R.S. The Right Rev. the Bishop of Oxford, Sir P. Grey Egerton, Bart. M.P. F.R.S. F.R.S. Earl of Enniskillen, D.C.L. F.R.S. Lyon Playfair, M.D. G. B. Greenough, Esq. F.R.S. & L.S. Samuel Peace Pratt, Esq. F.R.S. & L.S. William Hopkins, Esq. M.A. F.R.S. Prof. A. C. Ramsay. Leonard Horner, Esq. F.R.S. L. & E. S. V. Wood, Esq. L. L. B. Ibbetson, Esq. Assistant-Secretary, Curator, and Librarian. T. Rupert Jones, Esq. TABLE OF CONTENTS. Page AusTEN, R. A. C., Esq. On the Valley of the English Channel.... 69 On the Age and Position of the Fossiliferous Sands and Gra- Seem ioe RAUENIEO OW St. shes teint Rov RP ele aie ® fe ele a ne Ae alee > wer ohs 454 Binney, E. W., Esq. Remarks on Sigillaria and some Spores found maeHMed In pie IMside OL its NOOLS 2:2... 4. 22-002 -.+s ee es nee 17 Bropig, Rev. P. B. On certain Beds in the Inferior Oolite, near Mm MUTA YAN etencite 5c craters seer en orserie cera ange case ee Sits wees 239 Brown, R., Esq. Section of the Lower Coal-Measures of the Sydney Coal-Field, in the Island of Cape Breton. ............e00 es eeee 115 Buckman, Prof. J. On some Fossil Plants from the Lower Lias.. 413 CARPENTER, W.B., Dr. On the Microscopic Structure of Nummu- itemOrurvolites. and OTOULOLGeS”.oiis nc so sc cece ees ve ve es 21 CiLEGHORN, J., Esq. On the Till near Wick, in Caithness........ 385 CummMInG, Rev. J. G. On the Tertiaries of the Moray Firth...... 10 CuNNINGTON, W., Esq. Ona Section of the Lower Greensand at Ce TEMP SIZES tt, ci) oA cee ok coe ope ewe aie A Bae shacars © ele gee se 453 Darwin, C., Esq. On British Fossil Lepadide ................ 439 Davis, J. E., Esq. On the Age and Position of the Limestone of Midvaedteat Presteion, Squth Wales 1.3. .....20+se8p2 ess see 432 Dawson, J. W., Esq. On the Metamorphic and Metalliferous Rocks GaP TANDEM NCA) SCOLIAY «ccs csv edie coat se oes, sieve «ee 48 ai so 24) r16 347 Dr LA ConpDAMINE, Rev. H. M. On the Tertiary Strata and their Dislocations in the neighbourhood of Blackheath .............. 440 Dr Zieno, Count A. On the Stratified Formations of the Venetian uN PRMEUPEUY ote! cee oe eo Valais) ces apes coave dee chant ete tots 6 Oe Hee oye 422 Ecerton, Sir Philip Grey. Palichthyologic Notes. No. 3—On fa PEMREEOTUCIMELELETOCCTCU, fone oans i 6 ow sapen sted y cee bk oe vase ose 1 EzQuERRA DEL Bayo, Don J. On the Geology of Spain........ 406 FuetTcHeErR, T. W., Esq. On Dudley Trilobites, Part 1........... 235 On Wadley Trilobites,)Parti2yrs ol eG ecient ter ceeds hea 402 Forses, Prof. E. Note on Fossiliferous Deposits in the Middle sy MIRON MD Ne AA LATA ooh 2d, 800) eae cs Ely /ellovos ail affevedo Ghd b sepiplergy Ed o 343 Hami.ton, J. W., Esq. On the Occurrence of a Freshwater Bed of Marlanithe. Mens of Cambridgeshire ,.. ,. .:. 5 series see pee eyes 451 HARKNESS, R., Esq. On the New Red Sandstone of the Southern Poriuomortne. Vale gt the Nii i. oy sit yas p ajo ple ls eal seo ow « 389 Hopkins, Evan, Esq. On the Structure of the Crystalline Rocks of Eieranides aud them Cleavage Planes .... 54. ./2 esse eep oe 364 Horner, L., Esq. On the Discovery, by Prof. Lepsius, of Sculp- tured Marks on Rocks in the Nile Valley in Nubia, indicating that within the Historical Period the River flowed at a Higher Level Siaenie VOU EMU TMCS * punctay ea vou sce ais cc eee ool Ce hbo eae 384 1V TABLE OF CONTENTS. 3 Page Lycett, J., Esq., and J. Morris, Esq. On Pachyrisma, a fossil genus of Lamellibranchiate Conchifera ........ 0 HbA As ok Netenee 399 LYELL, Sir Charles, President. Anniversary Address in February PB SO mali a ecs, aise a eke cases ers tage eee ne eetoee keeles eee ee XXVil On Craters of Denudation, with Observations on the Structure and. Growth of Voleanie Comes................ +0. . 0 6 eee 207 MAnTELL, Gideon A., Esq. On the Remains of the Dinornis and other Birds, and the Fossils and Rock-Specimens recently collected by Mr. W. Mantell in the Middle Island of New Zealand ........ 319 MAnrTELL, R.N., Esq. On the Strata and Organic Remains exposed in the Cuttings of the Branch Railway from the Great Western Line near Chippenham, through Trowbridge, to Westbury in Wiltshire.. 310 Moors, J. C., Esq. On some Tertiary Beds in the Island of San DOMINGO en oi ojo ss ease 5 agatape, ele © our a 4 elke ake en 39 Notice of the Occurrence of Marine Shells in the Till ...... 388 Morris, J., Esq., and J. Lycetrt, Esq. On the Occurrence of Mammalian Remains at. Brentford... .i,...6. - 4+ +<.=4 «5 201 ——. On Pachyrisma, a fossil genus of Lamellibranchiate Conchifera 399 Mourcuison, Sir R.1. On the Distribution of the Superficial Detri- tus of the Alps, as compared with that of Northern Europe ...... 65 On the Earlier Volcanic Rocks of the Papal States and the adjacent parts ‘of Ttaly oo...) 022. sees « Spee eo 281 On the Vents of Hot Vapour in Tuscany, and their Relations to Ancient Lines of Fracture and Eruption’... ...... 0... 0seneee 367 Nicou, Prof. J. On the Silurian Strata of the South-East of Seotland 53 ——. Notice of the Occurrence of Coal near Erzeroom ........... 367 Prestwicu, Joseph, Jun., Esq. On the Structure of the Strata be- tween the London Clay and the Chalk in the London and Hamp- shire ‘Tertiary Systems’... ./02 24.0 ses ees ole oe 252 Ruxton, Lieut. G. F. On the Volcanic Rocks of Northern Mexico 251 SHARPE, D., Esq. Remarks on the genus Nerinea, with an Account of the species found m Portugal <.....°. 7... .. 32... 101 On the Secondary District of Portugal which hes on the North of the, Tacs». sic) oss Jes ae wert scien Us Ce iene ee 135 Sismonpa, Prof. E. On the Discovery of a nearly perfect Skeleton of the Mastodon angustidens near Asti in Piedmont ............ 252 Smiru, J., Esq., of Jordan Hill. Note on the Shells found m the Till) by, Mr. Cleghorn... 24 . sagiecils/ajecleb sl a se he 386 ——. On the Occurrence of Marine Shells in the Stratified Beds below thie ll, eek. aise. ee Soe saci hs oich le Soci gee = ee 386 STEVENSON, W., Esq. Ona Gap in the Greywacke Formation of the Eastern Lammermutirs filled by Old Red Sandstone Conglomerate 418 Stowe, W., Esq. Ona Cutting im the Railway near Buckingham.. 134 STRICKLAND. H. E., Esq. Notes on a Section of Leckhampton Hill 249 Ty tor, A., Esq. On the Occurrence of Productive Iron-Ore in the Eocene Formation ot Eamipsbire®.3 2 00%.'. 03.000. sat oe 133 Weston, C. H., Esq. On the Diluvia and Valleys in the Vicinity of Bath... wars cs vs AAO @ CRO EG ae aieie © ev ries ree 449 LIST OF THE FOSSILS FIGURED AND DESCRIBED IN THIS VOLUME. [In this list, those fossils, the names of which are printed in Roman type, have been previously described. ] Name of Species. Formation. Locality. Page. PLANT. (9.) Cupressus? latifolia. Woodcut, f. 5.{ Lower Lias ...| Gloucestershire ...| 415 BIGEE 1 NWV.GOOCUts sf.) 945) asis-0o% cs ncnnc Lower Lias ...| Gloucestershire ...| 417 Equisetum Brodiei. Woodcut, f. 1...) Lower Lias ...| Gloucestershire ...| 414 Naiadita lanceolata. Woodcut, f. 2.| Lower Lias ...| Gloucestershire...) 415 obtusa. Woodcut, f. 3 ......... Lower Lias ...| Gloucestershire ..., 415 petiolata. Woodcut, f. 4 ...... Lower Lias ...| Gloucestershire...) 415 Sigillaria, crucial sutures at base of.| Coal-measures.| Yorkshire ......... 19 Woodcuts, f. 5-8. , spores found in root of. Wood-| Coal-measures.) Wigan ............ 20 cut, f. 4. , vascular axes of. Woodcut,| Coal-measures.| Wigan & Ashton-| 19 f. 1-3. under-Lyne. Umbellifer ? Woodcut, f.8 ......... Lower Lias ...| Gloucestershire...) 417 Zamites gramineus. Pl. xxvi.f.7...| Jurassic ...... POntugall Gat -sis.n. 199 DiaToMacez&. (6.) Actinocyclus. Pl. xxix. f.9 ......... Tertiary < Ja..0 | New Zealand ...... 332 Pinnularia. Pl. xxix. f. 8 .........00. Mertiary s.20.. | New Zealand...... 332 Pyaidicula. Pl. xxix. f. 10.....-...00 Tertiarye sas cx New Zealand ...... 332 Palycystma. Pl. xxix. f. 1]) ...00000. Tertiary... New Zealand ...... 332 Stauroneis Zealandica. Pl. xxix.f.4,5.| Tertiary ...... New Zealand ...... 332 Surrirella. Pl. xxix. f. 6,7 ..0...0. Tertiary... New Zealand ...... 332 FORAMINIFERA. (15.) Marginopora (Orbitolites), structure| Recent ......... Australia ......... 31 of. Pl. vii. f. 24-29. Mummmulina, supposed animal of. Play s..tesccescecessecl|-odesv.cocccdecsciesseses 27 iii. f. 5. complanata, structure of. Pl. iv.| Tertiary ...... PEANGCOn abc5, bcsches 25 fete. vit. 17. levigata, structure of. PI. iii.| Tertiary ...... Bracklesham ...... 22 f.1-4. Pl.iv.f. 6-8. Pl. v. f. 15, 16. obtusa, structure of. Pl. iv. f. 11.) Tertiary ...... Cutchie nse. & 37 Orbitoides, structure of. Pl. iv. f. 9.| Tertiary ...... SEMIACHS cen asionwoee 35 PRy. f. 13,14. -———, structure of. Pl. iv. f. 10...... Pertiary 2.0. dirdiae? a5. . 36 , structure of. Pl. vi. f. 18...... Mertiany-y..toct Indias) seeso.ane}. 34 strucwure Of Pl. vit. 19is. 5 Wertiary ...... NEM es fee andane 35 msimuctune of. PRivis f., 22... 2. Tertiary ..5..2 BRALIEZ Maas eee'ch sce: 34 Mantelli, structure of. Pl. vi.| Tertiary ...... Alabama............ 32 £120; 9R. Pl. vii: f.. 31: Prattii, structure of. Pl. viii.| Tertiary ...... BigritZ..0Fs..i8F.. 33 f. 32-37. complanata, structure of. Pl. vi.| Tertiary ...... Paris Basin ...... 31 fa2ar Pl. vil. t. 30. Romculoria. Pl. XXi%ef. 1 oie Cretaceous ?...| New Zealand...... 330 aciculata..- Plexis, fits seas. Cretaceous ?...| New Zealand ...... 330 elongates Wit wxixs ts 24. in8. ; Cretaceous ?...) New Zealand ...... 330 vi Name of Species. Formation. ZoopuHyta. (8.) Cereopora. Pl. xxviii. f. 9-11 ...... Cretaceous ?... Ototara. P|. xxviii. f. 4-7 ...| Cretaceous ?.. Eschara. Pl. xxviii. f. 4&8 ....00... Cretaceous ?... Gorgonia, spicule of. PI. xxix. f. 12.| Cretaceous ?... Graptolites Griestoniensis. Woodcut,| Silurian ...... fi. Manon. Pi. xxviii. f. 12-14 ......... Cretaceous ?... Pustulopora Zealandica. Pl. xxviii.| Pleistocene ... £.°20; 21. Turbinolia? Pl. xxviii. f. 18,19 ...| Pleistocene ... ECHINODERMATA. (6.) Echinus Olisiponensis. P\. xxv. f. 1. | Hippurite limestone, Echinopsis? subuculus. TUGG: PVR: 1s O ace snacadace oes Brissus PA] xy: £2105 scutiger. Plaxxyoin5 erceetess CRUSTACEA. Pl. xxxii. f. 1-5... Pl. xxxii f. 6-10... Pl. xxvii. f. 10. Cybele punctata. variolaris. Lichas Barrandii. Pl. xxvii. bis, f. 5. —— Bucklandi. Pl. xxvii. f. 1-5. Pl. xxvii. bis, f. 1. Grayii. Pl. xxvii. f.8. Pl. xxvii. bis, f. 3. —— hirsutus. Pl. xxvii. f. 6, 7. Pl. xxvii. bis, f. 2. Salteri. Pl. xxvii. f. 9. Pl. xxvii. bis, f. 4. Mo.Luvusca. Pl. xxvi. f. 2 Spirifer Beirensis. Pl, xxvi. f. 3. Terebratula Beirensis. Gaulteri. Pl. xxviii. f. 2,3 ., Ostrea prelonga. Pl. xx.f. 4 pustulosa. Pl. xxiv. f. 4 Exogyra Olisiponensis. Pl. xix. f. 1, 2. eeeececece Dianchora? bicornis. Pl. xxvi.f. 4, 5. Pecten (Janira) inconstans. PI. xix. 2. Lusitanicus. Pl. xxiv. f. 3 Perna Lusitanica. Pl. xxiii. f. 7,8... ? fragilis. Pl. xviii. f. 4 Pl. xxiv. £1, 2 Pl. xxiik f, 3-6 ..; PI; xxiii. £2: polita. Gervilia Fitton. Sobralensis. ...{ Jurassic Pl. xxv. f. 2.| Subcretaceous. Diadema Lusitanicum. Pl. xxv. f. 4.| Subcretaceous. Subcretaceous. (Hemiaster) subdepressus.| Subcretaceous. Hippurite limestone. (7.) SGTIAN! Noo. Silurian Silurian Silurian eecces Silurian Silurian Silurian (86.) Jurassic .| Cretaceous °... Suberetaceous. Subcretaceous. Hippurite limestone. Jurassic Hippurite limestone. .| Suberetaceous. Subcretaceous. Hippurite limestone. Suberetaccous. Suberetaceous. Subcretaceous. Locality. New Zealand ...... 330 New Zealand ...... 329 New Zealand ...... 329 New Zealand ...... 329 Scotland <5. ..59e6e 63 New Zealand ...... 330 New Zealand ...... 331 New Zealand ...... 331 Tasbon | . ...0saene 186 Bortogals...s. «sem 186 Name of Species. Vil Formation. Avicula Olisiponensis. PI. xviii. f. 3. Hippurite Mytilus Betrensis. Pl. xxvi. f. 1 Morristt. PVR 8.0" w.c..0 008 Arca consobrina. Pl. x.f. 12 ...... — Olisiponensis. PI. xiv. f. 1 subtetragona. Pl. xxx.f.5 ... Pectunculus acuticostatus. Pl. x. ey lay Nucula (Leda) Phillipsii. Pl. xxx. nee Trigonia Lusitanica. PI. xxii. f. 4... Diceras Favri. Pl. xv. f.3. Pl. xx. f..9. Caprinula Boissyi. Pl. xvi. f. 1-3... Wrevis, Pl, xvii: fy 2 nvcsees — d’Orbignii. Pl. xviii. f. 1,2... — Doublieri. Pl. xvii. f.3,4...... Astarte? discus. Pl. xxi. f. 4, 5 @Garinata. Pl. xxx h 2 ......0ia% Pachyrisma grande. Woodcut ...... Cardium corrugatum. Pl, xiv. f. 3...) Hippuritelime- stone & Sub- cretaceous. —— Olisiponense. Pl. xiv. f.4...... Hippurite limestone. Hattense.. Pl.ixj fd svswewsvs Perthary..<..8 Cyprina globosa. Pl. xv. f. 1......... Hippurite limestone. eormdia El. XV. 8. 2 ice: suc ccsses Hippurite limestone. securiformis. Pl. xxii. f. 1-3 ..| Subcretaceous. Artemis cordata, P\. xxi. f.3 ...... Subcretaceous. elegantula. Pl. xiv. f.2......... Hippurite limestone. moelevans. PIR: £.O) wscssenes Subcretaceous. Tellina Sobralensis. Pl. xxi.f.1 ...| Tertiary ...... Corbula Edwardi. P\. xxi. f. 2 ...... Subcretaceous. Waxyerr Dit Mets 2) ake eeesens Subcretaceous. ? Macneillii, Pl. xxx. f. 4...... Kelloway rock. Dentalium. Pl. xxviii. f. 15 ......... Pleistocene Petaloconchus Domingensis. Pl. x.| Tertiary ...... co. Conus symmetricus. Pl. ix. f. 1...... Dentiaty cee. eaenatus, Pl. ix. £2. 00022: Tertiary’ ....:. Cyprea Henikeri. Pl. ix.f.3 ...... Mertiany? 2202 Voluta pulchella. Pl. ix. f. 4......... Mertiaty sscns. Maura Henikert. “Pl. 1x. f. 5) .......-0. Werhiary s..s6. Columbella venusta. Pl. ix. f.6...... Tertiary . ...... Cassis suiciferad. Plex. £1 13% Tertiary =..... Cassidaria levigata. Pl. x.f.2...... Pextiary< 23:%.- limestone. SHEEASSIC. 1) ome Subcretaceous. WMeridaryy. ....2. ...| Hippurite limestone. Kelloway rock. Pertiary” 3..%-. Oxford clay ... Subcretaceous. Hippurite limestone. Hippurite limestone. Hippurite limestone. Hippurite limestone. Hippurite limestone. .| Subcretaceous. Kelloway rock, and Oxford clay. Great oolite ... ...| New Zealand see Locality. IGiSDOM seneeeeeaete: Portugal’. t.4-. 208 San Domingo...... Thisbon 2 -eeeukees. Trowbridge ...... San Domingo...... Trowbridge ...... Portugal 7. .30t5.0003 HiSDON” seeceaterasd TishOnh "sof cscs Portugal’. .A0c.4: Wilts & Yorkshire. Minchinhampton . Portugall..... 00: isbow i ceteeek TAsbony ssss.5scees POnbuealecasscces,. a. POrtuedl 55 -cses ee OLGUGAleaptaest =: PORGUP All, secaeee shes POECUCA ss somes aces POREUG@ AL step. o 2. cones PORCUBALS ooase coats Trowbridge San Domingo...... San Domingo...... San Domingo...... San Domingo...... San Domingo...... San Domingo...... San Domingo...... San Domingo...... San Domingo...... 182 182 182 177 177 177 190 181 181 318 331 51 44 45 45 46 46 46 47 47. vill Name of Species. Formation. Locality. Page. Oniscia Domingensis. Pl. x. f.3 ...| Tertiary ...... San Domingo...... 47 Strombus Haitensis. Pl. ix.f. 7 ...| Tertiary ...... San Domingo...... 48 proximus. Pl. ix. f. 8 Meritaryorasss=: San Domingo...... 48 — bifrons. Pl. ix. f. 9 Pertiary .<..3! San Domingo...... 48 Typhis alatus. P\. x. f. 4 Tertiary... ,5...2 San Domingo...... 48 Murex Domingensis. Pl. x.f.5 ...| Tertiary ...... San Domingo...... 49 Pleurotoma Henikeri. P\.x.f.6 ...| Tertiary ...... San Domingo...... 50 venusta. Pl. x. f. 7 fertiary 3.22: San Domingo...... 50 Solarium quadriseriatum. Pl. x.f.8.| Tertiary ...... San Domingo...... 51 Bulla granosa. Pl. x. f. 10 Wextiary /2sc.u. San Domingo...... 51 Natica Lusitanica. Pl. xxiv. f. 5 ...| Subcretaceous.| Portugal............ 192 Nerita turbinata. Pl. xxiv. f. 6 Subcretaceous.} Portugal............ 192 Neritina bicornis. Pl. xxiv. f. 7 ...| Subcretaceous.| Portugal............ 192 Pyramidella sagittata. Pl. xx. f. 8...) Subcretaceous.| Portugal............ 193 Rostellaria Coste. Pl. xx.f. 1 Subcretaceous.| Portugal............ 193 Turbo Munde. Pl. xx. f.7 Subcretaceous.| Portugal............ 194 Terebra obconica. Pl. xx. f.5 Subcretaceous.| Portugal............ 194 Turritella Cintrana. Pl. xx. f.6 ...| Subcretaceous.| Portugal............ 194 rosea. Pl. xxviii. f. 16, 17 Pleistocene ...| New Zealand ...... 331 Nerinza Archimedis. Woodcut, f. 1.| Subcretaceous.| Portugal............ 103 Dupiniana. Woodcut, f.2 ...| Inferior Neo-| France ............ 103 comian. — grandis. Woodcut, f. 3 Subcretaceous.| Portugal............ 104 Bruntrutana. Woodcut, f. 4...) Subcretaceous.} Portugal............ 104 nobilis. Pl. xii. f. 1 Hippurite Portugal so..a2eesne 111 limestone. — Titan. Pl. xii. f. 3 Subcretaceous.| Portugal........+... 112 annulata. Pl. xiu. f. 1 Subcretaceous.} Portugal............ 112 —— turbinata. Pl. xii. f. 2 Subcretaceous.| Portugal............ 113 Eschwegii. PA. xiii. f. 2 Hippurite Lisbon ] New Holland 7:3 23...s3e-ceeeee Burman peer soacgeeee Worl Greeret: 2 Chita) 5s). thse eaeseree se eee Such sets of specimens which it seemed desirable for the Society to preserve, but which being very seldom referred to need not have drawers appropriated to them, have been packed up in parcels, care- fully labelled, arranged geographically and placed m the crypt. List of Specimens in the Crypt in parcels from the Foreign Collection. Parcels. Parcels. A.X. Sweden 20s. .00.00.5°2-) BEX. Granada 22-22 1 >» Davaria ‘U.S eee 1 BX. Norway) .c ee ones 4 » Spain >. oe ] PMI ut Neg ic NR a ae ee ote » south of Spam 222. » Switzerland.: [ote 1 B.O. Cape of Good Hope .. 1 is SSt» Helena. 23S 1 G. Switzerland, Canton i a) “iEslevor Branee 572.2% 1 de: Valais... {45 », Switzerland, Canton 9 C.X. Russia, Crimea ...... l de Vaud... C:OF Capene Verde ie S). 01 5, switzerland, se > 1 » Ascension Island .... 1 Tessmo “<0 at id Madeiraa so doe aa 1 | G.O. Canada... . =. See 1 By) (Piedmont 722%, 1 | H. Euganean Hills ...... ] H.O. New England.......-. 2 pS; (Chanoun ) 490 222 1 » Newfoundland ...... 1 F. Duchy of Sayoy ...... 2 » New dersey.. .c7 ar. ANNUAL REPORT. iV; Parcels. Parcels, ME Sy ONTLA wavs, tie chet) 4) ) > +3 33 5%) > Asia. Australia, &c. Africa. v1 ANNIVERSARY MEETING. The Council having directed that the three first of these divisions ~ should be arranged stratigraphically, and the five last should be placed in geographical order, the Committee proceeded so to arrange them, adhering strictly to the rule laid down by the Council, that the spe- cimens from different countries or important districts should not be mixed in the same drawer. The following is the progress which has been made in this part of the labour :— Europe, Tertiary Series. —The following drawers have already been arranged in order :— Cabinet A. lst drawer ........ Fossil shells from Uddevalla. 2nd & 3rd drawers.. Breccia from Gibraltar. 4th drawer ........ Shells from the Loess. Rhine. 5th to 9th drawers.. Shells from Sicily. Pliocene. 10th & 11th drawers Shells from Touraine. 12th drawer!’ 2020). Shells from Prov. d’ Anvers. 7 OFaAWeErs ese, Shells from Bordeaux. Miocene. Cabinet B. 5 drawers. Shells from Turin. Miocene. eh ei, Impressions of Leaves and Fish in the Brown Coal of Germany. 8 es Fossils, various, from Malta and Gozo. Cabinet C. 4 drawers. Rocks and Fossils from Malta. 2 a ————___—_—_—_—_—_——~ Gibraltar. ] 5s ee yea 1 pe So ee EES 20 yl —_ Spain. 2 . Ss ee Pree 1 5 ———______-—-——- Belgium. Cabinet D. 2 drawers. Shells, &c. from Lisbon. S 7s Plants, Insects and Fishes from the freshwater deposits at Aix in Provence. 2 ,, Vegetable Impressions. Samos. 1 és Freshwater Shells from Smyrna. 2 5 ze Fish, &c. from the Province of Verona. me Shells, &c. from Malaga. Cabinet E. 1 drawer. Shells, &c. from Bassano, &c. Eocene. ile? ae Marine and Freshwater Shells from the Paris Basin. Centre Cabinet. Nos. 9 to 15 inclusive. Jaws, Teeth, Bones and Casts of Bones from the Eocene freshwater deposits in the neighbourhood of Paris. No. 16. Bones and teeth of Ursus Speleus from the Caves of Echenoz near Vesoul, France. ANNUAL REPORT. Vii Europe, Secondary Series, arranged as follows :— Faxoe Limestone... 1 drawer. Schneeberg ...... Das. Maestricht ...... 7) iz. Loopmyues: . Conchifera.. 3 Mollusea .. 1 Belo... |. 9 ,, from Louisberg, Aix-la-Chapelle, &e. WTaNCe «=. 22s... 11 ,, ~~ viz. Cretaceous and Oolitic 7 | Fae igen ene eet 18) AEG URE eames ie gatas fe 3 Neuchatel ...... 1 ,, Neocomian. Sarda ..)..... 2 ,, Cretaceous. Hanover ........- 1 ,, Muschelkalk. Lays it sehr ae do. Phuringia, ..... Le ey. do. Mansfeld ........ 2 ,, Copper-slates. IDAVATIA 5 ur. wee 15 ,, Mostly Oolitic. Wurtemberg 4 ,, Oolitic. [LeU ee Cee ee do. Porvugal ;....... 1 ,, Cretaceous. MMUISSIA 5... 0h. -- Beis Cine: an 2 ,, Cretaceous. Sicily LAN EN I Uta Eschweller ...... 1 ,, Formation doubtful. NGG) cs ss ROE do. do. The above are already in sufficient order for convenient reference ; most of the specimens have the localities marked and some of the Species are named; but the whole series requires a farther review, especially with a view to discarding useless specimens and duplicates. Hurope, Paleozoic Series.—Fifty-two drawers belonging to this series are already placed in the cabmets; a few of these had been arranged in excellent order by Mr. Lonsdale, but the rest will require considerable labour to bring them into order, as they are crowded both with specimens of no value and with duplicates to such an extent that the Committee think it useless to offer a list of them in their present condition. When arranged, this part of the collection will be fully equal in interest to the other series, containing very rich collections from the Silurian formations of Norway, Sweden and Russia, the Devonian beds of the Rhenish Provinces and the Devonian and Car- boniferous formations of Russia, besides minor collections from other countries. British North America.—Twenty-seven drawers already arranged in fair order. United States.—Forty-six drawers, the arrangement of which has been about half completed. The collection of Paleozoic Shells, &c. from the Western States and of Coal-Plants from Pennsylvania, &c., are of great interest. vill ANNIVERSARY MEETING. West Indies, viz. :—Antigua .... 17 drawers. Jamaica . ee ] Bermudas; 74) Barbadoes .. 4 _ ,, St. Domingo .3402.°\ ,; South Aneried Fae eee al bie as dN) eR RA pe 2 Ne Diop a RTO rae WI CRUGASCOT? SON ete Leas eas AU SEE OUUG, ie ase caters seme s Vm OM arta. ed eel eee eee Van Diemen's LONG a. ec. ASTO chac 56 Little has been done to the latter divisions of the collection beyond placing the drawers in those cabinets in which they are to remain. The collections from Pondicherry and Cutch and part of the West ~ Indian series were found in good order: most of the rest will require much labour upon their arrangement. Besides what have been mentioned above, there still remain a few drawers in the Foreign Museum the contents of which have to be sorted and then worked into their proper places in the cabinets. A very large number of specimens, many of them of great interest, which have long lain unseen in the crypts, will have to be brought into the Foreign Collection upstairs, to which they will form a most valuable addition; and some recent donations (including the rich collection from the Cape of Good Hope, sent by Mr. Atherstone) have to be incorporated. It is not possible at present to form any accurate idea of the space these additions will occupy, but so much room has been made in the Upper Museum by the removal of rock-specimens and the discarding mere rubbish and duplicates, and so much more space may yet be gained by a more thorough weeding of the contents of the drawers, that the Committee have little doubt that the space will be found more than sufficient for the whole of the Foreign Collection at present belonging to the Society. Collections preserved in the Crypts.—Besides what have been al- ready mentioned under the heads of Rocks and Minerals, there still remain downstairs more than 100 boxes of Foreign and British spe- cimens. The Foreign specimens have been roughly examined by the Com- mittee ; many are quite valueless and had better be thrown away ; many are duplicates of specimens upstairs which might be given away : but there are also very many valuable specimens which should be placed in the drawers of the Foreign Collection. It will be a work of considerable labour to separate these, but as it is not possible that this could be done properly while they remained below in the dark, the Committee have had them removed to theroom on the ground-floor, and have commenced a detailed examination of them. They recom- mend that the boxes remain where they are until this examination be completed and their contents finally disposed of. Duplicates.—It has been stated above that the Committee have already set apart a large number of duplicate specimens of Rocks and Minerals which were only an encumbrance to the collection of = ANNUAL REPORT. 1X the Society, but which may be of great value to the Museums of other Institutions. Up to the present time, the Council have only presented a collection of igneous and volcanic rocks to the Museum of Practical Geology, and a set of minerals and of rock-specimens to the Museum of the Queen’s College at Cork: according to the last vote of the Council, the remainder of the duplicates of Rocks and Minerals are now being divided into sets convenient for presentation, which the Committee recommend to be presented to other Institutions mm which they may contribute to the spread of the science. The Committee have not yet made sufficient progress in the ar- rangement of the Foreign Fossils, to propose to the Council any immediate distribution of duplicates of them ; but they hope that the work which they have begun will be pushed forward by the Council, and that all the duplicates both of British and Foreign Fossils may be removed from the collections and from the crypts, and may be dis- tributed where they may conduce to the progress of Geology. The Committee cannot conclude without impressing on the Coun- cil the necessity of authorizing the Curator of the Museum to reject all valueless specimens as they enter the Society’s apartments, either under the control of one of the Secretaries or of a Committee ap- pointed for the purpose. This would be a very slight labour if it were done week by week, and had it been done formerly would have saved half the work of the present Committee. To avoid such labour being again required, it is recommended that as soon as new specimens have been exhibited in the Meeting-room they should be examined, the worthless portion thrown away, the duplicates separated and packed up, and the rest sent at once to the place they are intended to occupy in the collections. Lnbrary. During the past year many unbound volumes have been bound. As the shelves in the Library were overfull, space has been made by removing a number of books to the shelves in the Council-room, se- lecting for removal such periodicals as form long series and are seldom referred to. In accordance with the wish which has been expressed by many of the Members, a copy of the Catalogue has been arranged alphabeti- cally with reference to the shelves occupied by the books, which proves a great assistance to those who make use of the Library. The Committee have every reason to be satisfied with the condi- tion of the Library ; but they hope that the Council will be able to devote a moderate sum to the purchase of new books, and to com- pleting a few works which are now imperfect. Signed, DaNIeL SHARPE. SEARLES Woop. 24th January, 1850. S. P. Pratt per D. SHARPE. Joun Morris. x ANNIVERSARY MEETING. Comparative Statement of the Number of the Society at the close of the years 1848 and 1849. Dec. 31, 1848. Dec. 31, 1849. Compounders:.. ..).2.5: RET fe i ee apeipaee 131 Heesideatg eo occ ee age ieee en ce eee eee 228 Non-residents. . cei. .- << 4- ADT oc sh. aa 456 821 815 Honorary Members...... LD. caeeeeees 19 Foreign Members ...... 30 mere. Personages of Royal Blood 4—73 ........ 4—73 894 888 General Statement explanatory of the Alteration in the Number of Fellows, Honorary Meméers, &c. at the close of the years 1848 and 1849. Number of Compounders, Residents and Non-residents, December 31, 18486 eo. :i4< 1 ek enee =e eee 821 Add, Fellow elected durmg a former]; year, and paid in 1849...... \ ae Fellows elected, and ee eee Residents, 27 1849. Non-residents... 5 838 Deduct, Compounder deceased ..........--...-.. 1 Residents Bin tty Spaae: o ela ce eee 7 Non-tesidents. og) ods 2% wheel eae 6 Resioned. «..ais|.jsacs.cie sla pao: abana eee 8 PROMOVED, 6.6.5.0 Meee ee ee > Total number of Fellows, 3lst Dec. 1849, as above .. 815 Number of Honorary Members, Foreign Members, and Personages of Royal Blood, December 31, 1848. ... 7s Add, Personage of Royal Blood elected in 1849 ...... 1 74 Deduct, Personage of Royal Blood deceased .......... ] Asabove 73 ANNUAL REPORT. Xl _ Number of Fellows liable to Annual Contribution at the close of 1849, with the Alterations during the year. mim per atthe close OF 1S48,. 00.2. 2.0 ae nw ee oo, OO Midd. Pilected and paid in 18497... ook on nis oa we aces 1] Non-residents who became Resident ............ 4 248 Weel WeCCEASEM!. cc. i oes ths blake achat so ace OL POSTE CM ep cea aN ets glial «ions 6 Conmmpounded yy ok wes eke ee sale. 5 + a ] Became Non-resident “on. a cteeheias © sie ses 5 EReIMOVEUN TS ae eae a ie Apert eaee! oe 1 — 20 As above 228 DECEASED FELLOWS. Personage of Royal Blood (1). His Majesty Christian VIII. King of Denmark. Compounder (1). Samuel Turner, Esq. Residents (7). Hon. Charles Ashburnham. Major T. H. S. Clerke. Earl of Auckland. A. L. Gower, Esq. T. W. Beaumont, Esq. R. Heathfield, Esq. Bishop of Norwich. Non-residents (6). Robert Anstice, Esq. S. Hibbert-Ware, M.D. William Bullock, Esq. Right Hon. Maurice Fitz- Frederick Dixon, Esq. gerald, Knight of Kerry. George Silvertop, Esq. Personage of Royal Blood elected a Fellow during the year 1849. His Royal Highness Prince Albert of Saxe Coburg and Gotha, K.G., F.R.S. The following Persons were elected Fellows during the year 1849. March 7th.—Edward C. Ravenshaw, Esq., Conduit Street; and Henry James Slack, Esq., Sion College. 2lst.—James G. Lynde, jun., Esq., Great George Street ; Rear-Admiral Sir Thomas Trowbridge, G.B., Eaton Place; and M. Sylvain Van de Weyer, Portland Place. Xll ANNIVERSARY MEETING. April 4th.—Rev. Ebenezer Prout, Camberwell ; John Bentley, Esq., ‘Portland Place; and Lieut.-Col. William Reid, Baker Street, Portman Square. May 2nd.—Ebenezer Rogers, Esq., Abercarne, Newport ; and Samuel Blackwell, Esq., Dudley. 16th.—Christopher Bagot Lane, Esq., Bennett’s Hill, Bir- mingham. —— 30th.—Peter M. Duncan, M.D., Colchester ; and John Lane Oldham, Esq., Audley End, Essex. November 21st.—Charles Meyer, Esq., Buckingham Palace. December 5th.—Robert A. Slaney, Esg., M.P., Walford Manor, Shrewsbury; Ernest Noel, Esq., Hornsey ; William Lee, Ksq., Gwydyr House, Whitehall; Cornelius Nicholson, Esq., Bernard Street, Russell Square; and Count Achille de Zigno, Padua. The following Donations to the Musrum have been received since the last Anniversary. British Specimens. Ammonites, from the Marlstones, Deddington; presented by C. Faulkner, Esq., F.G.S. Plagiostoma, from the Lias near Adderley, Cheshire, and Bone of Deer from Peat Bog; presented by Richard Corbet, Esq. Specimens of Fossil Fishes from the Mountain Limestone of Armagh ; presented by Captain T. Jones, R.N., M.P., F.G.S. Specimens from the London Clay at Chalk Farm, and from the Gravel- pits of Muswell Hill; presented by N. T. Wetherell, Esq., F.G.S. Fossils from the Silurian rocks of Peeblesshire ; presented by Prof. J. Nicol, F.G.S. Fossils from the Silurian rocks of Ayrshire and Wigtonshire ; pre- sented by J. C. Moore, Esq., Sec.G.S. Slab from the Isle of Arran in the Bay of Galway ; presented by The Very Rev. the Dean of Westminster, F.G.S. Specimens of Plants from the Keuper Sandstone of Longdon, near Tewkesbury, and of a Coral from the Lower Oolite near Chelten- ham; presented by the Rev. P. B. Brodie, F.G.S. Two specimens of Gorgonia Keuperi from the Keuper Sandstone, Leicester ; presented by Prof. Ansted, F.G.S. Foreign Specimens. Impressions of Feet of Birds, Cat, &c., in Red Mud, from the Bay of Fundy ; and Tertiary Fossil Shells from the Island of San Domingo ; presented by Sir Charles Lyell, Pres. G.S. | Shells from the Beds below the Drift at Nantucket, Massachusetts ; presented by Messrs. E. Desor and E. Cabot. Eocene Shells from Clayborne, Alabama, from Mr. Koch’s Collection ; presented by W. J. Hamilton, Esq., Sec. G.S. Specimens of Gold Ore from Brazil; presented by the Rt. Hon. Sir Henry Elhs, F.G.S. ANNUAL REPORT. xii Fossils from the Lignite Formation of the Wetterau and Vogelsgebirge, and specimens of Rocks and Minerals from Germany ; presented by Dr. M. A. Klipstein. Silurian Fossils from Sardinia; presented by Sir R. I. Murchison, V.P.G.S. Fossils from Suez and Aden, and Fishes from Mount Lebanon ; pre- sented by the Rev. Robert Everest, F'.G.S. Specimens of Rocks and Fossils from Western Australia; presented by J. W. Gregory, Esq. Lias and Tertiary Fossils from the Cape of Good Hope (Eastern Province) ; presented by Dr. W. G. Atherstone. Collection of Rocks and Fossils from Hobart Town ; presented by J. E. Bicheno, Esq., F.G.S. Specimens of Fossils from near Fingal, Van Diemen’s Land; pre- sented by Lieut. W. H. Breton, R.N., F.G.S. Rocks and Minerals from the Coast of Greenland and the N.E. Coast of America, collected during the Expedition of Sir John Ross ; presented by the Lords Commissioners of the Admiralty. Cast of Rhinoceros Tooth from Red Crag at Felixstow, Suffolk, and two Casts of Antlers of Deer; presented by Dr. W. B. Clarke. CHARTS AND Maps. The Charts, &c., published by the Admiralty during the year 1848 ; presented by Rear-Admiral Sir Francis Beaufort, by direction of the Lords Commissioners of the Admiralty. Geographical Map of the Globe, and Map of Lower Egypt, Sinai and Arabia Petrzea, by A. Petermann ; presented by the author. Geognostische Karte von Thiringen, von Bernhard Cotta. Sections 1 to 4; presented by the author. Engraving of John Macculloch, M.D.; presented by Mrs. Maccul- loch. Drawings of Fossils from the Crag near Woodbridge ; presented by W. Whincopp, Esq. A Natural Scale of Heights, by the application of which the measures of different countries are reduced to a common measure, constructed by Miss Colthurst (2 copies); presented by G. B. Greenough, Esq., V.P.G.S. The following List contains the Names of all the Persons and Public Bodies from whom Donations to the Library and Museum were received during the past year. Academy of Sciences of Paris. American Association. Admiralty, The Right Hon. the | American Philosophical Society. Commissioners of the. Ansted, Prof. D. T., F.G.S. American Academy of Arts and | Ashmolean Society. Sciences. Athenzeum, Editor of. X1V ANNIVERSARY MEETING. Atherstone, Dr. W. G. Austin, Thos. jun., Esq., F.G.S. Beaufort, Rear-Admiral Sir F., Hon. Mem. G.S. Bellardi, Sig. L. Berwickshire Naturalists’ Club. Bland, T., Esq., F.G.S. Brayley, E. W. jun., Esq., F.G.S. British Association for the Ad- vancement of Science. Brodie, Rev. P. B., F.G.S. Brongniart, Prof. A., For. Mem. G.S. Buch, L. von. pacers James, Esq., F.G.S. Bunbury, C. J. F., For. Sec. G.S. Burmeister, Dr. Hermann. Cabot, M. E. Calcutta Library, Curators of. Carpenter, W. B., M.D., F.G.S. Carter, H. J., Esq. Chemical Society of London. Clarke, Dr. W. B. Corbet, R., Esq. Cotta, Herr Bernhard. Dana, J. D., Esq. Darwin, Charles, Esq., F.G.S. Davis, Captain. Delaunay, M. Dent, E. J., Esq. Desor, M. C. D’Orbigny, M. C. Dublin University Museum. Elie de Beaumont, M. L., For. Mem. G.S. Ellis, Right Hon. Sir Henry, K.C.B., F.G.S. English, H., Esq. Everest, Rev. Robert, F.G.S. Fairbairn, William, Esq. Falconer, Hugh, M.D., Faraday, M., Esq.,D.C.L. F. G.S. Faulkner, C., Esq., F.G.S. Forbes, Prat J. D., F.G.S. Frodsham, Charles, Esq. Garner, Robert, Esq. Geological Society of Dublin. Geological Society of France. Gibbes, R. W., M.D. Goppert, Prof. Gregory, J. W., Esq. Guyot, M. A. Haidinger, Herr W. Hamilton; W. J., Esq., Sec. G.S. Hausmann, Prof. J. F. L., For. Mem. G.S. Heniker, J. S., Esq. Hennessy, Henry, Esq. Hogg, John, Esq. Horticultural Society. Hutton, Captain Thomas, F.G.S. Indian Archipelago Editor of. Journal, Jerwood, James, Esq., F.G.S. Jobert, M. A. C. G. Jones, Captain T., R.N., F.G.S. Klipstem, Dr. Kutorga, Dr. 8. Leeds Philosophical Society. Logan, J. R., Esq., F.G.S. Logan, W. E., Esq., F.G.S. Lubbock, Sir J. W., Bart., F.G.S. Lyell, Sir Charles, Pres. G.S. M Coy, F., Esq. Macculloch, Mrs. Mantell, G. A., LL.D., F.G.S. Moore, J. C., Esq., Sec. G.S. Morris, John, Esq., F.G.S. Murchison, Sir R. I., V.P.G.S. Nattali, M. A. Neuchatel, Société des Sciences Naturelles de. Newbold, Captain. Newcastle on Tyne, Literary and Philosophical Society of. . Nicol, Prof. James, F.G.S. ANNUAL REPORT. XV Northumberland, Natural History Society of. Oldham, Prof. T., F.G.S. Palzeontographical Society. Paris, Muséum d’ Histoire Natu- relle de. Pattison, J. R., Esq., F.G.S. Petermann, A., Esq. Philadelphia, Academy of Natural Sciences. Phillips, John, Esq., F.G.S. Pissis, M. Quetelet, M. A. Ramsay, Prof. A. C., F.G.S. Reeve and Co., Messrs. Reid, Lieut.-Col. William, F.G.S. Rogers, Prof. H. D., For. Mem. G.S. Roux, M. W. Royal Academy of Belgium. Royal Academy of Berlin. Royal Academy of Munich. Royal Academy of Turin. Royal Agricultural Society of mngland. Royal Asiatic Society. Royal Astronomical Society. Royal College of Surgeons. Royal Cornwall Polytechnic So- ciety. Royal Geographical Society. Royal Geological Society of Corn- wall. Royal Institution of Cornwall. Royal Irish Academy. Royal Society of Arts and Sciences of Mauritius. Royal Society of Edinburgh. Royal Society of London. Royal Society of Van Diemen’s Land. Saint-Claire Deville, M. Ch. Sharpe, D., Esq., F.G.S. Silliman, Prof., M.D., For. Mem. G.S. Stevenson, W. F., Esq. St. Petersburg, Imperial Academy of St. Petersburg, Mineralogical So- ciety of. Taylor, R., Esq., F.G.S. Tennant, Prof. J., F.G.S. Tylor, A., Esq., F.G.S. Vaudoise Society. Washington, Smithsonian Insti- tution of. Westminster, The Very Rev. the Dean of, F.G.S. West Riding of Yorkshire, Geo- logical and Polytechnic Society of the. Wetherell, N. T., Esq., F.G.S. Whincopp, W., Esq. Zigno, Count Achille de. Zoological Society. Zurich, Natural History Society of. Last of Papers read since the last Anniversary Meeting, February 16th, 1849. 1849. Feb. 21st.—On the Gypsum of Plaister Cove in the Strait of Canseau, by J. W. Dawson, Esq. ; communicated by the President. On the Tertiary and Recent beds at Nantucket, in Massachusetts, by MM. E. Desor and Ed. C. Cabot ; communi- cated by the President. Notes on some recent Foot-prints on Marl in Nova Scotia, by Sir Charles Lyell, Pres. G.S. xvi ANNIVERSARY MEETING. 1846. March 7th.— On some Fossiliferous beds overlying the Red Crag, at Chillesford, near Orford, Suffolk, by Joseph Prestwich, jun., Esq., F.G.S. -—— On the position im which Fossil Shells occur in the Red Crag, by J. R. Thomson, Esq.; communicated by Prof. Ansted, M.A., F.G.S. March 21st.— Description of Erect Sigillaria with Conical Tap-roots, from the Sydney Coal, Cape Breton, by R. Brown, Esq. ; commu- nicated by the President. Notice of Recent Researches in Asia Minor, by M. P. de Tchihatcheff; communicated by Sir R. I. Murchison, V.P.G:S. April 4th.— On Tylostoma, a proposed genus of Gasteropodous Mol- lusks, bv Daniel Sharpe, Esq., F.G.S. Additional remarks on the Geology of part of Asia Minor, by W. J. Hamilton, Esq., Sec. G.S. April 18th.—Palichthyologie Notes, No. 3.—On the Ganoidei Hete- rocerci of Agassiz, by Sir P. G. Egerton, Bart., M.P., F.G.S. On the Tertiary beds of the Great Glen of Scotland, by the Rev. J. G. Cumming, F.G.S. May 2nd.—On Sigillaria, and some Spores found in its Roots, by E. W. Binney, Esq. ; communicated by the President. On the Microscopic Structure of Nummulites, Orbi- tolites, and Orbitoides, by W. B. Carpenter, M.D., F.G.S. May 16th.— On some Tertiary beds in the Island of San Domingo, by J. C. Moore, Esq., Sec. G.S. —— Observations on the Silurian Strata of the South-East of Scotland, -by James Nicol, Esq., F.G.S. May 30th.— On the Superficial Detritus of the Alps as compared with that of Northern Europe, by Sir R. 1. Murchison, V.P.G-S. June 13th.—On the Valley of the English Channel, by R. A. C. Austen, Esq., F.G.S. Nov. 7th.—On Nerinza, with species found in Portugal, by Daniel Sharpe, Esq., F.G.S. On productive Iron Ore in the Eocene formations of Hampshire, by Alfred Tylor, Esq., F.G.S. On the Sydney Coal-Field, Nova Scotia, by R. Brown, Esq. ; communicated by the President. Nov. 21st.—On a Cutting in the Buckingham Railway, by W. Stowe, Esq. ; communicated by The Very Rev. the Dean of Westminster, BGS: — Se ed —— On the Secondary district of Portugal, by Daniel Sharpe, Esq., F.G.S. Dec. 5th.—On the Age of the Upper Tertiaries in England, by S. V. Wood, Esq., F.G.S. 3 On Mammalian Remains found at Brentford, by John Morris, Esq., F.G.S. Dec. 19th.—On Craters of Denudation and the Structure of Volcanic Cones, by Sir Charles Lyell, Pres. G.S. ANNUAL REPORT. XVil 1850. Jan. 9th.—OQbservations on Dudley Trilobites, by T. W. Fletcher, Esq., F.G.S. Remarks on the Inferior Oolite near Cheltenham, by the Rey. P. B. Brodie, F.G.S. Letter from G. F. Ruxton, Esq., to Prof. Daubeny, M.D., F.G.S., on Voleanic Rocks in Northern Mexico. Letter from Prof, Eugene Sismonda to Sir R. I. Steciicon, V.P.G.S., on the discovery of a nearly perfect Skeleton of Mastodon an gustidens near Asti in Piedmont. Jan. 23rd.—On the Structure of the Deposits between the London Clay and the Chalk. Part I. On the Basement bed of the London Clay, by Joseph Prestwich, jun., Esq., F.G.S. Feb. 6th.—On the Pseudo-Volcanic Rocks of the Papal States and adjacent parts of Italy, by Sir R. I. Murchison, V.P.G:S. After the Reports had been read, it was resolved,— That they be received and entered on the Minutes of the Meeting ; and that such parts of them as the Council shall think fit, be printed and distributed among the Fellows. It was afterwards resolved, — 1. That the thanks of the Society be given to G. B. Greenough, Esq., Leonard Horner, Esq., and Dr. (+. A. Mantell, retiring from the office of Vice-President. 2. That the thanks of the Society be given to J. 8. Bowerbank, Ksq., Dr. W. B. Carpenter, Captain Henry James, Lieut.-Col. Port- lock, and The Very Rev. the Dean of Westminster, retiring from the Council. After the Balloting Glasses had been duly closed, and the lists examined by the Scrutineers, the following gentlemen were declared to have been duly elected the Officers and Council for the ensuing year :— VOL VI. b xvi ANNIVERSARY MEETING. OFFICERS. £4 We 2 CGE, PRESIDENT. Sir Charles Lyell, F.R.S. and L.S. VICE-PRESIDENTS. Sir H. T. De la Beche, F.R.S. and L.S. Prof. E. Forbes, F.R.S. and L.S. D. Sharpe, Esq., F.L.S. Sir R. I. Murchison, G.C.St.8., F.R.S. and LS. SECRETARIES. William John Hamilton, Esq. John Carrick Moore, Esq. FOREIGN SECRETARY. C. J. F. Bunbury, Esq., F.L.S. TREASURER. John Lewis Prevost, Esq. COUNCIL. Rev. P. B. Brodie, M.A. L. L. B. Ibbetson, Esq. C. J. F. Bunbury, Esq., F.L.S. |/Sir Charles Lyell, F.R.S. and L.S. Charles Darwin, Esq., F.R.S. G. A. Mantell, LL.D., F.R.S. and Sir H. T. De la Beche, F.R.S.|| L.S. and L.S. John C. Moore, Esq. Sir P. G. Egerton, Bart., M.P.,/|Sir R. I. Murchison, G.C.St.S., F.R.S. F.R.S. and L.S. Earl of Enniskillen, D.C.L.,F.R.S.|The Right Rev. The Bishop of Prof. E. Forbes, F.R.S. and L.S.|} Oxford, F.R.S. G. B. Greenough, Esq., F.R.S.//Lyon Playfair, M.D. and L.S. Samuel Peace Pratt, Esq., F.R.S. William John Hamilton, Esq. and L.S. William Hopkins, Esq., M.A.,|John Lewis Prevost, Esq. F.R.S. Prof. A. C. Ramsay. Leonard Horner, Esq., F.R.S. L./D. Sharpe, Esq., F.L.S. and E. S. V. Wood, Esq. iasiheniinetatieninpttermt eee] O 6G SSItF a - ae ee eae DOUG 5 ah eee cea ae OSE aun NTO INOARJ UT dDURTeg 9 6 Gh * A [OA ‘euInor uo ‘10[AUT, “Ay “f pue “Y SAssoay\y 07 ang hy ere "SLT "6PST ““aquiavag yste < hjzuadou O GI PElF 9 T oS COP Cor eeecsecnaneevoceenvEe jUnO.Oy JSKIy, ‘s Jayueg ye soured 6) G Il CoP eee eres rereaccoveccevece SPSL jo aouryeq ‘Ysnoudei) “INT ‘dey [Bo1sojoan) Jo yunoooe uo preg 0 a ee eee eee “une “YOIMysarg 9 0 SOF “ITT 0F popreame [epay] wnIpeyyeg Suravisuyq jo 4yson 9 Gg eS COCO EEOC eer eCeecceenscrDecreseeeeeDn o[epsuo'T “M “ITAL 03 plemMy O VG LG Be Cee et Try eles eet: AMATO E Gh aprdoly ‘W 0} plemy 0 1% adoxT pooy jo adeg oy) wo S[ISSOJ JNO SuT][astyd Jo yso0q 2G ee *SINAWAV —_—— “halnspall “LSOAAYd "I'L ‘OS8T ‘OS ‘une O G SCLPF [‘papnjaur asay pou si anhojnjn) havag “YT pun jousmor fpsazuong ‘shuipasoo4g ‘suo “IDSUDA), pjosun fo yao7s ‘aanjrudny ‘AADAQ “PT ‘suorp20n09 pouampy ay) fo angva au “IN| O FI LZ aS Oot. a ee Gre EO SUOTNIIUOD JO sivatry Cee rere creas cer eccerscerereseaces poos po.opris Oe) 9 ‘as ‘6781 0} 101d suoIyNqiIyU0g jo sreal1y O 81 6€ *(poos pasaptsuos) S90] UOISSIUpY JO sieo11y [0 ie 6) O Cay Gee gag Teas STORTO4) 0G ‘SOT 7L6GE ‘Ayrado.1g popun 4 re gf 61 BMLIMCUEUUIOICUOIOUICIOIOO OOOO OOOO OOOO Tacit spury Pp Be) i) ul soured T If LG Deh ee ee re eeu S.Jayueg ul souRle gq O ST ST Seek ee ee ee On dinosg ng 10J ang 0) G Ui ne ae ay aero Og) stoyyny IO} ONG 6 ST OG ‘A ‘OA ‘jeauinor uo “05 pue UBUISUOT ‘sissoq\ WO. ong nas Sue of “ALUTAIOUg d 8fiqaw0g ay2 fo NOLLVO'IV A ‘OS8SI “OE “une ‘sconpnp { YUOTAL GUYATV : ‘AduVHS THINVaG "P2IL109 Wot} PUY pue sjusMII}e4s asoy} YIM sn OF pozuasaid sxoyonoa puv syooq ay} pareduoo DART IAN 9 Tl 18} Oe oz f OF Sil Vale —_—_—_—— POOReCeoor re Oeerorcorecescoeoce *s]U99 jod ¢ "poy ‘PI'ST F801 Jopuny uoreuo0g ayj uo spuapiaicy ACP CULL PO COT eer A ROL Ce Vec Resco VeeeneeDese (pos) de [eo1Sojoar) ay} Jo yunovov uo Ppeatadoxy ORG 9 8 Il pung dep yearSojoar ‘s,1ayueg ye aouRleg 19 0 9 O oan Hn yunossy AreurpigQ 0} SuiSuojag puny woryeuogy uoyse]joAA oy} Uo “6F8t Avenues jo ysT ‘s,1ayueg ye aouejeg ‘SLdIgoay Ries 2h 2p "SINQODOY Lsaut. XxX Income and Expenditure during the INCOME. Outstanding, 1848: £ Quarterly Journal, Vol. IV. eo? Longman & Co. ae paid June 8th. . se 45 ieee S. d. Balance at Banker’s, January 1, 1849.... 483 17 6 Balance Ditto (included in Trust Account) 0 6 O Balance in Clerk’s hands ............-- 27 ole — 5ll Composition received .......---+--+eseee-- ees ee 31 Arrears of Admission Fees ............ 1010 0 _ Arrears of Annual Contributions........ 34 22380 Admission Fees of 1849 .. 325-22. ee oe ee 12) Annual Contributions of 1849... 22... . so. ee Dividends on 8 per cent. Consols........-.---+---+ 108 Sale of (ransactioms | 5.5 sane te ee oes rt 2 Sale of Transactions in separate Memoirs ........-. 2 Sale of Proceedings .........- ++ e+eeee+s se cteees 2 Journal, Vol. I., allowance on sale from the Publisher. . 8) Sicior howl. Weal eS eo ale oe ea 8 Sale of Journal, VoljUl.) >... (ss ..< Shee cee 9 Sale of Journal, VolPV.: 8922) aigie: See. Acc Sale of Journal, VolVe Se 22685 2852). co eee 146 Sale of Library Catalogue,..........++++-++++++>- 0 We have compared the Books and Vouchers presented to us with these Statements, and find them correct. DANIEL SHARPE, S. 11 d. 8 CO = red AWnranoorqoaorcocdco es ee eee ALFRED TYLOR, } Auditors. £1769 13 11 Jan. 20th, 1850. Sa XX1 Year ending December 31st, 1849. EXPENDITURE. Outstanding, 1848: Quarterly Journal, Vol. IV. (Messrs. R. and J. E. Taylor). Quarterly Journal, Vol. IV. (Messrs. Reeve and Co.) .... Warmipocitions myested .. 6...) 6. se eee He i: General Expenditure : EGe og) TPES), Saogd8 deans caadaegneucolacn coc derdocssceuaueacooSce 35 6 INUR®) JWDR IRIN Soagpbooense copoeriedodobbanueconned. bo oO BAGS MENEIIAITS, i racisielale sie iandciieniesicieisiitelels Selenieiee siecle 32 9 HEMI UNE WLEPAINS 0.5. sence mses ceieciscideesenesenisicesne HS 7 INiGiyy LEWIS ATTY) Gon ooasonaeosoocoocinooccobsudenoadacneT ll 0 ING) noha qasecanaesapsdoadene aoanunoop acces sesapooccocaos6 43 8 UTE Na ponpo- an annonelagoDae misc onor cadapon cen se cocdicoer 26 4 Miscellaneous House Expenses, including Post- i 47 92 CEES cit Sage Ee Metab ciaceepnciescinaeo eget MSURULOTTEIN,, hoocennendeneesnae sab aos CoOR Eee aRoLG Cone TA8 Miscellaneous Printing ............56 ScRoanoene cee) OONLO TIGA GE IW IGG) Se Ganiepepeco sas cccssnocurcapnancascn 26 17 ony Set Gs i 48n 4"0 810 5 3110 O cons MOSCaRCAS ———— 292 1 9 Salaries and Wages: Assistant Secretary and Curator ..............+.4 163.6 3 Demeester) eee 2 enn sn as selaielslus els omstenaaineisowss 100 0 0 BERG CL Me ch «Os Selsec while in another direction it is continu- ously superimposed for miles on beds of highly inclined flysch of eocene age*, aspect of a primary rock ;’ * Quart. Journ, of Geol. Soc. vol. v. p. 246. xl PROCEEDINGS OF THE GEOLOGICAL SOCIETY. It seems that in the course of the stupendous movements which have raised these modern beds to the height of 8000 feet above the sea, and caused portions of them to become crystalline or metamor- phic, large masses of the solid Jurassic limestones of the Oxfordian age have been pushed bodily out of their place, and planted uncon- formably on the edges of strata of the nummulitic series. Our in- defatigable colleague naturally shrinks from offermg any explanation of so marvellous and anomalous a state of things, extending as it does over a considerable area. In attempting to estimate such gigantic movements, the powers of imagimation, he says, are at fault; and * surely,’ he adds, ‘‘ it is not unphilosophical to believe that in those days the crust of the earth was affected by forces of infinitely greater intensity than those which now prevail.’ In particular, he regards the apparent inversion of the tertiary molasse along the flanks of the Alps, and its great elevation, as ‘‘a clear demonstration of a sudden operation or catastrophe*.”’ Now, I shall first venture to remark, in regard to these theoretical views, that the Alps, when considered as a mountain-chain which has originated entirely since the commencement of the tertiary period, bear emphatic and irrefragable testimony to the fact, that the inten- sity of the causes which have disturbed the crust of the globe has not diminished in the tertiary as compared to the secondary or pri- mary fossiliferous epochs. It may possibly be still contended, that the energy and violence of the movements were more general in those earlier epochs, supposed by some to have been close upon the con- fines of “ the reign of Chaos and Old Night ;’ but it cannot be pre- tended that there are any proofs of a more magnificent development of the disturbing forces in any given region of equal extent, and ac- complished in an equal lapse of time, at any period antecedent to the upheaval of the Alps. If, however, any one should maintain, that in the earlier ages the movements which upheave, depress and derange the position of strata were more general, and that they agitated simultaneously much wider horizontal areas, it will be easy to adduce the most overpowering evidence to the contrary. The wide extent in the United States of America, and in parts of Russia, of Carboni- ferous, Devonian and Silurian strata, which although upraised above the sea, continue almost as level as when the beds were first thrown * Quart. Journ. of Geol. Soc. vol. v. p. 258. ANNIVERSARY ADDRESS OF THE PRESIDENT. xlin down beneath its waters, clearly demonstrates the limitation of the agency to which great foldings and contortions of stratified rocks have been due to very confined spaces in each epoch. Were it other- wise, the multiplication of such extensive convulsions during a long succession of ages would have made it impossible to find any spot on the globe where the oldest rocks had escaped extreme derangement. It only remains therefore for the advocates of the paroxysmal hypo- thesis to assert that, although the disturbing forces have by no means grown feebler in the modern or tertiary times, as compared to pe- riods when the oldest of the known strata were deposited, yet there have been brief zeras of convulsion on a very grand scale, when the ordinary repose of nature was violently interrupted in particular re- gions (as in the Alps, for example) in a manner wholly different, in regard to the magnitude of the effects produced, from any which we have witnessed in historical times, or which ever occurred formerly during the ordinary and normal state of the globe. That doctrines of this kind are popular, I am well aware; and if you desire to know how many modern writers have declared in their favour, I refer you to the excellent work which has just been pub- lished by one of our foreign members, M. d’Archiac, on ‘The Hi- story of the Progress of Geology from the years 1834 to 1845.’ He has executed conscientiously nearly half of the laborious and delicate task assigned to him by the Geological Society of France, and has given us a faithful digest of memoirs written in a variety of languages and scattered through the Proceedings and Transactions of numerous scientific bodies, or the periodical magazines and journals of almost every civilized country. A geologist of practical experience in the field, as well as of extensive erudition, was required to make a good classification of such complex materials, and justly to appreciate their relative value. In M. d’Archiac’s pages every author of merit has been allowed an impartial hearing, and the expositor’s own occasional criticisms are not obtruded too prominentiv op he reader’s attention ; when they are offered, they are so judicious as to aid us materially in understanding the faithful analysis he has given of the opinions of others. In the concluding part of his chapter on “ Le terrain mo- derne,” and when speaking of active volcanos, and in other places, he stoutly denies the adequacy of the causes which have modified the earth’s crust in historical times to produce effects such as may enable von. vt. ¢ xliv PROCEEDINGS OF THE GEOLOGICAL SOCIETY. us to explain geological monuments. ‘‘ We must have recourse,” he says, ‘‘ to other causes, both organic and inorganic, of a more ener- getic and even paroxysmal character *.” On this subject I must make two preliminary remarks: First, that our present inability to decipher some of the monuments of past ages by a key derived from the effects of causes now acting, ought never to be adduced as an argument of much weight in favour of the paroxysmal theory ; for it might with equal or greater propriety be urged as a reason for believing in the adequacy of existing causes, or their identity with those of former times, since no one doubts that we are ignorant of the nature of many subterranean and suboceanic changes now in progress. If therefore there was nothing obscure or mysterious in geological pheenomena, if they simply presented to us a picture of objects as familiar as the lavas of Vesuvius or the cal- careous tufas of mineral springs, or the newly-formed deposits of a delta seen at low water, we should be entitled to suspect a great want of analogy between the ancient and modern processes at work above and below the earth’s surface. We should then be entitled to ask, where are the nether-formed and deep-sea formations of the olden time? Where are the signs of those changes brought about in the bowels of the earth corresponding to such as are now in progress in regions inaccessible to human observation? Why have not the causes which have upheaved mountains and deeply fissured the rocks, or which have denuded large areas, revealed to us ancient stratified and unstratified rocks, wholly distinct from any which we now see generated by ordinary volcanic action or formed in lakes and shallow seas. Secondly, it should be thoroughly understood that the decision of the question at issue can in nowise be determined by simply com- paring the magnitude of the changes brought about in historical times with those of antecedent periods. It may be safely affirmed, that the quantity of igneous and aqueous action, —of volcanic eruption and denudation, —of subterranean movement and sedimentary depo- sition,—not only of past ages, but of one geological epoch, or even the fraction of an epoch, has exceeded immeasurably all the fluctua- tions of the inorganic world which have been witnessed by man. But we have still to inquire whether the time to which each chapter or page or paragraph of the earth’s autobiography refers, was not equally * Archiac, Hist. des Progrés, &c. tome i. pp. 209, 670. ANNIVERSARY ADDRESS OF THE PRESIDENT. xlv immense when contrasted with a brief zra of 3000 or 5000 years. The real pomt on which the whole controversy turns, is the rela- tive amount of work done by mechanical force in given quantities of time, past and present. Before we can determine the relative in- tensity of the force employed, we must have some fixed standard by which to measure the time expended in its development at two di- stinct periods. Dr. Whewell has justly observed, that “mechanical power retains its amount, however much it be distributed through time and divested of the character of extraordinary violence*,’’—a principle which should never be lost sight of when we contrast the effects of the historical with those of antecedent epochs. It is not the magnitude of the effects, however gigantic their proportions, which can inform us in the slightest degree whether the operation was sudden or gradual, insensible or paroxysmal. It must be shown that a slow process could never in any series of ages give rise to the same results. The advocate of paroxysmal energy might assume an uniform and fixed rate of variation in times past and present for the animate world that is to say, for the dying-out and coming-in of species, and then endeavour to prove that the changes of the inanimate world have not gone on in a corresponding ratio. But the adoption of such a standard of comparison would lead, I suspect, to a theory by no means favourable to the pristine intensity of natural causes. That the present state of the organic world is not stationary can, I think, be fairly inferred from the fact, that some species are known to have become extinct in the course even of the last three centuries, and that the exterminating causes always in activity, both on the land and in the waters, are very numerous; also, because man himself is an extremely modern creation ; and we may therefore reasonably sup- pose that some of the mammalia now contemporary with man, as well as a variety of species of inferior classes, may have been recently introduced into the earth, to supply the places of plants and animals which have from time to time disappeared. But granting that some such secular variation in the zoological and botanical worlds is going on, and is by no means wholly inappreciable to the naturalist, still it is certainly far less manifest than the revolution always in progress in the inorganic world. Every year some volcanic eruptions take * Quart. Journ. Geol. Soc. vol. iii. p. 231. e2 xlvi PROCEEDINGS OF THE GEOLOGICAL SOCIETY. place, and a rude estimate might be made of the number of cubic feet of lava and scorie poured or cast out of various craters. The amount of mud and sand deposited in deltas, and the advance of new land upon the sea, or the annual retreat of wasting sea-cliffs, are changes the minimum amount of which might be roughly estimated. The quantity of land raised above or depressed below the level of the sea might also be computed, and the change arising from such move- ments in a century might be conjectured. Suppose the average rise of the land in some parts of Scandinavia be five feet in a hundred years, the present sea-coast might be uplifted 700 feet im fourteen thousand years; but we should have no reason to anticipate, from any zoological data hitherto acquired, that the molluscous fauna of the northern seas would in that lapse of years undergo any sensible amount of variation. If a botanist were asked how many earth- quakes and volcanic eruptions might be expected, and how much the relative level of land and sea might be altered, or how far the prin- cipal deltas will encroach upon the ocean, or sea-cliffs recede from the present shores, before the species of European forest-trees die out, he would reply that such alterations in the inanimate world might be multiplied indefinitely before he should have reason to anticipate, by reference to any known data, that the existing species of trees in our forests would disappear and give place to others. In a word, the movement of the inorganic world is obvious and palpable, and might be likened to the minute-hand of a clock, the progress of which can be seen and heard, whereas the fiuctuations of the living creation are nearly invisible, and resemble the motion of the hour-hand of a time- piece. It is only by watching it attentively for some time, and com- paring its relative position after an interval, that we can prove the reality of its motion. If therefore in the coal-measures of South Wales or Nova Scotia we find the same fossil trees repeated through a mass of strata formed in shallow water 10,000 feet thick, we ought not to feel surprised, but merely conclude that formerly, as now, the rate of change in the vegetable kingdom was extremely slow, so that a stupendous mass of stratified sand and mud, as well as great revo- lutions in physical geography, might be slowly effected, without there being time for any important fluctuation to be brought about in the species of plants inhabiting the globe. I have endeavoured to show in my ‘Second Visit to the United ANNIVERSARY ADDRESS OF THE PRESIDENT. xiv States *,’ that a great oscillation of level has taken place in the valley of the Mississippi and its tributaries, by means, first, of a slow down- ward movement, and then of an ascending one, and that the whole was accomplished since the period when the freshwater and land- shells now inhabiting that great valley were already in existence. We ought not therefore to be surprised when we discover sea-beaches in Norway 700 feet high, in which the shells are identical with those now inhabiting the German Ocean ; for we have already seen that the rise of land in Scandinavia, however insensible to the inhabitants, is rapid when compared to the rate of contemporaneous change in the testaceous fauna. Were we to wait therefore until the mollusca shall have undergone as much fluctuation as they underwent between the period of the liassic and upper oolite formations, or still more between the oolite and chalk, or between the Wealden and eocene strata, what stupendous revolutions in physical geography ought we not to expect, and how many mountain-chains might not be produced by the repe- tition of shocks of moderate violence, or by movements not even per- ceptible by man! I may take this opportunity of stating, in refer- ence to the permanent effects of subterranean movements in our times, that in all likelihood we are always in danger of underrating their intensity, because we can only measure their amount on the sea-coast, whereas the adjoiing mountain-chains seem generally to be more shaken by earthquakes, and probably undergo a greater change of level than the low countries. Let us now return to the Alps, and inquire whether geologists who ascribe their origin to paroxysmal forces have been able of late years to bring to light any new facts in support of their favourite doctrine. On the contrary, if I mistake not, they have been more and more compelled to assign the time during which the disturbing power was exerted to a succession of distinct geological periods, in some of which the force must have operated very slowly, while in other cases where it was sudden it may probably have been intermittent, and consisted, as in ordinary volcanic action, of a repetition of shocks or explosions of moderate intensity. In illustration of these principles, I may first mention that some of the volcanic eruptions of the Alps, which produced the porphyry called melaphyre, broke out again and & * Vol. iil. chap. xxxiv. xlviil PROCEEDINGS OF THE GEOLOGICAL SOCIETY. again, as M. Favre has demonstrated, in the sea of the Jurassic period, and they were accompanied and followed by metamorphic action, occasioned by gaseous emanations. ‘The tuffs and trap dikes of Monte Bolca and the Vicentine show that other volcanic eruptions poured out lava and ejected scoriz into the waters of the eocene sea. Again, after this period, the protrusion, if not the formation, of the talcose granite, or protogene of the central nucleus of the Alps, oc- curred. The upheaval of nearly the whole mountain mass, from the waters of the eocene sea to an elevation of more than two miles above its level, happened subsequently to the deposition of all the nummulitic beds and the flysch. These latter deposits, thousands of feet in thickness, shared, after the commencement of the tertiary period, in all the movements, whether slow or convulsive, to which the Alpine rocks owe their curvatures, dislocations, and vertical or lateral displacement. The grand sinking-down of the nagelfiue or conglomerate of the molasse, more than a-mile vertically, belongs again to a still later period, which did not begin till all the eocene movements had terminated, and was due to a gradual subsidence along the whole northern flank of the chain. At a still more modern era, the entire upheaval of the same molasse took place, so that it reached at length its present altitude of 3000 or 4000 feet above the sea. Nor did the uplifting agency cease here, for it contmued till the newer or subapennine tertiary beds were made to emerge. There are proofs indeed of the relative level of sea and land having been modified even after the erratic blocks were conveyed to their present sites, or subsequently to the glacial period of Northern Europe. This assignment to a great number of distinct and separate periods of the work done by the moving and disturbing powers, is by no means the result of the study of the Alps exclusively. In other moun- tain-ranges it is now ascertained that the upheaving and depressing forces have been propagated in succession along the same parallel zones of country; and M. Elie de Beaumont has frankly confessed that he was in error when he first pronounced the Pyrenees to be a chain due to a single upthrow, “un seul jet,” or ‘‘une chaine élevée en une seule fois.” He and M. Dufrénoy now go so far as to agree with M. Durocher, that in the Pyrenean chain, in spite of the general unity and simplicity of its structure, six, if not seven systems ANNIVERSARY ADDRESS OF THE PRESIDENT. xlix of dislocation, each chronologically distinct from the other, can be made out*. In regard to the Alps, it appears from the observations of Leo- pold Von Buch, Sir Roderick Murchison, and others, that whatever be the major axis of the crystalline mass in the centre, such also is the prevailing direction of all the sedimentary deposits which lie on either side of the chain. Whether the axis be composed of gra- nite, syenite, gneiss, mica-schist, marble, dolomite, or of any rock formed by eruption or by the metamorphism of pre-existing strata, there is obviously some connection between the position of the cen- tral crystalline nucleus and the dominant strike of the flanking de- posits. It is as if the intrusion of the igneous matter at certain periods had not only raised the chain, but so injected and distended its cen- tral parts, as to force outwards the pliant strata on each side, and to cause them to fold themselves into parallel anticlinal and synclinal flexures. The theory first proposed by Von Buch, of the conversion of mountain masses in the Tyrol and other parts of the Alps ito dolo- mite, and of other limestones into gypsum, has been gradually em- braced by the majority of the most eminent geologists who have carefully examined the great chain. The porous and cavernous nature of the dolomite are referred to by MM. E. de Beaumont and Morlot as a character implying the alteration of a compact rock into one of more open texture which had been permeated by gases}. “ It is now more than twenty years,”’ says De Beaumont, writing in 1847, ‘* since I first advocated Leopold Von Buch’s views, who attributed the gypsums and dolomites of the Alps to épigénie, or to the altera- tions of calcareous masses by mineral springs and gaseous emana- tions which came up from the interior of the earth at the time when the porphyries called melaphyre were formed{. M. Frapolli, in re- ference to similar metamorphic action, has adduced numerous facts illustrative of the manner in which carbonates of lime may have been turned by sulphurous vapours into gypsum; and Sir R. Murchison reminds us that the well-known thermal waters of Aix do now ac- tually change the ordinary Jurassic limestone into sulphate of lime ; - while, according to M. Coquand, another example of the like metamor- * Bulletin, 2nd Series, vol. iv. p. 1368. + Ibid. vol. vi. p. 318. ¥ Ibid. vol. iv. p. 1282. PROCEEDINGS OF THE GEOLOGICAL SOCIETY. phism is afforded by Mofettes, where the sulphuro-hydrous emana- tions turn the cretaceous limestone into gypsum along the lines of fissure which they permeate*. M. Favre, as before stated, has shown that the period when the porphyries called melaphyre were erupted agrees well with this hypothesis, and that the heat and gases disen- gaged during such volcanic outbursts might well have transformed the calcareous into magnesian rocks. Thus it is supposed that the carbonate of lime containing shells of the Jurassic epoch has been slowly transformed into magnesian carbonate, and perhaps an increase of volume was gradually acquired by the gypseous and dolomitic masses in proportion as they derived fresh accessions of mineral matter from below. If so it may have caused expansion, and have furnished an irresistible lateral pressure. If in the central parts of the Alps we suppose heat to have accom- panied the metamorphic action which has converted into gneiss and mica-schist, not only the Jurassic and cretaceous, but even certain eocene strata, this same heat must have caused many kinds of rock to expand, and might, im this manner, slowly give rise to the sideway thrust exhibited in the curved beds on either flank of the cham. It is now known that granite and sandstone, while solid, expand and contract, even under such a range of atmospheric temperature as the difference of a Canadian winter and summer produce. We must also take into account that highly inclined or vertical argillaceous strata, such as the flysch, would shrink when heated, and give off their water ; while other rocks, ranged side by side, might be simul- taneously expanding or partially melting, so as to occupy more room, and that the clays might thus be pressed into solid shales and ac- quire irregular and complicated curves. The irregularity and con- fusion would be greatly increased by local variations in the composi- tion of the stratified deposits, whether in the direction of their strike or dip, and also by the unequal intensity of the heatmg and cooling processes, whether the central be compared with the lateral parts of the chain, or the superficial with the internal parts. Yet we cannot feel sure, that were such mighty changes now in progress In any range of mountains subject to earthquakes, such as the Andes or Himalaya, we could guess at the direction of the movement, for the contraction or expansion of mineral masses might be carried on as * Bulletin, 2nd Series, vol. vi. p. 124. ANNIVERSARY ADDRESS OF THE PRESIDENT. hi slowly as the growth of a tree or the swelling of its roots in the soil. M. de Beaumont, in his essay on volcanic and metalliferous ema- nations*, observes that, according to the experiments of Deville, the contraction of granite in passing from a melted or plastic to a solid state must be more than ten per cent. We have here then at our command an abundant source of depression on a grand scale at every geological period in which granitic rocks have originated. All mine- ralogists seem agreed that the passage from a liquid or pasty to a solid and crystalline state cannot, in such cases, have been instantaneous throughout voluminous masses; yet by suddenly crystallizing alone could it have given rise to the paroxysmal downthrow of overlying rocks. On the contrary, every hypothesis seems to proceed on the assumption that the crystallization of granite was an extremely gra- dual process. Many very instructive speculations on this head will be found in the writings of Scheerer, Frapolli, Fournet, Durocher, De Beaumont, and others, who have attempted to explain the reci- procal penetration of the crystals of quartz and felspar which enter into the composition of granites. These minerals, as is well known, have crystallized im an order independent of their relative fusibility, the quartz not only imprinting its form on the felspar, but some- times itself receiving the imprint of the crystals of felspar. Gaudin and Fournet, in order to account for this fact, have shown that dis- solved flint may cool without solidifying, and remain in a gelatinous state, and thus crystallize after the felspar and mica; while M. de Beaumont has suggested that electric action may prolong the dura- tion of the viscosity of silex +. The conglomerate of the molasse called nagelflue, before alluded to, and referred to the miocene, if not in part at least to a still later (pliocene) date, attams m some places a truly wonderful thickness, exceeding 6000 and even 8000 feet. It is very conspicuous in the Rigi and in the neighbourhood of Lucerne, as well as in the Speer near Wesen. The lower part of the group, containing terrestrial plants, fluviatile shells, and the bones of extinct land-quadrupeds, is considered by M. Escher as a freshwater formation, while some of the sandstones and marls of the upper members of the series contain * Bulletin de la Soc. Géol. 2nd Series, vol. iv. p. 1312. + Bulletin, 2nd Series, vol. iv. p. 1022. hi PROCEEDINGS OF THE GEOLOGICAL SOCIETY. marine shells*. To explain the origin of such a succession of pebbly strata, we are naturally referred, by Studer, Escher, Sir R. Murchison, and others, to a long-continued depression along the whole external northern face of the Alps. Numerous torrents are supposed to have issued from the islands which then occupied the site of the loftiest portions of the chain, and the continuity of the strata is explained by imagining them to have accumulated on a shelving shore like that of the present maritime Alps. At first the materials must have been arranged in beds which sloped away from their parent rocks of the Alps; yet after smking successively to enormous depths, they have been brought up again, so as to dip towards the older rocks, as if they passed under them. The first part of this grand subsidence of the sea-bottom was doubt- less analogous to that now in progress on part of the coast of Green- land. But if the adjoimimg land participated in the same downward movement, it is difficult to conceive how it escaped being submerged, or how it could continue to retain its size and altitude so as to continue to be the source of such an inexhaustible supply of pebbles. Wecan _ scarcely avoid speculating on a contemporaneous slow upheaval of the mountains. There may have been an ascending movement in one re- gion, and a descending one in a contiguous parallel zone of country, as the northern part of Scandinavia is now rising while the southern portion in Scania is sinking, or at least has sunk within the historical period. Perhaps the not uncommon occurrence, of deep sea in the immediate vicinity of bold coasts and mountain-chains, may be con- nected with extensive lines of fault, parallel to the shores, on the op- posite sides of which, vertical movements may be taking place m con- trary directions, or one side may be motionless, while the other is subsiding. In no other way does it seem possible to account for the proximity, throughout a long series of ages, of high land, and of a sea-bottom always going down so gradually as to remain for a long time the receptacle of annual tributes of rolled pebbles, and acquiring in the end a thickness of 5000 and 8000 feet. In regard to faults which have shifted rocks several thousand feet in a vertical direction, it is often too hastily assumed that they must have been produced suddenly ; whereas the reverse is indicated by the fact that the walls of such faults are rubbed, polished and striated, as if they had been * Murchison, ibid. p. 229. ANNIVERSARY ADDRESS OF THE PRESIDENT. hin subjected to friction long continued or many times repeated. The mass moreover of fragmentary matter usually included between the opposite walls of such rents is partly reduced to fine clay or dust, and partly filled with stones which have been superficially scored in various directions. The minute study of the structure and organic contents of strata of various ages, has made us of late years more and more familiar with the hypothesis of a slow sinking of the ancient floor of the ocean going on while it was receiving repeated accessions of sediment. We must not forget that in all such cases a solid foundation of subjacent rock of unknown depth, and perhaps much older than the newly su- perimposed deposit, is undergoing simultaneously a change of posi- tion, and that rocks still lower are undergoing, whether by cooling or crystallizing, a change of structure. These very gradual movements are quite as remarkable in the paleozoic as in the tertiary periods. By consulting the ‘ Memoirs of the Geological Survey of Great Bri- tain,’ you will learn that in Wales, and the contiguous parts of En- gland, a maximum thickness of 32,000 feet (more than six miles), of carboniferous, Devonian and Silurian beds, has been measured, the whole formed whilst the bed of the sea was continuously and tranquilly subsiding. In illustration of a movement of the same kind, I need scarcely remind you of the coal-measures of South Wales, with their numerous under-clays, each containing Stigmaria, a pheenomenon to which Mr. Logan first drew our attention. Mr. Binney of Manchester has smce proved to us that all these Stigmarize, found in the floor of every coal-seam, are the roots in situ of fossil trees, chiefly of the ge- nus Sigillaria, and that they are occasionally attached to their stems or trunks,—a conclusion fully confirmed by the more recent observa- tions of Mr. Richard Brown on the coal-fields of Nova Scotia. Sir Henry De la Beche also, in his paper on the rocks of South Wales and the South-west of England, confirms these statements, and shows that subsidences of vast amount took place slowly during the accumu- lation of the palzeozoic strata, the sea all the while remaining shallow, in spite of a depression of one or two miles. Still later, Professor John Phillips, in the second volume of the same ‘Survey,’ has pointed out analogous phzenomena in the old red sandstone of the Forest of Dean ; and these strata, 7000 feet thick, are described as having been formed in a sea of moderate depth. Fossil corals and shells imbedded liv PROCEEDINGS OF THE GEOLOGICAL SOCIETY. as they grew, or ripple-marked sandstones and sandy or gravelly strata with subordinate diagonal layers, confirm these views. Such moye- ments took place contemporaneously with the growth of organic mat- ter, just as subsidence on a grand scale is now going on over vast areas in the Pacific and Indian Oceans,—a class of facts on which Mr. Darwin has founded his theory of atolls, or the origin of annular coral islands with lagoons. His theory, as you have probably ob- served, has been recently embraced and more fully elucidated by Mr. Dana, in his valuable chapters on the geology of the American Exploring Expedition under Capt. Wilkes. The investigations of Professor Edward Forbes, on the laws go- verning the distribution of marine animal life, at various depths in the Mediterranean, have powerfully aided us in determining the con- ditions under which particular strata were formed, the depth of water being deducible from a careful study of the organic contents of each bed. Availing themselves of this key, Captain Ibbetson and Profes- sor Forbes have shown how the lower cretaceous strata of the Isle of Wight have been deposited on a gradually sinking submarine bottom, while Mr. Prestwich has applied the same method of reasoning, with equal success, to the eocene strata of Alum and Whitecliff Bays in the same island*. In this instance it is remarkable, that after a depres- sion of 1800 feet very slowly effected, there was still contiguous land inhabited by the Palzeothere of Binstead and Hordwell and its contemporaries, as well as a freshwater estuary, implyig that the movements in different parts of that region were either very unequal or opposite, or that they consisted of great oscillations of level. It would be easy to cite a variety of continental authorities in support of the same principle, but enough has been stated to entitle me to ask, whether the subsidence of mountainous masses, lying immediately beneath the floor of the ocean, brought about by such slow degrees, can possibly occur, without causing beneath many of the sunk areas, vast flexures of the strata, which as they sink for miles vertically must occasionally be forced to pack themselves into smaller spaces than those which they previously occupied. If this be true, the contortions and foldings of pliant beds, and the fracture and dislocation of the more unyielding rocks, have frequently been due to movements as gradual as those of various ages to which I have been alluding. * Prestwich, Quart. Journ. Geol. Soc. vol. ii. p. 223. ANNIVERSARY ADDRESS OF THE PRESIDENT. lv The imagination may well recoil from the vain effort of conceiving a succession of years sufficiently vast to allow of the accomplishment of contortions and inversions of stratified masses like those of the higher Alps ; but its powers are equally incapable of comprehending the time required for grinding down the pebbles of a conglomerate 8000 feet in thickness. In this case, however, there is no mode of evading the obvious conclusion, since every pebble tells its own tale. Stupendous as is the aggregate result, there is no escape from the ne- cessity of assuming a lapse of time sufficiently enormous to allow of so tedious an operation. No intervention of a cataclysm or series of paroxysmal waves can avail us; andif the geologist could abridge the period, he would find that far from being a gainer, he had deprived himself of the only means ever yet suggested of explaining another set of geological monuments, relating to what we term denudation. It is not simply by fixed and permanent inequalities of level, in the land and sea, or by the alternation of dry and rainy seasons, or of summer heat and winter’s frost, that the aqueous action of torrents, rivers, breakers, tides and currents acquires a sustained energy, capable of denuding wide areas, but by the gradual elevation or subsidence of con- tinents and islands, occasionally accompanied by many minor oscilla- tions of level. It is by reiterated slight variations in the position of a coast line, by the continual shifting of the points of attack, that every portion of the surface of the land is exposed by turns to denudation, and is prevented from ever settling into a state of equilibrium and cessation from waste. If earthquakes agitate the country from time to time, while it is rising or sinking, so as to block up valleys and cause temporary lakes and fissures, or the fall of river-cliffs and sea- cliffs, the power of aqueous destruction will be still further augmented. In the first volume of the ‘ Memoirs of the Survey of Great Bri- tain,’ Professor Ramsay has shown that the missing beds, removed from the summit of the Mendips, must have been nearly a mile in thickness, and he has pointed out considerable areas in South Wales and some of the adjacent counties of England, where a series of pa- leeozoic strata not less than 11,000 feet in thickness have been stripped off. All these materials have of course been transported to new re- gions ; and when it is shown by observations in the same ‘Survey’ that the palzeozoic strata are from 20,000 to 30,000 feet thick, we have a counterpart of older date of denuding operations on a scale of similar lvi PROCEEDINGS OF THE GEOLOGICAL SOCIETY. grandeur, for what has been carried away or borrowed from one space must always have been given to another. The gain must always have equalled the loss, and sediment deposited in one area must be the mea- sure of the quantity of pre-existing rock cleared away elsewhere. The announcement of this principle may seem, perhaps, like insisting ona truism, but I find it necessary, because in many geological specula- tions I observe it is taken for granted that the external crust of the earth has been always growing thicker, in consequence of the accumu- lation of stratified rocks, as if they (and possibly the contemporaneous rocks of fusion, in progress far below) were not produced at the expense of pre-existing rocks, stratified and unstratified. Whether indeed the trap and granite of successive ages were formed by the melting of matter previously solidified, will be questioned by those who contend that the globe was originally a fused mass, and who also assume (still more gratuitously as appears to me) that geological monuments have reference to the period when the melted nucleus was passing to a more and more solid state. But even those geolo- gists must admit that strata of the old red sandstone, or of any other ancient or modern rock of mechanical origin, imply the transporta- tion from some other region, whether contiguous or remote, of an equal amount of solid material, so that the stony exterior of the planet has always grown thinner in one place whenever by acces- sions of new strata it has acquired density in another. The vacant space left by the missing rocks, after extensive denudation, may be less imposing to the imagination than a vast thiekness of conglo- merate or sandstone, or the bodily presence as it were of a mountain- chain, with all its inclined and curved strata; but the denuded tracts speak a clear and emphatic language to our reason, and like mountain masses of fossil nummulites, or of corals and shells, or seams of coal based on under-clays full of Stigmaria and surmounted by erect fossil trees, demand countless ages for their origin, and these ages supply the time in which continents and mountain-chains may rise and sink, without sudden, instantaneous or paroxysmal action. I have already alluded to the slow crystallization and consequent contraction of granitic mixtures, and to the expansion of solid rocks by heat, and to the melting of stony masses, together with various metamorphic agencies, as the causes of slow and gradual movement, both vertical and horizontal. Formerly, when the stratified materials ANNIVERSARY ADDRESS OF THE PRESIDENT. lvii of the Alps presented to the eye of every observer a confused heap of ruin, before any general laws governing the lines of longitudinal frac- ture, or the parallel foldings of the strata, were caught sight of, it might be argued, that such chaotic disorder implied one or more paroxysmal outbursts of subterranean force, wholly different from ordinary volcanic or any other known agency. But Sir Roderick Murchison agrees with an eminent foreign member of this Society, Professor H. D. Rogers of the United States, and with several Swiss geologists of distinction, that the dislocations and lateral movements of Alpine strata have been obviously regulated by general movements, in which system and law can be discovered. Mr. Rogers, you will remember, declared in this room, when describing the structure of the Alps and Jura, that he recognized a striking analogy between the form of the flexures discernible in these Kuropean chains and those ob- served by him and his brother in the Appalachians of North America. In both cases the successive parallel folds have on one side a steep, short dip, while the other side of the anticlinal flexure is longer and less inclined. This longer side, in the Appalachians or Alleghanies, dips towards the belt of intrusive volcanic rocks on the south-east flank of the cham. So in the Alps, the steep, short dips do not face the crystalline nucleus, but the longer and less inclined ones, except where a curve has been so great that the whole are made to dip one way, the more steeply inclined side having become as it were more than vertical. In the Alps, the anticlinal folds, where they are greatest, dip in- wardly towards the central peaks, and therefore in opposite direc- tions on each flank of the cham. In the Jura, the steep, sharp dips of each parallel fold are upon the side, facing the Alps, and hence Professor Rogers imagines that the subterranean undulations in the earth’s crust, which, according to his theory, gave rise to these flex- ures, were propagated, not from the Alps, but from the district of the Vosges, or the country towards the north-west. To this theory Professor A. Guyot strongly objects, arguing that it is more proba- ble, on the contrary, that the immediate cause of the uplifting of the Jura is to be sought in the upheaval of the Alps. ‘‘ The elevation,” he remarks, ‘‘ of the anticlinal ridges of the Jura dimimishes gradually and regularly in proportion as the Jura recedes from the Alps, the summits sinking from 5000 to 2000 feet. The minor chains also of lviii PROCEEDINGS OF THE GEOLOGICAL SOCIETY. which the system of the Jura is composed are not exactly in the di- rection of the system itself, but oblique in such a manner as to be parallel with the chain of the Alps.’ There is in fact an intimate relation between the two chains, and M. Guyot conceives that the movement has been the result of a contraction of the terrestrial sur- face in consequence of gradual cooling, and that the folding has been due to lateral pressure resulting from this contraction. It is not my purpose to enlarge at present on the rival theories thus brought forward to solve a most difficult problem ; and I con- fess myself unable at present to understand how, according to the hypothesis of Mr. Rogers, the grand flexures of the strata in moun- tain-chains can bear any intimate relation to great waves propagated through a subjacent reservoir of fluid matter. But if M. Guyot be correct in contending that a smking-down of strata by gravity, owing to a slow contraction of part of the earth’s crust below, can explain the fiexures, we have then a cause introduced which might act as in- sensibly as the failure of support, so often witnessed in mines, espe- cially after the removal of seams of coal. Such failure gives rise to what the miners call “creeps,” which clearly prove that the sharpest bends and curvatures of yielding strata may be brought about by im- perceptible degrees. Even if such an hypothesis be entitled, on pure mechanical principles, to equal favour, it should be preferred to one which appeals to extraordinary violence, for it must then be admitted that the “ dignus vindice nodus”’ has not yet occurred. I have already suggested that the talcose or protogene granites of the Alps may belong to the tertiary period. M. de Beaumont be- lieves that they were not protruded into the atmosphere till they had already reached the region of perpetual snow. Whether there may be good grounds for such an opinion or not, it does not appear to me to follow that such granites may not have been solidified at a consi- derable depth in the bowels of the earth. No sufficient reason seems to have been advanced to prove that they ought to be regarded, as the French geologist seems to infer, almost as superficial products*. The limestones, sandstones and shales of the nummulitic and flysch series are of such enormous thickness, that tertiary granites may well be supposed to have crystallized beneath them, and then to have been exposed to view by breaking forth or bursting through * Bulletin, 2nd Series, vol. iv. p. 1299. ANNIVERSARY ADDRESS OF THE PRESIDENT. lix the covering of sedimentary matter in the course of the enormous change of position which the Alpme eocene rocks have undergone. The question is one of the highest importance, because the French academician contends, that all the granites erupted in the earlier pe- riods of the earth’s history differed from those of later date, in bemg much more quartziferous ; and he controverts the doctrine proposed by me in my ‘ Elements of Geology,’ that the difference of mineral composition in the oldest rocks of this class now visible may reason- ably and naturally be explained by imagining them to have originated at a great depth below the surface. On the contrary, M. de Beau- mont supposes that granitic rocks charged with an excess of siliceous acid were formed at the surface in the older times, and he has even had the courage to present us with a diagram of Chaos, entitled “‘Chaos primitif,” representmg a scene by no means rude and dis- orderly, but where we behold two pyramidal mountains, from one of which the ordinary volcanic lavas and more volatile substances, such as sulphur, chlorme and aqueous vapour, are evolved ; while from the summit of the other, granitic compounds, tin, fluor, and the more refractory and less volatile materials; are discharged*. It is sug- gested that the greater part of the metals which usually accompany tin were concentrated in the first envelope of the globe, but after the paleeozoic epoch they were withdrawn from circulation, and like the primitive granites ceased to be emitted from the interior. The gases and vapours, from which the more ancient metalliferous compounds were sublimed, would, it is said, have been most deleterious to or- ganic beings living in the air and ocean, so that their evolution in the sea and atmosphere in later times was discontinued. For my own part, after having given the most patient considera- tion to these views, I see no sufficient grounds for believing that the same granitiform mixtures and metalliferous emanations may not have been disengaged in equal quantity at every successive geological period down to the most modern. We are taught by the activity of several hundred volcanos, that there must now be lakes and seas of melted matter in the interior of the earth, in every state, from one of perfect fusion to one of incipient crystallization ; and as solid rock must thus frequently originate in great masses, under conditions dif- ferent from that of lava poured out into the atmosphere, why should * Bulletin, 2nd Series, vol. iv. p. 1322. VOL. VI. 5 lx PROCEEDINGS OF THE GEOLOGICAL SOCIETY. we not adopt as the most probable conjecture the idea that this mat- ter is now, as of old, passing into granite, or into some of the grani- tiform compounds, more especially when we know that silex abounds in many modern lavas, and that certain obsidians and pumice do not differ materially in their component elements from granite. I fully assent to the doctrine so ably advocated by M. E. de Beaumont, that a large class of metalliferous veins may simply be regarded as extinct mineral springs. They are fissures im which va- pours, or thermal waters eed with various elementary bodies, — have precipitated the materials of a refractory kind, or those which are the least easily retained in solution. The marked agreement be- tween the contents of mineral springs and the emanations from acti 2 voleanos strongly supports this view. But why should we doubt th t fissures now existing in solid rocks may in like manner communicate at one extremity with subterranean masses of fused matter, while at their upper end they terminate in mineral springs? and if so, wl may not hot steam and gases and mineral waters be depositing at this moment, as actively as ever, that class of elementary bodie 125 J8, Gils Wis Oa, Wo Goo Portlocki, Hgert........... Geol. Journ. vol. vi. p. 2. UHRA, ZIG. oo eoaoogae as IP, IBS VOlle Unies WO) eo ac SMES, Be sodgcosuoone J Ve Th Wi@lle THs OS Wiles og EvurRYNoOTUS, Ag. f (CREWMALUS PAR creer eet ere PEK evils dt, pen l54y.y-1.<1- ohael aya AUIS, Us Fea ena ao eaeOD TRA TS, WO ils Oo WEY acon PALHONISCUS, Ag. DES AOEL 74lon TA ago neome or iP IB SMH the joe BY) on oc arcuatus, Higert. .......... Geol. Journ. vol. vi. p. 7 Beaumonti, Ag. Geol. Journ. Uslannyille VAC cn --)-. - <= 1Be 106 Olle Wo joe ks} Sn ge CANAIMATUS PAG eee aes = 21-17 Pie. Vol. i. ps L045). - ALO PLERUS eA ne a eralle/o! case) 1s Geol. Journ. vol. vi. p.4 COMMITS Aen son goed dso P, F. vol. ii. p. 97...» decorus, Weert: 2.0.05... Geol. Journ. vol. vi. p. 7 PUIVETHOVA AS niles ae ales se P. F. vol. tl. p.45.... « PF CLUOMU eA On aii nresic ve o.c1s 2 Geol. Journ. vol. vi. p. 5 CLEC AMS SEAL Wa te. ls -is < «10 P. F, vol. 11. p. 95 ..... Freieslebeni, Ag..........- 125 1G NOG Hs 105 OO) Sonat Grellberbie Golde Ven ccc a. Beitrage ............. Palalp lyase A Pearce ile epee 6:- « P. F. vol. 1. p. 98 ...... eyoiChiinns. Ee oaaopanoode P. F, vol. ii. p. 64 ..... HOM PIS SIMTAS SA G75) 4). eles e+ «> P, F, vol. ii. p. 100..... macropomus, Ag........... P. F, vol. il. p. 81 ..... macrophthalmus, Ag....... P. F. vol. i, p. 99 ..... RIS, AWE SS Go oopouoGeue ean eOle Mpa 7 oe ries megacephalus, Germ.....«. Kuirze «0-6. ee eee eee TONTAUURDIS., Aoo5 doo amneiuIoo ae P. EF: vol. u. p.47 .... Monensis, Figert........... Geol. Journ. vol. vi. p. 5 .. Coal shale Hsperstadt, Thuringia. Saarbriick and Lebach. Saarbriiek and Lebach. Saarbriick and Lebach. Lebach and Boérschweiler. Coal formation . Coal formation . Coal formation . Coal formation ...... Newhaven. Coal formation. ss. Moyola, Moyheeland and Maghera. . Coal formation ...... Newhaven. . Coal formation ...... Newhaven. . Coal limestone Burdie House, sere we . Coal formation ...... Newhaven. niCoalushalemeermacacc Autun. ee Coalshale nerves er Goldlauter. sec Coalyshraleyenien serio Autun. enc Oalushal Glan atisina: bie Autun. .. Coal-measures...... Newhaven, Permianeeneereriee ce Rhone Hill. . Magnesian limestone.East Thickley, &c. Pe OOnlushallematetere crete= Auvergne. Coal shale Munster-Appel. North Stafford. . Magnesian limestone.East Thickiey, &c. . Kupferschiefer Mansfeld, Richelsdorf. . Coal formation Heimkirchen. Magnesian limestone.East Thickley, &c. . Permian Scharfeneck, Ottendorf. . Magnesian limestone. Ferry Hill, Whitley. . Zechstein Ilmenau. . Magnesian limestone.East Thickley, &c. ee ee ee i ay . Kupferschiefer ...... Mansfeld. piMupterschieteri..).\- Mansfeld. yaCoalushale Merve ie. Munster-Appel. 30 COM SNES onteis o5 oe Anglesea, * Gyrolepis giganteus is an Holoptychius, Poiss. Foss. vol. ii. part 2. p. 285. + Portlock, Geol. Mem. p. 469. 10 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [April 18, Summary of Genera and Species (continued). PALZONISCUS, Ag. ornatissimus, Ag........... BP) Be vol. 31.0). 92) annie Coal limestone ...... ornatus, Munster =. os.2<'- 2 se coe vie Oe ee ne ee eee Kupferschiefer ...... pygmeus, H.vow Meyer 3.2% asa. 2 ee eee eee ne Kupferschiefer...... Robisoni, Hibbert ........ Volo ai. p-.98) jee Coal limestone ...... speciosus, Minster 30. 0S Fence ene ee emer Kupferschiefer...... Striolatus.-A ge ne see rosie PB. El yolaap.. Gl ees. Coal limestone ...... Rehebkinisshrseh-.— esis a6 2 Bull. Nat. de Moscou.... Permian............ Moltzn, ies no: eas i PB. Eo yel.ai.psi55, << sec Coalishaler: s ceding whorl, was first stated, 1 believe, by M. D’Orbigny (Annales des Sciences Naturelles, 1826, tome vii. p. 295). This aperture, which was correctly figured—-I believe for the first time—by Mr. Sowerby (Mineral Conchology, vol. vi. p. 73. tab. 538), is best brought ito view by fracturing a Nummulite in a direction perpen- dicular to that of the preceding sections, so as to present a broken edge, of which about one-half is shown in fig. 4. On looking inte the chambers which are thus laid open, along the line aa’, we are of course stopped by the septa 0, 6, each of which is seen to present an aperture c, c, where it abuts against the margin of the preceding whorl. From the examination of specimens fractured in various di- rections, I am quite satisfied that these perforations pass through both layers of each septum, so as-to establish a free communication be- tween one chamber and another. The case is different, however, with regard to certain more minute apertures, (not discerned, I be- lieve, by any previous observer,) which may be seen, by a careful examination under a sufficient magnifying power, to exist on the sur- face of every septum, though not constant either in number or position (see fig. 7, a). I at first believed that these also pass from chamber to chamber; but I am now satisfied that they penetrate that layer only of the septum, on whose surface they open, and that they really establish a communication between each chamber and the adjommg interseptal spaces. Other apertures of the same kind may be gene- rally traced, on careful examination, in those walls of the chambers that form the surface of the whorl; and these, too, appear to com- municate with the interseptal spaces, by channels burrowed in those walls, as shown in the lower part of fig. 6, and also in fig. 16, m which last they are represented as seen in a thin section of the roof of the chambers. Thus the cavity of each chamber communicates with that of the one before and behind it in the same whorl, by the large aperture first mentioned, which frequently appears as if made up by the coa- lescence of a number of smaller perforations (fig. 7, 6), suggesting the idea that the animal substance which originally passed through it was not a single large canal, but was composed of a bundle of mi- nuter tubes or threads. This idea is confirmed by the circumstance, that the outer margin of the included whorl (fig. 7, ¢) frequently presents a series of furrows, corresponding to the notches at the inner edge of the septum (0). Each cavity also communicates freely with the mterseptal spaces on either side, by the smaller apertures and passages last described ; and from this space, as we shall pre- sently see, there was a free passage to the external surface of the shell. The texture of the shell itself differs remarkably from that of any of the Mollusca with which I am acquainted, approaching that which I have described in the common Crab (Reports of the British Asso- ciation, 1847, p. 129). It is everywhere perforated by a series of tubes of extreme minuteness, which pass directly from one surface to the other, their openings being plainly visible on each (fig. 16). The diameter of these tubes is about 1-7500th of an inch ; and their 1849.] CARPENTER ON THE STRUCTURE OF NUMMULINA. 25 distance from each other about 1-15,000th. In a thin vertical sec- tion of the shell (fig. 15) they are seen to run parallel to each other, and to be free from sinuosities or interruptions. The whole of this portion of the shell, therefore, is minutely porous. The structure im question can seldom be clearly distinguished in those Nummulites which have had their texture altered by calcareous or siliceous infil- tration; but as the appearances which these present correspond closely with those exhibited by specimens of VV. /evigata which have been subjected to the same change, I have no doubt that the tubular structure in question is common to the whole group. Very fre- quently the metamorphosis is such as to give the appearance of a minute prismatic arrangement to the shell-substance (as shown trans- versely in fig. 12, 6, 6), by which I was myself deceived until I had examined specimens in which less alteration had taken place. All the Nummulites which I have examined present a remarkable de- parture from this structure, in that portion of the shell which forms the margin of each whorl. Here, instead of an assemblage of minute, closely-set, parallel tubuli, we have a much coarser arrangement, the solid substance being perforated with a smaller number of tubes of two or three times the diameter of those last mentioned, which pass in a radiating manner from the inner to the outer surface. Some indications of this difference are seen in fig. 4 ; but it is much more clearly displayed at 6, 6, fig. 15, which represents a portion of a very thin section taken in the same direction, and viewed by transmitted light. ‘The openings of these tubes on the outer margin of the whorl are not readily discernible, partly in consequence of the somewhat oblique direction of the orifices, and partly through these being usually covered with a calcareous incrustation. When this has been removed by the application of dilute acid, they are easily seen when properly looked for, as was first pointed out to me by Mr. J. Morris. Each successive whorl of the Nummulite, as is well known, not merely surrounds the preceding whorl, but completely mvests it ; so that, in a vertical section, each chamber of the medial plane is seen to be covered with as many layers of shell above and below its own roof and floor, as there are chambers intervening between it and the nearest margin of the section. Thus im fig. 4, the chamber d has three chambers on its exterior, and is invested by three layers of shell above and below, in addition to those by which it is itself inclosed. On the other hand, the chamber e, which is the tenth from the mar- gin,—that is, which has nine whorls on its exterior,—is invested by nine layers above and below. In some species of Nummulites, as the NN. complanata, these investmg layers are closely applied to each other, over the whole of each surface ; the chambers only occupying the margin of the whorl, as shown in fig. 17. But in by far the greater number of species, these successive layers are not in contact with each other, being separated by prolongations of the marginal chambers, which extend over the entire surface of the disk. These chambers are still divided by prolongations of the marginal septa, which are continued between the investing portions of the contiguous whorls, and form a series of vertical partitions, upon which the successive 26 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 2, layers rest. This is shown in fig. 4; in which we see at f, f, f, the three outer investing layers; at g, g, the two spaces intervening be- tween them, which are prolonged from the marginal chambers ; ~ and at h, h, h, the vertical partitions, prolonged from the marginal septa, by which these successive layers are supported one upon another. In general these partitions tend with greater or less regularity towards the centre of the disk; but this is “not the case in N. levigata, for here they run a sinuous and inconstant course, sometimes imoscula- ting, and again diverging, so as to divide the whole surface of the disk into a number of irregular areze. The origin of these partitions from the septa of the marginal chambers, and the character of their subsequent course, are seen in fig. 3; at the left hand are shown portions of three whorls which are laid open through the medial plane; whilst on the right are seen the mvesting portions of two of these, with the broken edges of the partitions formed by prolonga- tions of the marginal septa. A larger portion of one whorl, showing the continuity of the septa and chambers in its marginal and invest- ing portions, is shown in fig. 6. As the course of these partitions is a very strongly-marked feature in the structure of Nummulites, and presents many very obvious differences, | am inclmed to think that from such differences valuable specific characters may be obtaimed. I have now to describe one of the most curious, and until recently unsuspected features in the structure of Nummulites;—I allude to the existence of a series of perforations of considerable size, which pass directly downwards from the exterior, through the superposed in- vesting layers of the successive whorls, however numerous, until they reach the roof and floor of the chambers of the central plane, which they do zot penetrate. Various observers had remarked punctations on the surface of certain species of Nummulites: these bemg some- times elevations and sometimes depressions. I believe that MM. Joly and Leymerie were the first to surmise that these punctations are in reality the mouths of passages, which are blocked up by the infiltration of mineral matter subsequently to the death of the animal, and that their occasional projection from the surface is to be attri- buted merely to the superior hardness of the matter that fills them (which forms the ‘columns’ or pillars of Mr. Sowerby, Joc. eit.), and to the slight abrasion of the shell around them. Guided by the analogous characters presented by the indubitable perforations in the shells of fossil Terebratulze, I had myself arrived at the same conclu- sion, before I became acquainted with the researches of MM. Jol and Leymerie; havmg found that the substance with which these perforations and passages are filled, evidently differs altogether from the texture of the shell itself, and presents all the characters of a calcareous infiltration. In fig. 1 is represented a thin section taken nearly parallel to the surface, so as to pass nearly in the plane of some of the investing layers; the dark portion represents the shelly texture already described ; the irregular light spaces on the middle and left of the figure, are the lacunze filled with caleareous infiltra- tion; whilst at the right, some of the chambers of the medial plane are laid open. These passages may be frequently seen, in a piece like 1849.| CARPENTER ON THE STRUCTURE OF NUMMULINA. 27 fig. 8 obtained by a vertical fracture, passing from the outer surfaces towards the medial plane, in a somewhat conical form, contracting as they descend; but they are never directly traceable into the chambers of the central plane. MM. Joly and Leymerie do not ap- pear to have determined their mode of connection with these cham- bers; although in their ideal figure of the animal of Nummulite (fig. 5), they represent pseudopodia passing out, it must be sup- posed, through such apertures. I have satisfied myself, however, by a careful examination of numerous specimens, that they always ter- minate over the septa (as shown in fig. 8), and actually pass into the interseptal spaces, which we have already seen to have numerous communications with the chambers themselves. I am confirmed in this view, by finding that wherever they penetrate the investing layer of any whorl, the perforations pass between the two laminz of the prolongations of the septa, which are double along their whole course (as may be seen in fig. 6). These laminze diverge to give them pass- age (a, a), and then reunite, thus completely enclosing them, and cutting them off from the vacant spaces between the investing whorls. Thus a direct and continuous tubular connection is formed between the interseptal spaces of the central plane, and the external surface of the shell; and as these spaces are connected, by numerous small apertures in the septa, with the chambers between which they are interposed, we see that no chamber, however deeply buried beneath the investing whorls, is cut off from communication with the medium inhabited by the animal. Inthe Nwmmulina complanata (fig. 17) and other species, in which every investing whorl is in contact with the one it incloses, except at its edge, the perforations have the form of fissures, that correspond with the subjacent septa, towards which they directly pass. These fissures are usually found to be filled with opake matter; and the dark bands thus formed in a transparent section (fig. 12, a, a) are seen to be crossed by delicate white lines, which seem to indicate a division of the fissure into a number of tubes of irregular form,—probably for the passage of pseudopodia. All my observations tend, therefore, to confirm the opinion gene- rally entertained, that the Nummulites are members of the group of Foraminifera; and that each chamber may have been tenanted at the same time by a livmg segment, connected with those before and behind it by means of one or more tubular prolongations, and ab- sorbing its nourishment from without by means of filamentous pseu- dopodia projecting through the system of passages leading fronr the medial plane to the external surface. Every whorl, as we have seen, retains its connection with the exterior by means of the vertical pass- ages; and as we do not find those of the inner whorls blocked up by the investing layers of the outer, but as, on the contrary, they are invariably continued through them, the inference appears to be justi- fied, that the segments of the animal inhabiting the chambers of the inner whorls did uot lose their vitality when thus more deeply inclosed. It will obviously be only from the outer whorl, however, that the marginal pseudopodia can issue; and this would give to those seg- ments an advantage which we may not unreasonably suppose them 28 PROCEEDINGS OF THE GEOLOGICAL sociETy. [May 2, to have possessed, as it is by their agency that the growth of the shell is continued by the addition of new whorls. There is a very striking conformity between the structure of the shell of Nummulites and that of Polystomella crispa, of which an elaborate description has recently been given by my friend Mr. W. C. Williamson (Transactions of the Microscopical Society, vol. ii. p. 159 et seq.). 1 would especially call attention to the following points of correspondence. Mr. W. states that, after a variety of examina- tions, he has satisfied himself “‘ that each septum separating two cells, consists of a double calcareous layer, the soft inhabitant of each. shell secreting its own share.’’ He has noticed, like myself, irregu- larities in the growth of the shell, which are totally inconsistent with the idea of its having been formed by a single body in contimuous growth, like that of the testaceous Cephalopoda. ‘‘ Sometimes,”’ he says, ‘‘ the cells continue gradually to increase in size with symme- trical uniformity, when suddenly one of them is found to be arrested in its development, not attaining to half its proper dimensions; and the new ones subsequently added, are regulated in their increase of size, not by those which had previously attained to their full develop- ment, but by the one which has been so stunted, from the contracted form of which, the cells again continue to grow and increase in regu- lar order; only being thrown back, as regards their size, by almost an entire convolution.”? Of the contained animal itself, which he obtained by dissolving away the calcareous matter of the shell with dilute acid, Mr. Williamson says, that it consisted ‘‘ of a very thin external membrane filled with gelatinous matter.” ‘No trace of minute internal organization, such as a specially located intestimal canal, or ovaries, could be detected” by Mr. W.; nor was he able in any instance ‘to discover with certainty the presence of any foreign bedies in their interior.”” The several segments are described by him as connected by a series of prolongations, which pass through the septa near their inner margms. The segments at first formed have only single connecting necks; but the number of these soon increases, and the outer segments are connected by ten or more such necks, which pass through as many distinct orifices in the septa. If all these orifices were brought together on the central plane, so as to coalesce into one, they would exactly correspond with the single per- forations in the septa of Nummulites. The animal of Polystomella is considered by Mr. Williamson to derive its nutriment from pseu- dopodia, which are projected through numerous minute apertures over the whole surface of the shell. He has not clearly traced these pseudopodia, however, into connection with the segments occupying the interior whorls, which, like those of Nummulites, are mvested by those of later formation ; but he mentions (as Ehrenberg had done), that near the umbilicus they are projected in fasciculi; and he states that the surface of the central calcareous nucleus (which is formed by a thickening of the walls of the smallest cells) is pitted by small but deep depressions, which may be designed to facilitate the exit of the pseudopodia from the innermost convolutions. Mr. Williamson goes on to point out, that to these pseudopodia must be attributed 1849.] CARPENTER ON THE STRUCTURE OF NUMMULINA. 29 the deposition of new matter upon that portion of the central nucleus which is not covered by the investing whorls; and in this view he is in accordance with M. D’Orbigny, who, in his recent work ‘ Sur les Foraminiféres Fossiles du Bassin Tertiaire de Vienne,’ fully recog- nizes the power of the pseudopodia to secrete the calcareous cover- ing. I may remark, that I cannot see how the imvesting layers covering the disk of Nummulites complanata, and the other species of the same group, can be formed in any other way ; since, in these, the chambers are only marginal, the segments of the animal not ex- tending over the disk; and we have no reason to believe in the existence of any external mantle, spreading over the whole surface, whereby these investing layers could be formed. It is worthy of remark, that, in the outer whorls, the two laminee of the septa diverge from each other, asin Nummulites, where they join the outer margin of the chamber; and that they thus leave an inter- septal space, towards which certain prolongations of the animal struc- ture appear to pass. If it should be found that the pseudopodia arise from these, the resemblance of the animal of Polystomella crispa to that by which the shell of Nummulite was probably formed, would seem to be very close. The view which we take of the individuality of the segments of the animal of Nummulite, must depend upon the ideas we entertain regarding the nature of similar aggregations in other Foraminifera, as well as in Zoophytes and the inferior Mollusca. The several segments appear to be, in all essential particulars, mere repetitions of each other; they are formed by successive gemmation from a single pri- mordial segment; and when this gemmation has taken place, the newly-formed segment appears to be as independent of the rest, as are the several polypes in a polypidom. ‘There is no indication that the inner and earlier segments derive their nourishment through their connection with the outer and last-formed; on the contrary, there is every indication that the former continue to maintain the same communication with the exterior which they ever had; and that the necks which are prolonged through the apertures in the septa are rather to be considered in the light of stolons or creeping stems, from which new gemmee are to be produced, than as re- sembling an intestinal canal common to the whole series of segments. We may consider the entire structure, then, either in the light of a series of distinct individuals developed by gemmation from the first- formed segment, like the clusters of the compound Tunicata; or as a single aggregate being, made up of an assemblage of similar parts indefinitely repeated. It does not seem to me of much consequence to decide between these two views, if we distinctly recognize the essential independence of the segments, and their multiplication by gemmation. This is a matter of some importance in regard to the determination of species; for if we are to consider Nummulites as analogous rather to the polypidoms of Zoophytes or Bryozoa, than to the shells of the Mollusca, it is obvious that we must allow for a considerable amount of variation in their form, without any trans- gression of specific limits. It is well known that many species and 30 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 2, even genera of corals have been founded upon variations in the mode of growth in one and the same species; and I am disposed to believe that the range of variation is almost equally great in some species of Nummulites. I have carefully examimed many individuals differing widely in external form, without being able to detect in them any difference in internal structure at all worthy of bemg accounted a specific character ; and this will not be deemed surprising after what I have already stated, respecting the irregularities which may occur in the consecutive chambers of a single whorl. Differences in the proportion between the diameter and thickness of the disk, appear to me to be especially unsatisfactory as specific characters; for I have met with specimens almost lenticular, which could not be dis- criminated by any other indications from specimens of a nearly glo- bular form. It is obvious that such differences may arise from variations in the thickness of the calcareous deposit; such as are continually seen in the polypidoms of Zoophytes, and in the shells of Mollusca. Without at present entering in detail upon the question of specific distinctions, I may mention that the genus Nummulina appears to me to be divisible in the first instance into two subgenera; of which one shall comprise the species in which the investing whorls are in close apposition with each other, except at their margins, so that the chambers of each whorl surround the preceding, without covering them ; whilst in the other, the new chambers are prolonged over those of the preceding whorl, so that the investing whorls of the shell are only connected with each other by the prolongations of the mter- cameral partitions. For the further subdivision of these groups, I am disposed to be- lieve that the modes of arrangement of the prolongations of the septa between the contiguous surfaces of the investing whorls, will prove to be a character of great value in addition to those on which reliance is at present placed ; as will, also, the disposition of the perforations which I suppose to give exit to the pseudopodia. I may remark, that the genus Lycophris, created by Montfort for the reception of certain species in which the superficial punctations caused by these perforations are especially noticeable, cannot be any longer maintamed; since my examinations prove, not merely that these perforations are common to Nummulites in general, but that the so-called Lycophris scabrosus of Sowerby is nothing else than an ordinary Nummulite, whilst the Lycophris dispansus and Lycophris ephippium of Sowerby do not belong to this group at all, but are indubitable Orbitordes. ORBITOLITES. There can be no doubt, that, under this designation, various objects have been assembled which have no real relationship to each other. My observations have been made upon Orbitolites complanata of the Paris basin, and upon a recent species from the Australian seas, very closely allied to it, which is referred to by Prof. EK. Forbes (Quarterly Journal of the Geological Society, vol. iv. p. 12) as having been apparently known to Defrance, and as probably the Marginopora of 1849.] CARPENTER ON THE STRUCTURE OF ORBITOLITES. ol Quoy and Gaimard; and which bas been recently brought again under the notice of naturalists by Mr. Jukes, who collected it in considerable numbers. These two agree closely in every particular save the form of the superficial celis, which in the O. complanata are nearly round (fig. 30), whilst m the Australian specimen they are oval, or rather almost quadrangular (fig. 29); they must un- questionably be regarded, therefore, as nearly allied species of the same genus; so that, if the O. complanata is to be regarded as the fossil type of the genus, the Australian species must be considered as the recent, and the generic term Marginopora must be dropped. In both we find that the cells of the surface are closed, unless laid open by abrasion, and that the only real apertures exist at the margin; so that the designation Marginopora is really as applicable to the one as to the other. The structure of the Australian disk, as shown by a thin section parallel to its surface, is delineated in fig. 24, in which the cells are seen to be arranged with great regularity in concentric rows. It is only near the margin of this section (as at a, a), however, that its plane has passed sufficiently near to the surface, to show the cells in the oval form which they there present ; elsewhere the section has traversed a deeper stratum of the coral, in which the cells present a rounded section when cut across. This difference in the form of the cells as they pass down obliquely into the polypidom, is shown on a larger scale in figs. 25 and 26; of which the former represents the oval cells of the surface, laid open by a section passing through their plane, and the latter a corresponding section of the round cells or passages of the interior of the polypidom. Fig. 23 is a section of O. complanata taken in the same direction as fig. 26, and exhibiting a slight difference in the arrangement of the partitions, which causes the entire disk to present some resemblance, when thus examined, to the back of an engine-turned watch. The structure of the interior of the disk, as shown by a vertical section, is exhibited in fig. 27 ; in which we see the oval cells of the two surfaces, a, a, divided from each other by regular partitions, and covered-in above by complete opercula; whilst in the intervening portion of the disk, we see nothing but a series of round apertures that seem less regular in their arrangement. If such a section be made close to the margin, we lose the superficial cells, but we bring into view the openings of the deeper rounded cells upon the margin itself, as shown in fig. 28. I am not altogether confident in the correctness of my interpretation of these appearances, which are faithfully represented in the adjoming figures; but I am disposed to believe that if this disk was really formed by an animal or collection of animals of the Bryozoal type, the round passages opening at the margin, and penetrating obliquely into the polypidom, so as to be cut across both im horizontal and vertical sections, constitute the real habitation of the animal ; and that the ovate cells, which form so pe- culiar a layer upon the surface, are a later production, not improbably for the reception of ova. These ovate cells would seem to communi- eate with the cylindrical passages beneath, by means of two small apertures in each cell, as shown in fig. 25. 32 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 2, ORBITOIDES. In adopting the generic name which M. D’Ozbigny has conferred upon the fossil previously termed Nummulites Mantelli (Quarterly Journal of the Geological Society, vol. iv. p. 12), and in extending it to several other species, of which some had been previously ranked among Nummulites, and others among Orbitolites, it is proper for me to state that I am unacquainted with the definition of the genus proposed by that distinguished paleeontologist, which has not, so far as I am aware, been yet made public. The institution of the genus appears to me to be required for the reception of a number of fossils, which my own inquiries have led me to recognize as presenting a type of structure so dissimilar to that of either of the groups just named, as well as to every other with which I am acquainted, as to render their separate association desirable. My account of the genus will be principally drawn from the species just named; of which, through the kindness of Sir Charles Lyell, I have been enabled to examine many excellent specimens from the nummulitic limestone of Alabama, whilst by the liberality of Sir Roderick Murchison I have had the opportunity of examining specimens of what I have no hesitation in regarding as an édentical species from the nummulite limestone of Cutch. The Orbitoides Mantelli is a discoidal body, sometimes attaining the diameter of an inch or even more, and having a thickness of about a tenth of an inch near the centre, but gradually thinning away towards the edges. No traces of cells are visible upon its ex- ternal surface ; but when it is split through the medial plane (which is the case with many of Sir Charles Lyell’s specimens), the exposed sur- faces present a closeresemblance to the exterior of an Orbitolite; having numerous cells with rounded or somewhat oval orifices arranged in regular concentric rows, as shown in fig. 31, which represents a small portion of the interior structure disclosed by a fracture which has laid open some of the cells, but has left others with their covers un- broken. The resemblance of the surface of this central layer of cells to that of Orbitolites complanata (fig. 30) will be apparent on a comparison of the figures; and there is also a great similarity in the aspect of the cells, when seen in a section parallel to the surface (fig. 21), to that of the cells of the recent Orbitolites of New Holland, when crossed by a section taken in a similar direction (fig. 26). But these resemblances end; for we shall find that both in the structure of the central layer itself, and in the addition of the crust on either surface, which is totally unlike the two layers of ovoidal cells on the exterior of the Australian coral, Orbitoides is extremely different from Orbitolites. These differences are made evident by examining a sec- tion of this fossil made perpendicularly to the surface (fig. 20) ; for we then see that the cells or chambers of the medial plane form but a single layer (a, a); and that this is covered-in, above and below, by a thick crust (0, 6), which is itself composed, like the shell of Nummulite, of several layers with intervals between them. These layers, however, when carefully examined, are found not to possess the continuity of those formed by the investing whorls of Nummu- 1849.] CARPENTER ON THE STRUCTURE OF ORBITOIDES. 33 lites; nor do they bear, like these, any numerical relation to the chambers of the central plane. They are most numerous, however, as in Nummulites, over the central portion of the disk, and gradually diminish towards its margin. Their number seems to vary con- siderably in different specimens whose diameter is about the same. When a thin section is made through these layers, parallel to the surface, the structure brought ito view is very different from that of any Nummulite; for we see that it is made up of a number of distinct flattened pieces of irregular form (resembling those of O. Prattii, fig. 33), closely fitted together like the cells of the cuticle of an apple-leaf, or the portions of a dissected map. Between the successive layers thus formed, certain thin spaces are left, as shown in fig. 20, which are circumscribed by the adherent margins of the pieces between which they lie; these spaces are not unfrequently occupied, in the Alabama specimens, by an amorphous infiltration, which renders them opake by transmitted light ; in the Indian speci- mens they are filled with calcareous matter in a crystalline state, which has also found its way into the chambers of the central layer. From the degree of alteration which all these specimens have un- dergone in the process of fossilization, I am not able to give as com- plete an account as I could wish of the minuter features of this struc- ture. I am inclined to believe, however, that the several chambers of the central layer communicate with each other by four or more perforations through each septum, which some of my sections appear to me to display. I cannot trace in this species any appearance of passages by which the inhabitants of the chambers of the central layer could have communicated with the world without; but I shall presently describe two methods of communication as discernible in other species, and I have little doubt that one of them must have existed here. The structure of Orbitoides Mantelli presents on an enlarged scale all the essential features of that which I had previously made out in the (so-called) Orbitolites Prattw of Biaritz. A section of the latter fossil taken parallel to the surface, almost always brings into view two distinct structures, as shown in fig. 32; that marked a, a, and seen upon an enlarged scale in fig. 33, being evidently the representative of the external layers of Orbitoides Mantelli; whilst that marked 6, 6, and seen as more highly magnified in fig. 34, represents the chambered layer of the last-named species. That such is the true account of it, is clearly indicated by the appearances shown in vertical sections of these disks, a view of which, under a low magnifying power, is given in fig. 35; whilst a small portion of the section, more highly magnified, is shown in fig. 36. That both structures should be almost invariably brought into view by a section made parallel to the surface, is readily accounted for by the circum- stance that the disks are seldom or never flat, so that, as they are extremely thin, a plane section intended to pass through one layer must necessarily in some parts traverse the other. The chambered structure frequently presents considerable irregu- larities, as seen at 0’, fig. 32; I am not sure, however, that these are VOL. VI.—PART I. D 34 PROCEEDINGS OF THE GEOLOGICAL society. [May 2, really so great as they seem, since the apparent interruption of a row of chambers may be due to its passage above or below the plane of the section. In the enlarged representation given in fig. 34, it is shown that the septa that divide the chambers of the same row are in reality double, like the septa of the Nummulite. When we obtain a very thin section of the investing layers of O. Pratt, and submit it to a sufficiently high magnifying power, we see that each division is penetrated by a number of apertures, of nearly the same size and distance from each other as those of the shell of Nummulite (fig. 33). These apertures form a communication, there- fore, between the successive spaces that exist between the overlying layers; and in this manner the animals inhabiting the chambers of the medial plane may have drawn in nutriment from the surface. In many of the specimens of this fossil which I have subjected to mi- nute examination, the apertures in question are not visible ; in con- sequence, it would appear, of the changes induced by fossilization. Their apparent absence in the preceding species, therefore, by no means indicates their real deficiency ; and as the two species otherwise agree in almost every other respect than in their size and in the form of the chambers of the central layer, I am disposed to believe that the structure in question was common to both. Among the Biaritz specimens of this fossil are many which are more or less contorted ; and some of them are twisted into an ephip- pial form. These last, however, agree so precisely with the flattest individuals in the characters of their minute structure, whilst the transition from the one to the other seems to be effected by so many intermediate forms, that I think that we can scarcely regard them as specifically distinct. Another specimen in Mr. Pratt’s collection, however, appears to have had a very different mode of growth; for instead of being a circumscribed disk, it seems to have spread itself irregularly in every direction, and to have been attached to the sur- face of rocks, whose contour it has followed, like the Lepralia or any other incrusting Zoophyte. A section of this, taken parallel to the surface, could hardly be distinguished from that represented in fig. 32; but the vertical section (fig. 22) differs in the much greater number of incrusting layers. This might be regarded as merely an oa of greater age ; but the absence of definite size and form in the spe- cimens in question appears sufficient to justify their separation as a species distinct from the preceding. In neither case do we find any very definite markings upon the surface of the fossil, which might serve as a distinctive character. The aspect of that of Orbitoides Prattii, as seen with reflected light under a low magnifying power, is shown in fig. 37. The markings seem to correspond with the divisions shown under a higher power in fig. 33; and I have not been able clearly to trace any large punctations at all similar to those displayed by the group of species I shall presently describe, though I have sometimes suspected their existence. The resemblance of these bodies to Nummulites is sometimes greater than that which is shown by the preceding specimens. Thus in fig. 18 is shown a section of a small form which I have happened 1849.] CARPENTER ON THE STRUCTURE OF ORBITOIDES. 390 to cut through in examining a piece of nummulitic limestone. This might be readily mistaken for a Nummulite, upon a cursory examina- tion; but that it does not belong to that group is obvious from the want of numerical correspondence between the number of investing layers and that of the chambers in the central plane, as well as by the want of continuity in the investing layers themselves. And a careful comparison of it with the corresponding section of Orbitoides Pratti (fig. 35) will show that it differs from that species in no other important particular, than in the larger relative size and smaller number of the chambers in the central plane. Among the specimens obtained by Capt. Grant and Capt. Vickary from the nummulitic limestone of North-Western India, and hitherto regarded as Nummulites, I have obtained one, as already stated, which I believe to be identical with the Orbitotdes Mantelli of North America. But besides this, I have met with four or five other species, which seem to be clearly referable to the same generic type, although differing in certain important particulars. A vertical section of one of these, taken from a species hitherto, I believe, undescribed, is shown in fig. 19; and it is there seen that the central layer of cells bears an extremely small proportion to the entire thickness of the specimen (the edge of which is broken away at its lower part), and that the investing layers present the appearance of being traversed by conical passages, extending from each surface towards the central layer. These passages, being filled up with the opake matter of the matrix, look darker than the surrounding structure of the fossil. The appearance presented by a vertical section of the Lycophris dispansus of Sowerby is very nearly the same; and the surface of this body exhibits large punctations, which obviously mark the entrances to these passages. The structure of Lycophris ephippium is the same ; and it is worthy of notice that its peculiarities had been perceived and delineated by Mr. Sowerby (Geol. Trans. 2nd Ser. vol. v. pl. 24. fig. 15), who describes as pillars what are in my apprehension nothing more than the columns of opake matter filling the perforations. In fig. 13 is represented a vertical section, and in fig. 14 a horizontal section passing through the central plane, of an undescribed fossil from Scinde, which obviously belongs to the same genus, although presenting the external aspect of a Nummulite. Its diameter was about an inch, and its thickness about one-fifth of an inch. Here, too, we observe the central layer (a, a) to be extremely thin in com- parison with the layers (4, 6) by which it is invested on either side ; and these do not thin away towards the edge, as we see them to do in most other species, but the outer portion of them is prolonged from both surfaces over the margin of the disk, so as to meet (as at ¢) and completely inclose the central layer,—a peculiarity which I have nowhere else seen. I think it not improbable that this may be the adult condition of some of the smaller species. The superficial layers are evidently traversed, as in the preceding cases, by passages now filled with opake matter (d, d). The chambered layer, as seen in the horizontal section (fig. 14, a, a), closely corresponds with that of Orbitoides Prattii (fig. 32); but the investing layer is distinguished D 2 36 PROCEEDINGS OF THE GEOLOGICAL socieTy. [May 2, by the dark spots at the angles of its divisions. These spots are obviously the transverse sections of the passages already described, which are filled with opake matter; they are much larger in sections taken near the external surface, on account of the infundibuliform shape of these canals. In some instances these passages seem to have been very large and open, especially towards the external surface, as is shown in fig. 10, where they are indicated by the dark spots. But in other instances (as shown in fig. 9, a, a) these spots are di- vided by lines, which seem like delicate partitions dividing the entire canal into smaller passages. This harmonizes well with the idea that each passage might have given exit to a fasciculus of pseudopodia, like that which we have supposed to issue from the passages in Num- mulite, which bear so close a resemblance to those now under con- sideration. After a careful survey of the characters presented by the group of fossils I have been describing, I feel strongly inclined to the conclu- sion that their affinity is rather to the Nummulites than to the Orbi- tolites, and that the animals which formed them are more likely to have been Foraminiferathan Bryozoa. I cannot see any strong pomt of real resemblance between Orbitoides and Orbitolite, the difference in the position of their respective chambered layers being kept in view ; on the other hand, the resemblances between Orbitoides and Num- mulite are very close ; whilst the differences are by no means so great as those which exist among other members of the singular group of Foraminifera, and which seem chiefly to depend upon variations in the mode of gemmation. The Foraminiferous character of Orbitoides appears further to be indicated by the presence, in all the species I have examined by sections taken through the centre, of the large globular cavity (fig. 35, a), resembling that which is stated by M. D’Orbigny and Mr. Williamson to be the ordinary form of the first segment of the Fora- minifera, whatever may be the form which the compound structure may subsequently present. EXPLANATION OF THE FIGURES. (Puares III. to VIII.) Fig. 1. Transparent section of Nummulina levigata, nearly parallel to the median plane, passing at the upper part through the marginal portion, and at the lower through the central portion, of one of the investing whorls, and showing the irregular form of the perforations, which are here filled by a crystalline infiltration of carbonate of lime. Magnified 10 diam. Fig. 2. Transparent section of Nummulina levigata, through the median plane, showing portions of several successive whorls: at @is seen a sudden en- largement in the size of the chambers ; and at ¢ is seen a narrow whorl intervening between two broader ones, d and d. The chambers are filled by a crystalline infiltration of carbonate of lime, which, in many of them, has a deep tinge in the centre of the deposit, apparently de- rived from the presence of carbonaceous matter. Magnified 10 diam. Fig. 3. Fragment of Nummulina levigata obtained by fracture through the median plane, and showing the manner in which the marginal whorls are con- tinued as investing layers over those previously formed, and in which the marginal septa are prolonged between these layers; showing also that each septum is composed of two layers with an intervening space. Magnified 12 diam. 1849.] CARPENTER ON NUMMULINA, ORBITOLITES, ETC. 37 Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Big. Fig. Fig. Fig. 4, Fragment of Nummulina levigata obtained by fracture in a direction per- pendicular to the median plane ; showing the chambers, @ to a’, on that plane, invested by successive layers above and below; 4, 8, the septa between the chambers of the medial plane; c, c, passages between the inner margin of these septa and the outer margin of the preceding whorl ; d, a chamber in the fourth whorl from the margin, invested by four layers ; e, achamber in the tenth whorl from the margin, in- vested by ten layers ; /, f, investing layers; g, g, spaces between these ; h, h, intervening septa prolonged from the marginal septa. Magnified 20 diam. 5. Supposed animal of Nummulina, after MM. Joly and Leymerie. 6. Fragment of Nummulina levigata, obtained by fracture through the central plane, showing the doubleness of the septa through their whole course, and the separation of the two layers at a,a, to surround the perfora- tions ; showing also the minute canals in the walls of the chambers, and the openings of these canals into their cavities; and exhibiting the con- tinuity of the marginal septa with those which divide and support the investing layers. Magnified 24 diam. 7. Fragment of Nummulina levigata, broken so as to display a marginal septum and its perforations ; a, septum, marked with minute orifices ; 6, situation of principal passage, formed by the confluence of minuter apertures ; c, the outer margin of the invested whorl. Magnified 45 diam. 8. Fragment of Nummulina levigata, fractured through the median plane and at right angles with it, showing the perforations, a, a, &c., passing continuously from the surface to the septa ; these passages being filled up, in this specimen, by an infiltration of crystalline carbonate of lime. Magnified 24 diam. 9. Transparent section of Orbitoides (from the same specimen as figs. 13 and 14) through the investing layers, in a direction parallel to the me- dian plane; showing the vertical perforations, a,a, filled up with opake infiltration, and divided by delicate septa into smaller apertures. Mag- nified 60 diam. 10. Transparent section of Orditoides (species undescribed) through the in- vesting layers, in a direction parallel to the median plane, but near the external surface, showing the large apertures, a, a, of the perforations, filled up with opake infiltration. Magnified 60 diam. 11. Transparent section of Nummulina obtusa through the investing layers, in a direction paralle! to the median plane, showing the perforations, a, a, filled up with opake infiltration. Magnified 60 diam. 12. Transparent section of Nummulina complanata, in the same direction, showing the perforations elongated into slits, a,a, divided by trans- verse septa; and the metamorphosis of the tubular shell into an appa- rently prismatic structure, J,b. Magnified 90 diam. 13. Transparent section of Orbitoides (species undescribed), taken in a direc- tion vertical to the median plane; showing, a, the chambered layer occupying that plane ; 0,4, thick investing layers, the prolongations of which extend beyond the central layer and inclose its margin, as seen at c, and the vertical perforations, d, d, filled with opake infiltration. Magnified 16 diam. 14. Transparent section from the same specimen, taken through the median plane; showing, a, a, the median chambered layer, and J, d, the investing layers (a portion of which, more highly magnified, is shown in fig. 9). Magnified 40 diam. 15. Transparent section of a portion of Nummulina levigata in a direction perpendicular to the median plane (as in fig. 4) ; showing, a, a, the shelly layers cut through vertically, exhibiting their minutely tubular structure ; b, 6, modification of that structure at the margins of the whorls; ¢,c, the marginal chambers; d,d, the perforations infiltrated with trans- parent crystalline deposit. Magnified 60 diam. 16. Transparent section of Nummulina levigata, in a direction parallel to the median plane, to exhibit the structure of the shell inclosing the mar- 38 Fig. Fig. 17. 18. 19. . 20. g. 21, 22. » 23. 24. . 25. . 26. ye . 28. 5S . 30. ago . o2. . 3d. g. 34. 35. . a6. PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 2, ginal chambers; @, a, a, a, shell-wall of portions of the four chambers sepa- rated by the septa 0, 4,4, perforated by minute orifices, which are those of the parallel vertical tubuli shown in fig. 15, and traversed irregularly by canals, ¢,c, which open into the chambers by distinct orifices, d, d, and terminate in the intraseptal spaces. Magnified 60 diam. Transparent section of Nummulina complanata, in a direction vertical to the median plane, showing the several investing layers in close appo- sition with each other, and not separated by prolongations of the mar- ginal chambers. Magnified 6 diam. Transparent section of Orbitoides (undescribed species), in a direction vertical to the median plane, presenting, in the size of its chambered layer, a close resemblance to the Nummulitic structure. Magnified 20 diam. Vertical section of Orditoides (undescribed species from Scinde), with a very thin chambered layer, a,a, and the vertical channels (filled with opake infiltration) of unusual size. Magnified 9 diam. Vertical section of Orbitoides Mantelli, showing the chambered layer, a, a, occupying the median plane, and the investing layers, b, b, above and below. Magnified 60 diam. Section of Orbitoides Mantelli through the median plane, showing the form of the cells of the chambered layer, partly filled by calcareous infil- tration. Magnified 60 diam. . Section of Orbitoides (undescribed species from Biaritz) in a direction vertical to the median plane. Magnified 30 diam. Section of Orbitolites complanata through the median plane. Magnified 60 diam. Section of Marginopora (Orbitolites, recent Australian species, unde- scribed) through the median plane, but passing through the more super- ficial portion near the margin, at a,a,a. Magnified 10 diam. Portion of the same, taken near a, a, and showing the form of the cells near the surface. Magnified 60 diam. Portion of the same, taken near the centre, and showing the form of the cells nearer the median plane. Magnified 60 diam. Vertical section of the same, showing the single layer, a, a, of superficial chambers on each surface, and the structure of the intervening portion, 6b, 6, of the disk. Magnified 60 diam. Thin slice from the edge of the disk, showing the pores opening on its margin. Magnified 90 diam. Portion of the surface of the same, viewed as an opake object, showing the superficial chambers, some of them closed in, others laid open by the abrasion of their covering. Maguified 60 diam. Portion of the surface of Orbitolites complanata, viewed as an opake ob- ject, showing the superficial chambers, closed in at the lower part of the figure, laid open by abrasion at the upper part. Magnified 60 diam. Portion of the surface of the chambered layer of Orbditoides Manfelli, showing the chambers covered in and a few laid open. The investing layers have here been removed. Magnified 30 diam. Transparent section of Orbitoides Prattii, passing through the median plane; a,a, the investing layers; 0, portions of the median chambered layer, showing at 0’ a very irregular arrangement of the chambers. Mag- nified 12 diam. Portion of fig. 32,a, more highly magnified, showing the form of the cells of the investing layers, and the perforation of the shelly substance by minute tubuli. Magnified 60 diam. Portion of fig. 32,4, more highly magnified, showing the form of the cells of the chambered layer. Magnified 60 diam. Vertical section of the entire disk of Orbitoides Prattti, showing the median chambered layer, and the investing layers above and below; at a is seen the large globular cell in which the chambers of Foramini- fera always seem to commence. Magnified 10 diam. Portion of the same section more enlarged, showing the chambered layer, Quart. Geol. Jour. Vol.VI. PLU. ies 2, Nummuline levigata, 6, supposed animal of Nummulina. Jo ee = Wed ie? Ps ; saben ial Salt \ j u Pie Fy 6 3 . + a ‘ f sh 4 (eu “ * \ ‘ PE vs Y ‘ " ’ . thn pas 4 s a ¥ def Pe hihee 9 ) hy , ‘ > 3 - 5 - A a , 7 ) 4 ‘ << ‘ iyi 8 SA wet 2 . Bog 5 - md “s zr ‘ \ = is ‘ i. +. an r ‘ % ot #% ae a onl 4 A. ’ : . - a ; any * '* “ye - = br b Bile ee me as ke heey ) “4 7 * is é CSS maw SONS Se KA eee ~ } i “ t.% y u vgs Gye > » & re Ta ia ~~ pa ‘ A oh he ; su f eae ic ra 4 iv’ * vy 7 ’ . Ring Ee” % — = ‘ , ‘ eee ' * : in) s f . y { + “ ‘ D 4 neues ue 8 ™ OF : ‘ A - ‘ ish Ni a rw wee eye 5 * OuareCceal. Jour Vol Vik. PR Ve 6.7.8. Nummulina laevigata. 9. Orbitoides (undescribed species) 10. Orbitoides (undescribed species) 11. Nummulina obtusa 12. Nummuhna complanata | ate le i i | | f we t at \ i ; | y . : | | . : | | i . | 7 | 1 | hee | = 5 i 7 “| | j fs . oy . . | 3 ] 4 : | 1 | | : 1 | | ‘ | | = a 1 a id | a eae | 7 y #4 . > , | iY ly : | ; ' / i “ | ’ 3 é | : Fi wage ; y , | ; } i : “¢ | a | > Ape" | F ‘ ' Te i i | | . t a's . , y 7 * - 3 i; ‘1 4. ‘ : i] | | ' f * : « 4 $ 4 | ' > “ 7 ; 7 A | | \ . | . . i ; | b 3 | ¥ ; | | = Quart. Geol. Jour. Vol. VI. FPL.Y. = Gee ANTTELLLLCU LT) EEL Loe em Re r rts Erk s Ne ieee ee ee TAIL ily, Si cme rsa i nies ti JT agian mee VUKT CITC IT} CUP ETE acWanvnay Aa PUT meee OUIRRCUONONOUNIE te 4 4 = HT LET 7] BS ony ORR Ee FCS Vive will LS ih nt Wi : tH i ed i suo \i 5, a Zz Say anti » atti or ae Ta xy ae he eon z ay oN > ss SAAS NTR a: o 2 Ay a, Soe 0,32 232 13. 14 .Orbitoides (undescribed spectes) 15.16. Nummulina levigata. i‘ = ree ? oS * : = 7 A 2 : : nat ‘ Pa a - ~ ‘ =F ‘ ‘ » ; % ; ‘ roait « = £ ’ ’ i“ . x " . ¥ : ts a > ’ 5 . ; - : * Us “i ie ig 17. Nummulna complanata, 19. Orbitoides (undescrrbed species) ao PON LOULES (undescribed spectes) Ciare GoOl Jour Voli, Pl Vi. a i : Speedin se tee Orbitorides (undescrthed SPecres ) 21. Orbitoides Mantelh Do, Chelonuiolucas complanata r 2 PG [eee ye ee a a : : tthe TS ome a - ad ia” wt eo <>. ¥ os - he 4 “i ep, igen, ee ‘ . : t= ~— * e! c t * a 7 a Zz 3. 3 7 { 5 * ; F Se, * e = a 7 % E nd < = a“ , i , = 3 ore - . os fl cS E i > LJ >> Re 7.” 2 > Z ‘ sé #\ g 4 . ~ +} ~ ‘ “ ‘ s ; ; a . bt: a ) “< 4 a s . “a ‘ om L * iy «£ a A ; Tt ’ -_ e * ‘ ras! " = * . ! N ‘ i ‘ > ' — = r fi’ > » nF a iy a 4 , ’ , * a 3 ¥ ] : . i ? . ; s al : * * 3 ; ad re ” . hg ; 2 , q se ¥ - a a i, Guart, Geol. Jour Nol Ni.P scribed) ecles (unde age Sp Mantelli aha alg Aust ) r Sl Orcs CE 1a ) s) bitolite lamlaiyeus (Or at Orbitolites « reinopora 24-29. Ma 30 | 1toldes MD JE ~ ST) Con Quart. Geol. Jour VolNl. PV. SS SSe= SAB Oooo) 6,5) Orbr homes meratiiln 1849. ] MOORE ON TERTIARY BEDS IN SAN DOMINGO. 39 ‘a,a, in the median plane, and the investing layers, 6,5, above and below. Magnified 90 diam. é Fig. 37. Portion of the surface of Orbitolites Prattii, viewed as an opake object, showing the absence of any definite indications of cells or chambers. Magnified 30 diam. May 16, 1849. C. Bagot Lane, Esq., C.E., was elected a Fellow of the Society. The followmg communications were read :— 1. On some Tertiary Beds in the IsLAND OF SAN Domineo: from Notes by J. S. HENtKER, Esq., with Remarks on the Fossils, by J. Carrick Moors, Esq., Sec.G.S. In the north-eastern part of the island of San Domingo, at an average distance of about 30 miles from the sea, runs a range of mountains with an east and west direction, consisting of mica schist. Between this range and the northern sea an extensive tertiary formation occurs, being about 30 miles broad, and at least 100 miles in length from east to west. It is intersected by several rivers, the principal of which is the Yaqui, on which stands the town of San Jago, distant from the sea about 20 miles, and elevated more than 2000 feet.above it. The rivers have cut narrow channels through the strata, which are thus exposed in perpendicular cliffs often 200 feet high. These cliffs near the bottom consist of a bluish sandy shale, whence Mr. Heniker ex- tracted the greater part of the fossils shortly to be mentioned. Higher up the beds become more argillaceous, and contain but few shells, with some corals. This formation is overlaid conformably by tufa- ceous limestone, which has suffered much denudation, and forms a low range of arid hills, about 500 feet high, resembling chalk downs in their rounded outline, and scantily covered by a dwarfish vegeta- tion. At the foot of these hills, in loose sand covering the shelly deposits, Mr. Heniker found fishes’ teeth. These formations dip gently to the N.N.W., and intermediate between them and the sea a red sandstone is found, dipping also to the N.N.W., but at a much more considerable angle. Mr. Heniker has not been able to ascer- tain its relation to the limestone and shale, but he suspects it to be older. No organic remains are found init. From the shales and the sand which caps them Mr. Heniker procured the following fossils : —fishes’ teeth, a crab, 84 species of mollusca, an echinoderm, 18 spe- cies of coral, numerous foraminifera, dicotyledonous wood. Sir Philip Egerton, who obligingly examined the fishes’ teeth for me, states that they belong to the Carcharodon megalodon, Agassiz, found in the crag, the Malta beds, the miocene formations of Ame- rica, &c. The Corals have been laid before Mr. Lonsdale, who has not had time to examine them in detail: he however informs me that they belong to 18 species; some of them, apparently taken from a super- 40 PROCEEDINGS OF THE GEOLOGICAL sociETy. [May 16, ficial or vegetable soil, have a more recent aspect than others which are found in a light-coloured sand: none of them were referable to the fossil corals of America known to Mr. Lonsdale. The Echinoderm is a scutella closely allied to, if not identical with, a recent species. Mr. Morris, who kindly examined the Foraminifera, informs me that four are identical with the following known species :— Nodosaria raphanistrum ... Fossil at Malta, &c. AMMNIS, 2.5 iae-aceses sees Fossil at Vienna. Robulina cultrata ............ Recent, and fossil at Vienna, Sienna, &c. Rosalina Beccarii ..........0. Recent, and fossil at Bordeaux. Others belong to the genera Tewxtularia, Dentalina, &c. The Mollusca were compared by Mr. G. B. Sowerby and myself with such recent and tertiary shells as we could get access to, more especially with the rich collection of American tertiary shells m the possession of Sir Charles Lyell, who most kindly permitted us to con- sult his museum. The result was as follows. Omitting such as are too imperfect for specific determination, the shells are referable to 77 species, belonging to the following genera :— No. of Species. No. of Species. CONGS, "Soh secntancs epee eee 9 Turbinellus .......... sadieeces 3 Oliva ress) kes ee nee eee 2 Pleurotoma <...s.cccacteoseee 6 Cyprea [Ae eis. the. Be l Cerithium | ..22..cceee eee 2 Marginella | ,.3..63.3-2ei2.ces 1 SOLATIUM « <--5.00s<0sns-e sees 1 Wolitta do5: ao, 0. peeeun cesses 2 Petaloconchus ....s-.ssneeeee 2 IMGT EX (252 a2 605 fen ceee esas 1 OSHS. 502k. oe ssn 3 Pyela eo ask ee eke 1 Spondylus..-..225..s2.-e eee 1 MUSHS (ESS J eeee eee 2 —17 Hasciolarias| ...265.:s000eesbe 2 =: Cancellaria, -'...:¢0toneacc sees 1 7g Of these Mr. G. B. Sowerby considers 13 to be identical with ex- isting species; while with respect to two more he entertains some doubt. The following is the list :— . Oliva hispidula, Zam. (var.)... Hab. West Indies. Columbella mercatoria ......... », West Indies. Nassa incrassata (var.) .......0. » Brit. and Mediterr. Phos Veraguensis, and var. ... ,, Coast of Veragua, Pacific. 5. Triton femoralis .....0.:006...008 »» West Indies. Turbinellus ovoideus .........,.. », West Indies. Cancellaria reticulata (var.) ... ,, West Indies. Natiea saleata. oc. x..5o06 aac eee »» West Indies. Bulla strata, iam: ~ os .0cc..cess », West Indies. 10. Venus puerpera, Linn. ....2.005 » Indian seas. 1849.] MOORE ON TERTIARY BEDS IN SAN DOMINGO. 4] Lucina pensylvanica, Lam. ... Hab. West Indies. ——— tigeT1vina.......00060...s0000. » West Indies. 13. Chama arcinella .............0.00. » West Indies. Tellina ephippium? ............ », Indian seas. Ostreca Vanginica es? sssee-eccern: » Coasts of America. Of these 13 recent shells, 5 have been found fossil in the following localities :— Nassa incrassata ...0......0006 Bordeaux, Dax, Cor. Crag, Sub-Apennines, Sicily. Bulla striata, Lam. ........+06 . Montpellier, Perpignan. Chama arcinella ...........0... Miocene beds of United States. Lucina pensylvanica, Lam. ... Miocene of Piedmont. TIZETTINA ....000-..000000008 Bordeaux, Sub-Apennines, &c. The large Ostrea Virginica is also found fossil at Bordeaux, and in American miocene beds. Of the remainder, two are closely allied to Pleurotoma oblonga, of the Bordeaux and Touraine beds, and P. vulpecula, of the Sub-Apen- nines. An Oniscia and a Turbinellus are not to be distinguished, by the engravings or descriptions, from O. harpula and T. Wilsoni of Conrad, in the upper eocene of the Mississippi; and an Ostreea is iden- tical with O. callifera of the Paris basin and the Brussels beds. Mr. Sowerby has favoured me with descriptions of 59, which he considers new ; these are appended to this notice, and in fact form the more important part of it. Shells of the following genera also occur, but not sufficiently preserved for specific determination :— Murex, Turritella, Turbo, Pasithea, Rissoa, Dentalium, Cytherea, Cardium, Pinna, Inthodomus. Of the new species there is one which calls for a remark. Mr. Lea* has formed a new genus, Petaloconchus, for a shell, found in the miocene beds of Petersburgh, Virginia, which resembles a Vermetus in general characters, but differs from it in having two internal raised plaits or bands running spirally along the columella, like those of a Volute. In the young state of the shell these bands either do not exist or are very faint, and they also seldom continue to the mouth. Finding a shell with these characters among the San Domingo fos- sils, I was curious to learn whether any known shells described as Vermeti might not also possess them, although, for want of a fracture in the more central parts, it had not been observed. I accordingly examined all the vermetiform shells I could find, and satisfied my- self that the following three well-known shells also have this charac- ter, and are therefore true Petaloconchi :— Vermetus subcancellatus ... Fossil in Touraine, Bordeaux. HELROVAUS. Sognoaenooqesasoen », Bordeaux? Piacenza, Crag. glomeratus (Brocchi)... » Bordeaux, Sienna, Zante. I have not found one species among recent Vermetit, nor in for- * Trans. Amer. Phil. Soc. vol. ix. p. 229. T Vermetus subcanceilatus and V. glomeratus are enumerated by Dr. Philippi as recent and fossil in Sicily. Through the kindness of Mr. Hanley I have seen spe- cimens of each of the recent shells, which he had received from Dr. Philippi: 42 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, mations older than those of Touraine or Bordeaux. Thus, of the four described species, including Mr. Lea’s Petaloconchus sculpturatus, three are confined to miocene beds, and the fourth occurs in both miocene and older pliocene formations. Some probability hence arises that the San Domingo beds which contain this fifth species are also to be referred to the middle tertiary epoch. In speculating upon the age of these deposits, the first question is, whether all their organic contents belong to the same formation. Upon this point the evidence of Mr. Heniker, though not a practised field-geologist, deserves great weight. He informs us, that though the fossils were collected from five different localities, by far the greater number were procured by himself from one spot, and the remainder from beds apparently in the same stratigraphical position ; so that he entertains little doubt on this head. As some corroboration of this view, I may state, that the matrix in which the fossils were imbedded appeared to me of only two kinds, and different specimens of the same fossil were frequently incrusted with each. Assuming therefore this to be true, we have a deposit containing 77 species of Mollusca, of which 13 are unquestionably recent, and 2 doubtful. Excluding the doubtful, the proportion of 13 to 75 is exactly 171 per cent.; and should the 2 doubtful hereafter be identified with recent shells, the proportion of 15 to 77 is 192 per cent. It is obvious that this formation is of quite a different order from the fossil beds in Barbadoes and Antigua, every species in which is now found living in the adjoining seas. Neither have I been able to iden- tify one shell with those from the older tertiary rock m Barbadoes, described by Sir R. Schomburgk, or those from Jamaica in the So- ciety’s collection. If we take as our guide the law of the proportion of recent to extinct forms, the ratio of 17 or 20 per cent. would refer this formation to the miocene period of Europe: and the facts that all the Foraminifera and Mollusca which have been identified with known fossil forms occur in beds of that high antiquity, and perhaps in one or two cases older,—the presence of a genus of shell of which no species has been found in beds older than the American miocene or newer than the Sub-Apennines,—the occurrence of the teeth of the great Carcharodon, considered by Agassiz as very characteristic of miocene formations,—together with the general resemblance and the close analogy of some of the fossils to those of Touraime and Bor- deaux,—all seem confirmatory of this view. It may seem remarkable that there is no greater specific resem- blance between these shells and those from the miocene beds of the United States. But when it is remembered that the most southern miocene deposits of America are in lat. 33°, while those of San Do- mingo are in lat. 19°, a difference equal to that between Rome and Edinburgh, this will scarcely invalidate the conclusion. neither of them has plaits on the columella; and as it is impossible to doubt the accuracy of that gentieman’s identification of the recent shells with the Sicilian fossils, I cannot but suspect that these Sicilian shells are distinct from their two synonyms in the Touraine, Bordeaux, and Piacenza beds. 1849. | MOORE ON TERTIARY BEDS IN SAN DOMINGO. 43 Mr. Conrad* has lately described a formation in South Carolina, in the bluffs of the Mississippi, which is distinctly newer than the eocene beds of Claiborne. Out of 177 shells, it contains only two which are common to it and the subjacent eocene, while not a single species is identical with existing forms. In the upper part of it are found the teeth of the Carcharodon megalodon. 'To this formation Mr. Conrad has provisionally given the name of upper eocene. Two of the shells are undistinguishable, by their engravingsand descriptions, from two of the San Domingo shells, and a great many are closely allied. Should it prove on further examination that the San Do- mingo beds are referable to two formations, the recent species being principaily confined to the upper and the extinct to. the lower, I think it probable that the lower would be found nearly related to those so-called upper eocene beds in South Carolina. There is a character attached to a portion of this collection which is too remarkable to leave unnoticed. Mr. Sowerby was much struck with the resemblance of many of the shells to recent species inhabiting the seas of China, Australia, and even the western coast of America ; a resemblance so close, that that naturalist hesitated before pronoun- cing them to be distinct ; whilst he identifies without any doubt two of the shells with the recent Venus puerpera (Linn.) of the Indian Ocean, and the Phos Veraguensis which was dredged up in the Bay of Veragua by Mr. Hinds, during the Voyage of the Sulphur. It is certainly remarkable to find a shell living in the same latitude with its fossil analogue, and separated from it only by a narrow isthmus, when it is recollected upon what grounds the high antiquity of the division of the Atlantic and Pacific Oceans into distinct faunas has been established. M. D’Orbigny has shown that the tertiary beds which flank the two sides of the Cordilleras do not contam one species m common. Mr. Conrad has lately published a list of all the recent shells known to him which are found in the American miocene, 49 in number, which without an exception are Atlantic species. Suir C. Lyell has shown that most of the recent shells found in the miocene of the United States are confined to the western shores of the At- lantic. To this there is one exception, the Calyptrea costata, which is found living at Valparaiso and fossil in American miocene beds. It must be remembered that M. D’Orbigny’s conclusions are formed from shells derived from latitudes 31° to 40° S.; and the most southern of the North American miocene beds are in lat. 33° N.: so that a channel or sound may have existed in the equatorial parts during some portion of the tertiary period, by which some few of the tropical shells may have migrated from the one ocean to the other, while those living 30° to the north or south of the line would be as effectually separated as those actually livig in the two oceans 30° north of the Straits of Magellan. It should be borne in mind that the Isthmus of Panama is not merely narrow, but low land: the con- tinuity of the Andes (I quote Mr. Hinds’ words) is here quite broken ; and instead of the table land north of Nicaragua of the height of 4500 * American Journal of Science, 1846, New Series, i. 44 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, feet, or the peaks of the Andes to the south reaching to 11,000 feet, the Isthmus nowhere attains 1000, that is, one-half the height through which these beds of San Domingo have been elevated since their deposition. It is to be hoped that Mr. Heniker, to whom we are indebted for this interesting collection, will continue his researches, and clear up the doubt which I have ventured to suggest, whether these fossils belong to the same or to two formations of different geological age. Descriptions of new Species of Fossil Shells found by J.S. HENIKER, Esq. By Mr. Georce B. SowEersy. Conus HAyTENSIS. Testa oblongo-turbinata, conica, levis, crassiuscula, spira subproducta, spiraliter striata, anfractibus primis subcoronatis, ultimi margine postico rotundato an- guloso, ad basin striato; apertura ampla, postice rotundato-emarginata ; canali subreflexo. A variable species ; at the same time it cannot be confounded with any known species. Conus syMMETRICUS. PL. IX. fig. 1. Testa turbinata, crassiuscula, breviuscula, granulosa, spira brevi, spiraliter striata, anfractuum marginibus angulatis; ultimo anfractu zonis angustis, pluribus, ele- vatis, granosis, lateribus zqualibus, canali subproducto, leviter reflexo. A beautiful small Cone, having the last volution covered with gra- nular zones. CoNUS STENOSTOMA. Testa turbinata, regularis, crassa, leevigata, spira mediocri, subacuminata, lineis incrementi obsoletis solum conspicuis; anfractibus primis leviter subcoronatis, ultimo postice angulato, mediane et antice transversim lirato, liris subdistanti- bus, subprominulis ; apertura angusta, labii externi sinu postico magno. Remarkable for the narrowness of its mouth and the great size of the posterior sinus of the outer lip, as evidenced by the lines of growth on the spire. CONUS PLANILIRATUS. Testa turbinata, crassa, transversim sulcata, spira breviter acuminata, levi, sub- striata; anfractu ultimo liris elevatis, numerosis, confertis, superne planis cincto; interstitiis longitudinaliter tenerrime striatis. About twenty prominent, flat-topped ridges may be counted on the last volution. CONUS MARGINATUS. Testa subturbinata, utrinque subzqualis, sulcata, spira conica, subacuminata, an- fractuum marginibus prominulis; anfractu ultimo transversim costellato, costel- lis 16 acutangulis. Deeply grooved externally, and having the edge of the volutions composing the spire rather prominent. 1849. ] MOORE ON TERTIARY BEDS IN SAN DOMINGO. 45 Conus DoMINGENSIS. © Testa turbinata, subpyriformis, crassiuscula, levis, spira elevata, spiraliter striata, anfractibus primis subcoronatis, marginibus subelevatis, ultimo anfractu postice subventricoso, antice striato, striis granosis, moniliformibus. This is a somewhat variable species, particularly in the elevation of the spire. CONUS SOLIDUS. Testa turbinata, conica, crassa, levis, spira subproducta, levi, anfractuum margi- nibus rotundato-elevatis; anfractu ultimo striato, striis paucis, subobsoletis, canali recto. This fossil is remarkable for retaining some traces of its living colours, the spire is marked with light rusty-brown dashes, and there are three rows of spots of the same colour on the last volution. Conus caTENATUS. Pt. IX. fig. 2. Testa oblongo-turbinata, spira producta, mucronata, anfractibus canaliculatis, ul- timo anfractu levi, antice obsolete sulcato, liris nonnullis granosis, sulcis alter- nantibus, granis paucis, parvis, distantibus. Conus CONSOBRINUS. Testa oblongo-turbinata, crassiuscula, granulosa, spira conica, elevata, coronata, spiraliter striata, ultimo anfractu zonis elevatis, angustis plurimis granosis, ca- nali subproducto. ¥ _ Also a variable species ; in one specimen the granose zones only ‘cover half the shell. It bears some resemblance to Conus cedo-nulli. OLIVA CYLINDRICA. Testa subcylindrica, spira brevi, retusa, labii columellaris dentibus validis, obtu- siusculis, calli umbilicali dentibus sex ad septem elongatis, quorum altero brevi. Cypr@a Henixeri. Pu. IX. fig. 3. Testa obovata, ventricosa, inflata, levis, dorso postice irregulariter tuberculifero, lateribus, preecipue sinistro, obsolete granosis ; extremitatibus, postica brevis- sima, antica subproducta, apertura angusta, marginibus dentatis, dentibus pau- cis, magnis, rotundatis, canali brevissimo, reflexo. This species bears a general resemblance to Cyprea Mus and seve- ral others, which occasionally have irregular tubercles on the poste- rior part of the back ; it may however be easily distinguished from all such by the dentition of both edges of the aperture, the teeth in this species, though not numerous, being large and prominent. MARGINELLA CONIFORMIS. Testa oblongo-ovata, antice acuminatior, spira brevissima, submucronata, apertura rectiuscula, angusta, labii externi margine inflexo, lato, crasso, depresso, ad api- cem continuo, margine interno crenulato; labio columellari antice incrassato, supra anfractum ultimum extenso, plicis quatuor, prominulis, distantibus, dua- bus anticis elongatis, obliquis, parallelis, antica latus alterum canalis formante, antepenultima minus parallela, postica transversa. This species comes nearest to Marginella Amygdala of Kiener ; it 46 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, differs from that species, however, in having a straight narrow aper- ture, a flat wide outer lip, its immer edge being crenulated, its large, coarse and distant columellar plaits, and in its general shape. VOLUTA PULCHELLA. PL. IX. fig. 4. Testa oblongo-ovata, levis, longitudinaliter costata, anfractibus senis subrotunda- tis, spira acuminata ; costellis plerumque antice subobsoletis ; labio externo in- tus levi, columella plicata, plicis anticis majoribus. There are apparently two varieties of this species, one of which is smaller and rather wider; its ribs are also rather fewer, and more generally somewhat obsolete anteriorly. : VOLUTA SOROR. Testa ovato-oblonga, levigata, anfractu ultimo oblique longitudinaliter costato, antice transversim striato ; margine interno labii externi denticuiato, plicis labii columellaris distantibus, posticis parvis. There is only a single individual of this species, which has lost its spire ; it is distinguishable from V’. pulchella by its greater size, and by the obliquity of the longitudinal ribs. Mirra Henikeri. Pt. IX. fig. 5. Testa oblongo-fusiformis, utrinque acuminata, anfractibus septem, spiraliter sulca- tis, sulcis majoribus minoribusque alternantibus, ad basin decussatis ; margine labii externi crenulato; plicis columellaribus duabus posticis validis, antica soli- taria obsoleta. This species is nearest in form to the recent M. filosa, which has four plicee on the columella. MITRA VARICOSA. Testa oblongo-subfusiformis, anfractibus subventricosis, liris majoribus minoribus- que asperis alternantibus, varice aspera prope suturam distincta; plicis colu- mellaribus posticis duabus, validis, tertia obsoleta. Remarkable for its two prominent columellar plicee, and for the spiral varix placed at the posterior part of the volutions near the su- ture. A fragment only exists. CoLUMBELLA HAITENSIS. Testa ovalis, anfractibus senis, spiraliter striatis, transversimque costellatis, an- fractu ultimo ventricoso; apertura latiuscula, canali brevi, reflexa, extus striata ; sutura valida; columella postice rugulosa; labio externo intus dentibus qua- tuor ad quinque induto. A very small species, not quite three-eighths of an inch in length, and nearly one-eighth in width. CoLUMBELLA VENUSTA. PL. IX. fig. 6. Testa oblongo-acuminata, crassa, anfractibus 9, subventricosis, longitudinaliter costellatis, costellis flexuosis, transversim sulcatis, sulcis crebris, costellas decus- 1849.| MOORE ON TERTIARY BEDS IN SAN DOMINGO. 47 santibus ; sutura valida; margine interno labii externi dentibus elongatis 7 ad 8 labio columellari intus ruguloso ; canali brevi, leviter reflexa. This very elegant Columbella differs entirely from any other known species. TEREBRA SULCIFERA. Testa aculeiformis, anfractibus plurimis, oblique transversim sulcatis, prope sutu- ram incrassatis, sulcis spiralibus duobus prope suturam admotis, tertio antico subobsoleto ad basin anfractis remoto. TEREBRA INZQUALIS. Testa turrito-subulata, subcylindracea, anfractibus planulatis, longitrorsum plicato- costellatis, postice linea impressa cinctis, costellis posticis obliquis, anticis ar- cuatis ; anfractu ultimo antice subangulato; columella antice biplicata. The deep impressed spiral line divides the volutions into unequal parts. TEREBRA BIPARTITA. Testa turrito-subulata, acuminata, anfractibus planulatis, longitrorsum plicato- costellatis, postice linea impressa costellis decussata cinctis, costellis posticis subevanidis, anticis subarcuatis; anfractu ultimo antice rotundato, columella antice levi. This species somewhat resembles 7. duplicata, particularly in its general shape. CASSIS SULCIFERA. PL. X. fig. 1. Testa ovato-trigona, crassiuscula, anfractibus senis, longitudinaliter sulcatis, ulti- mo seriebus duabus ad tribus tuberculorum ornato, serie postica eminentiore ; apertura lata; margine interno labii externi dentato, dentibus paucis distanti- bus ; labio interno transverse costellifero; costellis anticis prominentioribus. CASSIDARIA LEVIGATA. PL, X. fig. 2. Testa ovata, utrinque subacuminata, plerumque levis, nonnunquam transversim striata, anfractibus senis, varicibus tenuibus nonnullis ornatis; apertura ob- longa, postice acuminata, margine interno labii externi dentato, dentibus elon- gatis pliciformibus ; labio columellari antice posticeque ruguloso. Variat testa majori, ventricosiori. Oniscta DomincENsis. PL. X. fig. 3. Testa ovato-oblonga, subventricosa, crassiuscula, anfractibus senis, coronatis, de- cussatim costatis, postice subplanulatis; apertura elongata, postice acuminata, margine interno labii externi transversim costellifero, costellis sub-bifariam co- ordinatis ; labio columellari granuloso. When young the granules of the columellar lip are indistinct, and do not extend so as to cover the lip, but when full-grown the colu- mellar lip is entirely covered with granules; in which character it differs from O. cancellata. It is also distinguished from that spe- cies by the nature of the denticulations on the inside of the outer lip, which in O. Domingensis are extended across the lip. It is worthy of remark, that O. cancellata is a Chinese species. 48 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, STROMBUS AMBIGUUS. Testa ovato-elongata, postice acuminata, transversim dense striata, anfractibus octo, primis transversim costellatis, anticis duobus tuberculiferis, tuberculis parvis, rotundatis; apertura latiuscula, labio externo extus varice distincta, in- tus ruguloso, labio columellari intus postice ruguloso. Distinguished from Str. bzfrons by the rugulosities at the poste- rior inner part of the columellar lip, as well as by the form of the tubercles. Stromsus Harrtensis. Pt. IX. fig. 7. Testa suboblongo-turbinata, transversim sulcata, spira pyramidali, acuminata, subundulata, varicosa, anfractibus novem, ultimo ad dorsum tuberculato, tuber- culorum seriebus duabus, altera postica, tuberculis subdepresso-acuminatis ; altera antica, tuberculis duobus vel tribus sistente; tuberculo parvo prope la- bium remoto; apertura elongata, labii externi crassi margine inflexo. A species which closely resembles Str. cnermis of Swainson, from which it may be distinguished by its peculiarly-arranged tubercles. STROMBUS PROXxIMUS. PL. IX. fig. 8. Testa ovato-oblonga, antice posticeque acuminata, transverse striata, anfractibus novem, posticis transversim costellatis, varicosis, anticis duabus tuberculiferis, tuberculis acuminatis, ultimo nonnunquam seriebus tuberculorum duabus ; aper- tura latiuscula, subexpansa, intus levissima, canali subreflexo. This differs from Str. gracilior, Sow. (to which species it is most nearly allied), in having the inner part of both lips quite smooth, the outer surface of the two last volutions distinctly striated, and in the first volutions being transversely ribbed and not tuberculated. STROMBUS BIFRONS. PL. IX. fig. 9. Testa ovato-oblonga, utrinque acuminata, transversim striata, anfractibus octo, primis transversim costellatis, anticis duobus postice tuberculatis, serie tuber- culorum unica, tuberculis acuminatis; apertura latiuscula; labio externo extus varice unica subdistincta intus ruguloso, labio columellari levissimo. This species bears some resemblance to Str. Columba, but is very easily distinguished. TRITON SIMILLIMUS. Testa ovato-elongata, postice acuminata, distorta, varicibus quatuor ad quinque indistinctis, anfractibus octo, liris elevatis clathratis, tuberculiferis ornatis ; columella profundiuscule excavata, ad laterem canalis dentibus rugosa, cailosi- tate postice armata; labro subplano, margine interno dentato, dentibus validis, tertio maximo; margine labri externo dentibus mediocribus, continuis; canali subreflexo; anfractus ultimi parte postica interna dentibus duobus oblongis, magnis. Nearly related to Tv. decipiens of Reeve, but distinguishable by the greater coarseness of the decussating ridges and the tubercles formed at their junction. TYPHIS ALATUS. PL. X. fig. 4. Testa ovato-oblonga, subfusiformis, transversim striata, anfractibus senis, quadri- 1849.] MOORE ON TERTIARY BEDS IN SAN DOMINGO. 49 fariam varicosis, costellis brevibus intermediis; varice ultimo lato, tenui, radia- tim striato, canali longiusculo, obtecto. Distinguished by the tenuity and great extent of the wing-like varix from all known species. Murex Domineensis. PL. X. fig. 5. Testa subovata, utrinque subacuminata, trifariam varicosa, anfractibus senis, longi- tudinaliter costellatis, spiraliter valide striatis; varicibus prominentibus, rotun- datis, marginibus paucispinosis, spinis brevissimis ; labio columellari antice rugu- loso; canali breviuscula. Pyru.a Consors. Testa obovata, ventricosa, levis, transversim striata; anfractibus quinque, primis tuberculatis, ultimo seriebus duabus ad tribus postice, antice serie solitaria or- natis; apertura oblonga, lata; canali lato, brevi; columella antice subangulata, planulata. This species nearly resembles P. Melongena, Lam., which is a re- cent species from the West India islands: it may be distinguished by its shorter figure, by being more ventricose, by the pointed tubercles on the spire, and its shorter and wider canal. Fusus HENIKERI. Testa elongato-fusiformis, gracilis, postice elongato-acuminata, anfractibus pluri- mis, ventricosis, longitudinaliter costiferis, spiraliter liratis, costis rotundatis, liris acutis; canali elongata, extus lirata, margine interno labii columellaris ruguloso ; labii externo intus sulcato. Remarkable for being distinctly longitudinally ribbed and spirally grooved ; the inside of the outer lip is also grooved, and the inner edge of the columellar lip is rugulose. Fusus HAITENSsSIs. Testa elongato-fusiformis, gracilis, postice elongato-acuminata, anfractibus pluri- mis, ventricosiusculis, undique spiraliter liratis, liris prominentibus acutis, me- diana duplicata majori, longitudinaliter costatis, liris costas decussantibus; ca- nali valida, liris posticis distinctis, anticis subobsoletis. Most like F. Toreuma, Desh., but distinguished by the central ele- vated ridge being formed of two lines, and being more prominent than the remainder. FASCIOLARIA SEMISTRIATA. Testa oblongo-fusiformis, anfractibus senis, antice posticeque spiraliter striatis, mediane levibus; striis duabus elevatis prope suturam conspicuis. This species most nearly resembles F’. fusiformis of Reeve ; it may, however, be easily distinguished, by the middle part of the volutions being free from the spiral striee. FASCIOLARIA INTERMEDIA. Testa oblongo-fusiformis, anfractibus senis, primo levi papillifermi, secundo, tertio et quarto tuberculatis, ceteris ventricosis, levibus; canali longiusculo. | A single specimen with a papillary apex, like that of F'. papillosa, Sow. Tank. Cat. VOL. VI.—PART I. E 30 PROCEEDINGS OF THE GEOLOGICAL SociETy. [May 16, TURBINELLUS VALIDUS. Testa oblongo-subfusiformis, levis, postice acuminata, antice coarctata, anfractibus 6 ad 8, subventricosis, spiraliter striatis, posticis transversim obtuse costatis, intermediis subtuberculatis, anticis duobus postice tuberculatis; sutura canali- culata, margine levata; apertura magna, canali valido extus striato. This species somewhat resembles 7. Scolymus: it differs, how- ever, materially in its general form not being hexagonal; in the su- ture, whose margin is elevated and with a narrow channel; and in its tubercles, which are small and rounded. TURBINELLUS HAITENSIS. Testa subtrigona, turbinata, transversim striata, tuberculata, spira subdepressa, subacuminata; anfractibus senis, postice anguliferis, ad angulum tuberculiferis, lateribus declivibus ; antice seriebus duabus tuberculorum, quarum postica multo major; labio columellari quadriplicato ; canali extus subtuberculato. The flatness of the spire at once distinguishes this from T. pugil- laris, Lam. PLEUROTOMA HENIKERI. PL. X. fig. 6. Testa elongato-acuminata, crassiuscula, rudis, anfractibus novem, spiraliter liratis, longitudinaliter retundato-costatis, infra suturam uniliratis, deinde levibus sub- concavis ; apertura oblonga, latiuscula, labio externo valido, crasso, sinu postico distincto, columellari crassiusculo; canali breviusculo, subumbilicato, subre- flexo. In general form this species resembles PJ. maura, Sow.; there are, however, several characters by which it may be distinguished. PLEUROTOMA VENUSTA. PL. X. fig. 7. Testa acuminato-turrita, crassa, anfractibus rotundatis, confertim costellatis, in- terstitiis transversim liratis, ad suturam subdepressis, labio externo crassiusculo, patulo, sinu postico lato, profundo; canali brevissimo, subrecurvo; ultimi an- fractis tuberculo dorsali oblongo, conspicuo. In shape this species resembles Pl. gibbosa of Kiener and Pl. pal- lida of Sowerby. PLEUROTOMA CoNsoRs. Testa elongata, acuminato-turrita, anfractibus postice concavis, levibus, mediane et antice spiraliter liratis, liris costis longitudinalibus decussantibus granulis formantibus ; sutura undulata, lira parva levata antica; canali mediocri. This species bears some general resemblance to Pl. militaris of Reeve. PLEvUROTOMA HAITENsIs. Testa turrito-acuminata, elongata, spiraliter striata et lirata, liris in utroque an- fractu quatuor, centrali conspicuo, in ultimo anfractu septem, tertio conspicuo sinu distincto; canali longo, oblique lirato ; interstitiis linearum incrementi ob- solete decussatis. In general appearance this species resembles Pl. virgo: it differs, however, in the circumstance that in Pl. virgo the second ridge is generally the one that is decurrent with the notch, whereas in our fossil it is the third; this ridge has also a second line marking its edge. 1849. | MOORE ON TERTIARY BEDS IN SAN DOMINGO. 51 PLEUROTOMA JAQUENSIS. Testa fusiformi-turrita, anfractibus 7 ad 8, transversim costatis, postice subleevi- bus, antice spiraliter striatis; costis validis, rotundatis, striis distinctis supra costas decurrentibus; apertura ovata, canali breviusculo, lato, extus striato, subrecurvo; sutura costella spirali, undulata induta. Aperture and canal about two-fifths the length of the shell. This species is nearly related to Pl. oblonga. CERITHIUM UNISERIALE. Testa acuminato-turrita, antice ventricosa, anfractibus spiraliter striatis, serie unica tuberculorum ornatis, sutura distinctaé adpressa, obsolete crenata, ultimi anfractis serie tuberculorum minimorum, sutura serie tuberculorum parvorum ornata; striis spiralibus tenuissimis interruptis. CERITHIUM PLEBEIUM. Testa acuminato-turrita, nonnunquam varicosa, anfractibus undecim rectiusculis, spiraliter costatis, costis granosis triseriatis, serie postica paululum remota; linea elevata suture distincta. SOLARIUM QUADRISERIATUM. PL. X. fig. 8, a, 0, c. Testa orbicularis, depresso-conoidea, anfractibus senis, superne spiraliter granosis, granis in seriebus quatuor confertis ; prope marginem sulco valido postico, mar- gine superne infraque minutissime crenulato, infra cingulis plurimis granosis, quorum primus filiformis, minutissime crenulatus, secundus minutissimus, cz- teris majoribus; dentibus umbilici crassis. In the teeth of the umbilicus this species closely resembles S. gra- nulatum, Lam.; in all other characters it differs from every known species. PretTaLoconcuus* DominGeEnsis. PL. X. fig. 9. Testa contorta, crassa, tubulo plerumque spirali, anfractibus ad marginem inferio- rem angulatis, angulo costulisque longitudinalibus graniferis ; costulis nonnullis etiam infra angulum anfractuum graniferis. This remarkable spiral shell approaches near to P. sculpturatus of H. C. Lea, only his species does not appear from his figure to have any granular longitudinal ridges below the angle of the volutions. NATICA SUBCLAUSA. Testa obovata, levis, anfractibus tribus, ultimo maximo, callo umbilicali magno, crasso, umbilicum fere claudente. In general form this species nearly approaches to N. Mamilla; in that species, however, the umbilicus is entirely closed. In another somewhat similar species, which I believe is called N. Olla by Valen- ciennes, the umbilicus is much more open than it is in our fossil. BuLua GRANOSA. PL. X. fig. 10. Testa ovato-subglobosa, ventricosa, tenuis, transversim striata, striis paucis, di- stinctis, lineas incrementi decussatis, graniferis ; columella late marginata, sulco postico profundo ; spira inclusa. Nearly like B. hydatis mm form. * Petaloconchus of H. C. Lea, in Trans. of Amer. Phil. Soc. vol. ix. p. 229. pl. 34. f. 3. E2 52 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, BuLLA PAUPERCULA. Testa ovato-oblonga, mediane subcoarctata, levis, antice transversim striata, labio columellari antice incrassato. Carpium Hartense. Pt. X. fig. 11. Testa oblique subovata gibbosa, radiatim costata, lateribus brevibus, costis qua- tuor et viginti, quadratis, graniferis, interstitiis creberrime rugulosis; angulo postico rotundato ex umbone ad marginem inferiorem posticam decurrente. Very like C. subovale of Brod. and Sow., but wider, and distin- guished further by the squareness of the ribs. The grains on the ribs constitute another remarkable character, in which this differs from C. subovale. ARCA PATRICIA. Testa zequivalvis, quadrata, infra rotundata, crassissima, lateribus superne subauri- culatis; margine inferiori rotundato; latere postico paululum extenso; super- ficie radiatim costata, costellarum lateribus superne angulatis, costellis anticis obsolete granosis; serie dentium cardinis angusta, postice recurva. Distinguished from A. grandis by its form, which is much more rounded at the inferior margin; by the angularity of its radiating ribs, which are moreover rather more numerous ; and by the narrow- ness of the lme formed by the row of hinge-teeth, and the recurved posterior termination of the same row. ARCA CONSOBRINA. PL. X. fig. 12. Testa oblonga, obliqua, zequivalvis, radiatim costata, lateribus superne angulatis, antico infra rotundato, postico rotundato-angulato; costis angustis, numerosis, plerumque quadratis, et decussatis, ad basin sulco tenui divisis, posticis fere levibus, planulatis; area cardinali latiuscula. In general appearance this resembles 4. labiosa ; the cardinal area is, however, much larger, and the ribs, except some of the posterior, are decussated. Judging from a cast, the two valves appear to be equal. PrEcteN THETIDIS. Testa orbicularis, tumida, radiatim costata, costarum marginibus quadratis, ad utrumque latus squamuliferis, squamulis minutissimis, interstitiis rugulosis ; auribus ineequalibus, radiatim costatis, costellis squamulosis. PECTEN INZQUALIS. Testa suborbicularis, tumidiuscula, costellis radiantibus 19, rotundatis, levibus, subdistantibus, superne lineis decussantibus hic illic sparsim notatis; interstitiis rotundatis, levibus, zquidistantibus; alterius valve costellis angustioribus in- terstitiis latioribus, leevissimis; auribus inequalibus, radiatim costellatis. PECTEN OXYGONUM. Testa suborbicularis, subobliqua, tumida, costellis radiantibus 19, superne acutan- gulis, interstitiisque equalibus lineis incrementi concinne decussatis; auribus - inequalibus, levibus, radiatim costellatis, costellis tenuissimis. Hi, AN\y ww \ . Quart. Geol. Journ. Vol. VI. FULk. Losstls strom San Domingo . ST De CSowerb vy fect a9 ¥ a 7 @uart. Geol. Journ. Vol. VI PIX. Fossils trom. San Domingo. S Le L Sowerby fectt. 1849. | NICOL ON THE SOUTH-EAST OF SCOTLAND. 53 PECTUNCULUS AcuTICosTATUS. PL. X. fig. 13. Testa suborbicularis, subobliqua, postice subangulata, radiatim multicostata, costis tenuibus, sulcisque angulatis; area cardinali bifariam tenuiter sulcaté, dentibus cardinalibus ad utrumque latus numerosis, confertis. A small species, distinguished by its subangular form posteriorly, its angular radiating ribs, and its numerous close-set hinge-teeth. It approaches in general form to P. Pallium, Reeve. Ostrea HAItTeEnsis. Testa oblonga, crassa, plicata, plicis paucis (senis ad septenis), magnis, undula- tis, subsquamosis, squamis nonnunquam subtubulosis; limbo interno omnino glabro. This species appears to be related to O. wmbricata, Lam.; it dif- fers, however, in its general form, which is oblong and not orbicular, and in the number of external radiating folds, which are only six or seven in our shell. SPONDYLUS BIFRONS. Testa subregularis, rotundata, ventricosa, margine latiusculo, valide denticulato ; extus radiatim costata, costis 5 ad 6 spiniferis; area cardinali alterius valve angustissima, alterius latiori. Nearest to S. imperialis, easily distinguishable by the area of one valve being very narrow, and that of the other being rather broader, though still narrow. 2. Observations on the Silurian Strata of the Soutu-East of Scor- LAND. By James Nicot, F.R.S.E., F.G.S., Assistant-Secretary Geol. Soc. DvuRiné a visit to the south of Scotland last autumn I collected some fossils from the older rocks of that district, which appear interesting as adding another link to the chain of evidence by which the true age of these deposits may be ascertained. Taken in connection with the fossils formerly noticed* and with those procured by Mr. Moore in Wigtonshire+, they may be regarded as rendering the Lower Silurian age of one part of these beds almost certain, so that the connection of the rocks and mountain-chains of this portion of Britain with those of other countries may now be so far traced out. The fossils which Mr. Salter last year kindly determined were chiefly procured from the only bed of limestone known in the Silurian rocks of the south-east of Scotland. My hopes of obtaining better or more characteristic specimens from that locality were disappointed, and not even a single new form was discovered after a careful search. Indeed, the highly crystalline texture of the limestone, probably oc- casioned by a mass of trap with which it is always associated, renders it very improbable that this bed will ever add much to our knowledge of the beings existing in the seas in which it was deposited. My researches in the slate rocks were more successful, especially in the Grieston quarry near Traquair. In this place the rocks consist of clay-slate, sometimes passing into a fine greywacke, and are wrought * Quart. Geol. Journ. vol. iv. p. 205. + Ib. vol. v. p. 7. 34 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, for a coarse kind of roofing-slate. The strata are thin and very re- gular, and dip at 65° to N. 51° W. of true direction. No cleavage appears in these beds, and the slates are formed by splitting the mass along the laminze of deposition, as the position of the fossils clearly proves. The rock is intersected by two sets of open fissures, of which one series dip at 85° to W. 45° S.; and another at the same angle to E. 5° N. The amount of dip and the direction vary considerably in both, the second being more irregular ; the edges of the beds along it are also broken, rubbed and striated, as if the masses of slate had been pushed over each other. The surfaces of some of the beds are very curiously marked, as the specimens on the table will show. Some of these resemble the ripple-mark common on sandstones, and others are not unlike the impression of some organic body, but the whole are more probably concretionary and entirely mineral in character. In some beds, concretions partly calcareous, partly ferrugmous occur, the latter much resembling moss or decaying wood, but showing no trace of organization when examined by the microscope. A few feet above these graptolite beds there is a thin irregular layer from half an inch to two inches thick, of a granular rock containing fragments of steatite and mica of a pinchbeck brown colour. In this quarry at least two beds contaiming fossils occur. The upper one is a fine-grained greywacke, the surface of which is almost covered by the Graptolites Sedgwickii, but the specimens, from the nature of the stone, are rarely well-preserved. About ten feet lower a bed of slate has been lately opened containing fossils of this genus in great abundance, which are found not only on the surface, but also through a considerable thickness of the slate. This circumstance, taken im connexion with the finer materials of the matrix and the beautiful state of preservation of the imbedded fossils, shows that these have lived on the spot, whereas those in the higher bed have more probably been drifted to this place by a stronger current. About seventy to eighty feet higher a third bed containing graptolites is known, but as a slip intervenes, 1t may probably be one of those already mentioned. At least six species of graptolites occur in this locality, as enumerated in the following list :— | Graptolites Sedgwickii, Portlock. Graptolites convolutus, Hisinger. distans, Portlock. — ludensis, Murchison. tenuis, Portlock. griestoniensis, new species. The last seems very distinct from any species formerly described, and is well-characterized by the oblong form of its polyp-cells which are closely appressed to the axis. The first four of these species were found by Colonel Portlock in the Lower Silurian slates of Desertcreat in Tyrone ; and the third, G. tenuis, also by Mr. James Hall in the black slates of the Hudson River group of New York, which is con- sidered by Mr. Sharpe and others as the equivalent of the Lower Si- lurian deposits of England. The G. ludensis, though originally dis- covered by Sir Roderick Murchison* in a higher part of the series, extends down into the Llandeilo flags. The G. convolutus, first de- scribed by Hisinger from the clay-slates of Sweden, has been since * Silurian System, p. 694, pl. xxvi. fig. 1, la.--_ i 1849. ] NICOL ON THE SOUTH-EAST OF SCOTLAND. 59 found in Ireland. These new discoveries therefore form a very satis- factory confirmation of Mr. Salter’s identification of the trilobites and shells of the Wrae limestone with those of the Tyrone beds. The Grieston slates often contam small fragments of anthracite, and a considerable amount of this substance was found some years ago in the Cadon Bank, a hill about a mile distant, forming an irregular bed or vein among the greywacke strata. It is very impure, and burns with much difficulty, so that even after being exposed for some time to the flame of the blowpipe, the form of the mass is little altered. The strata in which it occurs have been much disturbed and affected by igneous action, being intersected in one place by a vein of amyg- daloidal greenstone, whilst the top of the hill is formed of red felspar porphyry. In the ashes of this anthracite I have observed tubular fibres under the microscope, so that no doubt can be entertained of its organic nature. It thus proves that plants existed even in these early periods, in sufficient abundance to produce thin beds or seams of coal. In the Grieston slates some markings occur which may have been algee, but the structure shown in the ashes of the anthracite would rather indicate a higher class of vegetation. About three miles to the north-east of the Grieston and nearly in the strike of the beds, I also succeeded in obtaining a few specimens of fossils. They were found on Torysknies, a hill belonging to that group, in which, as the map will show, igneous action has chiefly pre- vailed in this district; the felspar porphyries decreasmmg in amount with the distance from it. The summit of the hill is formed of por- phyry, but the declivities consist of hardened slates, often almost crystalline in texture and closely resembling clinkstone. They con- tai much iron, and seem so altered by the connected igneous rocks, that the preservation of fossils was very unexpected, and proves the extreme difficulty of destroying organic forms when they are once im- bedded in the solid stone. The discovery of these remains in the prolongation of the former strata, shows that the fossiliferous beds are probably persistent for considerable distances, and may thus aid us in working out the suc- cession of these accumulations. It was also interesting on another account. About 500 yards south of the Grieston slates, a bed of red felspar porphyryis seen running nearly parallel to the slates, and may be traced in the same position relative to their outcrop for about a mile westward. A similar rock occurs at intervals for nearly four miles in the same line, but seems to disappear with all the rocks of this class before reaching the valley of the Yarrow. On the east I have traced. this, or a similar vem, at short intervals, cropping out on the sides of the hills or in the beds of the streams to a point north of that where the graptolites occur : at this place, however, the vein appears to have divided into two beds about fifty yards apart. This vein seems thus continuous for nearly eight miles in one direction, and runs generally parallel to the strata. This parallelism is, however, not complete, as it is in one place to the south, in the other to the north of the fossili- ferous beds, and has therefore intersected them in the interval*. * A still stronger proof that some at least of these felspar rocks are not con- temporaneous with the strata, but truly injected masses or dykes, is furnished by 56 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, In Thornielee slate quarry in Selkirkshire, on the bank of the Tweed, about six miles below Grieston, a few specimens of two of the same species of graptolites were found. The beds here dip at 82° to S. 50° K., or in the opposite direction to those at the former place, and also lie considerably south of their strike, so that they may thus form merely the other side of an anticlinal axis. ‘They have, however, a different mineralogical aspect, being often of a brownish red colour, so that I am more inclined to consider them distinct. Besides the G. convolutus and the G. ludensis, there is probably a foliaceous spe- cies of this genus, which is not seen im the Grieston slates. In the latter also annelid impressions are rare, whereas in Thornielee quarry they are very abundant, thus strengthening the view that these two localities belong to distinct parts of the series. Some of these worm- like impressions much resemble the species figured in the ‘ Silurian System’ of Sir Roderick Murchison, and may even be identical ; but it is difficult to obtain certamty in regard to forms presenting so few well-defined characters, that even their animal nature may be doubted. The regularity of the folds, with the apparent impression of feet or setze on the margin, seem to show that they are organic, and rather an impression of the body of the animal itself than a mere trail left in the soft mud*. Similar fossils occur in the Tyrone beds, which, as Colonel Portlock states}, “‘ exhibit on their surfaces those markings like the stems of algze and the tortuous labyrinths of annelids, so common to indurated muddy or sandy strata.” 'They have also been observed in the older paleeozoic rocks of North America, and several, not unlike those from Scotland, are figured by Mr. Emmons from his so-called Taconic group. ‘Thus far they confirm the view now given of the age and connexion of these rocks; though as similar rude me- morials of extinct life occur in formations of every age, they perhaps rather indicate similarity of conditions during deposition than identity of agef. From the whole facts noticed in this and a former paper, there can be little doubt that the slates and greywackes of this part of Scotland belong to the Lower Silurian pericd, and are probably the equivalents of the Llandeilo flags of Wales. Judging from the specimens of the older Welsh rocks contained m the Museum of the Society, these several veins that intersect the strata at a considerable angle. Veins of this kind may be seen in Priesthope, though most of them in that locality conform to the bedding. A vein near the source of the Leithen with a direction to S. 50° E. by compass, whilst the strike of the strata is nearly from E. to W., also confirms this view. In amass of vertical, or nearly vertical strata, the line of least resistance to the escape of an igneous rock would of course be between the beds. * Some of these impressions penetrate a considerable thickness of the slate, even as much as one-fourth of aninch. This shows that the animal has rather lived in the mud than moved through it. The peculiar arrangement in the mass below might arise from the worm gradually raising its body towards the surface by a kind of undulating motion as the soft mud accumulated and deprived it of access to the water. ; + Geol. Report on Londonderry, p. 230. t Similar forms are common in rocks of the coal formation and the lias, and spe- cimens from both are preserved in the Museum of the Society. Sir Charles Lyell recently presented others from modern mud deposits in the Bay of Fundy. See Quart. Geol. Journ. vol. v. p. 344. 1849. | NICOL ON THE SOUTH-EAST OF SCOTLAND. 57 flags are also the most closely allied in mineral character to the Silu- rian formations of the region now considered. ‘The coarse white sili- ceous grits common among the Caradoc sandstones are unknown, so far as I have observed, among the old rocks in the south-east of Scot- land. The only beds that approximate to these grits in mineral aspect are some in the south of Roxburghshire, and thus in what is probably a newer part of the series (perbaps equivalents of some part of the upper Ludlow rocks?). The most importaat pecu- harity of the Welsh rocks, is the great abundance of organic life which they exhibit when compared with the few traces found in the north. They seem also.to differ somewhat in mineral composition, containing a much greater emount of felspathous and apparently vol- canic materials than are seen in the Scottish strata. Even mineral and metallic products are, with a few exceptions, rarer in the latter deposits ;—probably consequences or at least indications of a less fre- quent contemporaneous igneous action. It is an interesting question how far we can connect the more or less abundance of life in these ancient seas with the variety of mineral ingredients thrown into their waters by volcanos existing at the time*. The Silurian beds discovered by Colonel Portlock in Tyrone, are, however, the nearest equivalents of those now described. The mineral characters of the rocks do not appear very different, and in both coun- tries they are characterized by the comparative scarcity of calcareous matter. The Irish strata also lie m the direct continuation of the northern part of the Scottish mountains, from the termination of which, near Portpatrick, they are only separated by an interval of 100 miles. From Peebles-shire the distance is nearly 200 miles, and the agreement in organic remains is perhaps closer than might have been expected, more especially as not more than three of the Peebles-shire fossils appear among those collected by Mr. Moore in an intermediate locality. It is also worthy of notice, that whilst the Grieston graptolites have only serratures on one side of the axis, those from Wigtonshire generally show these on both sides: hence the latter probably belong to another part of the series, and perhaps correspond with the patch of Silurian schists discovered in Fermanagh in Ireland, which contain the G. pristis and other foliaceous species like those in Wigton. These strata lie further south than the Tyrone beds with which the Peebles- shire deposits have most affinity, and Colonel Portlock+ also places them in a higher part of the series. In both countries therefore, the older rocks occur on the north, the newer on the south, a coimcidence confirming the classification of the Scottish deposits here proposed. In another point, the geological history of the two districts also cor- * The contemporaneous traps of the English Silurian deposits are described by Sir R. I. Murchison in his great work on this formation. See Silurian System, pp- 75, 269, 401, &c.; comp. Journ. Geol. Soc. vol. iii. p. 171-175. In this place the author ascribes the comparative rarity of animal life in certain portions of the English strata, to the inteuse igneous action which accompanied their deposition. The opposition to the view in the text is only apparent, as the eruptions which in their immediate vicinity and during the time of their most violent action were sufficient to destroy life, might yet be favourable to its development during the in- tervals of repose and at greater distances, by introducing more calcareous and other substances into the water. + Report on Lond. p. 232. 58 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, responds. Colonel Portlock draws attention to the strongly marked line of demarcation between the fauna of the ancient rocks in this part of Ireland and that of the formations which succeed them. “In fact,” he says, “there is here no such intermediate formation, in a fossil sense, as the Devonian system ; that is, there is no formation in which fossils peculiar to itself are commingled with a large percentage of those belonging to the Silurian on the one hand, and the carboni- ferous on the other*.”? And this may with equal truth be asserted of the south of Scotland, where the break both physical and paleeon- tological, between the Silurian and the next higher formation, is re- markably distinct, and indicates a long period during which no depo- sits have been here formed. It was probably during this interval that the rich ichthyolitic beds of Perthshire, Forfarshire and the north of Scotland were accumulated. It is in the latter localities therefore that a transition downwards from the well-known carboniferous and old red sandstone forms of life into those of the Silurian beds must be sought, rather than on the southern side of the synclinal trough. Any estimate of the thickness of these Silurian deposits must evi- dently be very imperfect, as the thick covering of detritus renders it almost impossible to work out continuous sections. The difficulty is increased by the principal rivers flowing generally along the strike of the beds, so that those transverse gorges in which full displays of the stratification might be expected to occur are very rare. The follow- ing calculations, therefore, are merely hypothetical, and intended rather to stimulate than to satisfy inquiry. Assuming that the Thornielee slates belong to a different part of the series from those of the Grieston, we have in this part of Scotland three distinct bands of fossiliferous rocks running from south-west to north-east in nearly parallel limes. The most northerly is the Wrae limestone, which, ina country where lime is of so much value, we may well believe would have been known had it again cropped out to the south. It can be cer- tainly traced for more than a mile, having been quarried on the south side of the Tweed near Drumelzier Castle, where it is also accom- panied by trap. A similar trap rock is seen twelve miles east in the Eddleston river associated with an impure limestone formerly quarried, which probably forms the continuation of this bed. The distance of these three bands from each other, measured on the map, at night angles to their strike, is six miles from the first to the second, and four miles from the second to the third, or ten miles in all. Allow- ing for the inclination of the strata, supposed to dip at an average angle of 50°, which is much below the reality, the beds included in these two zones will have a thickness of about 40,000 feet, or of 24,000 feet in the more northern one alone. As this is exclusive of the whole mass of more recent beds on the south, the Silurian for- mations of Scotland at least equal those of other countries in the amount of accumulations, however inferior they may be in abundance of organic remains. * Report on Lond. p. 233. + The “enormous aggregate thickness of the former deposits” was noticed twenty years ago by Prof. Sedgwick and Sir R. I. Murchison. See Trans. Geol. Soc., 2nd Series, vol. iii. p. 141. 1849. | NICOL ON THE SOUTH-EAST OF SCOTLAND. o9 In his Note on the most ancient systems of mountains in Kurope*, M. Elie de Beaumont includes the southern mountains of Scotland in his Westmoreland and Hundsriick system, though with some hesi- tation from uncertainty as to the age of the strata and their mean direction. The former difficulty may now be regarded as removed by the fossils collected by Mr. Moore and myself in such distant parts of the chain, and it thus seems worth while to inquire how far the general direction of the beds coincides with that which he assigns to this system. Among a large number of observations in Peebles-shire and the neighbouring counties, only sixty-six were sufficiently precise to be used for this purpose. With two exceptions, probably acci- dental, the whole of these fall in an are of 65°, or little more than one-third the circle. Thirty-five or more than a half dip to the north, thirteen or one-fifth are‘vertical, and the remainder, eighteen in number, dip south, as shown in fig. 1, in which the Roman numerals mark the number of beds, when more than one, corresponding to each line. The mean of the whole is E. 35° 10' N., or about 9° north of the mag- netic east. According to M. E. de Beaumont’s calculation, the di- rection of the system, to which he refers this chain, is in this place Fig. 1.—Direction of Silurian Strata in the South-East of Scotland. True North Variation 26°2 W. * Bulletin de la Soc. Géol. de France, tom. iv. p. 917. 60 PROCEEDINGS OF THE GEOLOGICAL society. [May 16 about E. 40° N., differmg 5° from the mean of the observations. He also ascribes the upheaval of the Grampians to the same great con- vulsion ; and it is remarkable that the narrow zone of clay-slate, ex- tending from Stonehaven to Arran, has for the greater part of its course a direction of E. 36° N., almost identical with the mean of the observations in the south. This band of slate may thus form the con- tinuation of the Silurian beds on the south, rising up on the other side of the synclinal valley in which the carboniferous strata of Scotland have been deposited. The mineral character of the rocks is not op- posed to this view ; and though no fossils are known in the northern slates, yet in Glen Halmidel in Arran I found spheroidal bodies similar to some very common in Peebles-shire, and which are pro- bably organic, perhaps casts of a species of trilobite. The direction of these chains is thus not very different from that which the theory would require. The elevation of this system is placed by the distinguished author in the interval between the close of the Silurian and the commencement of the old red sandstone de- posits. The latter were formerly * shown to rest unconformably on the edges of the upturned Silurian strata, and also to fill valleys ex- cavated in them subsequent to their elevation. This would carry back the formation of the chain to a period much anterior to the deposition of the sandstone; but as this rock in the south of Scotland should perhaps be rather associated with the carboniferous than with the true Devonian beds of England, an interval of sufficient duration for the various changes, which the strata have evidently undergone before they were covered up by the superior beds, may thus be obtained. But although the general direction of the strata and the period of their formation do not differ much from that required, there are other facts in the physical structure of this part of Scotland less fa- vourable to this ingenious theory. The Pentland hills, which have undoubtedly been formed subsequent to the deposition of the old red sandstone, or rather of the coal-measures, have a direction of E. 40°N., thus agreeing exactly with the line assigned to the Westmoreland system. ‘The same direction is reproduced in many of the ridges in the coal-field of the Lothians, and also in the trap rocks of Fife and the Ochils. In these instances we have parallelism of direction with- out identity of age. On the other hand, the Cheviots on the south probably coincide in age with the Pentlands, and also in their general direction ; but the porphyry rocks constituting their eastern and highest portion form ridges running N.N.E., and thus vary much from the direction of the chain of which they form a chief part, and also from the system of the North of England, with which they should be closely related in time. The structure of this part of Scot- land thus confirms the objections to this theory which Sir Henry de la Beche long ago derived from the lines of elevation observed in the south of England+. * Quart. Journ. Geol. Soc. vol. iv. p. 199. + Geol. Manual, 3rd edit. p. 489. M.E.de Beaumont indeed states that there . is a tendency in the older lines of elevation to influence the more recent elevations in their vicinity. This, however, so far from removing the objection, admits its truth, and consequently that parallelism in direction, even in neighbouring moun- tain-chains, is no proof of identity in the time of their elevation. 1849. | NICOL ON THE SOUTH-EAST OF SCOTLAND. 61 When we contrast the decided unconformity that always appears in Scotland between the Silurian strata and the formations that rest on them, with the perfect parallelism which has been shown to exist*, in the typical region, between deposits of the same age and the over- lying old red and carboniferous rocks, the argument becomes still stronger. With such proofs that these ancient disturbances are merely local, and have not affected all the rocks of one age even in the same couutry or limited district, we can hardly be expected to believe that their influence has extended over the whole of Kurope, and even into the more distant regions of Asia and America. The dip of the strata mm this range of mountains is far less regular, either in amount or direction, than their line of strike. On laying down, however, my observations on the map, it appears that towards the northern margin of the Silurian rocks, the dip is generally north- wards, whereas as we proceed south a change takes place, and the dip is more frequently to the south. Though there are numerous ex- ceptions, still this fact indicates the occurrence in this part of the chain of an anticlinal axis over which the beds have been folded. Taken generally, this axis will pass from the group of felspar porphyry hills east of Inverleithen to Loch Skene north of Moffat, where igneous rocks also abound. It thus runs along some of the highest mountains south of the Forth ; and the mineral springs at the localities just named are probably connected with this line of ancient igneous action. Its general direction is considerably more to the north of east than the average deduced for the strata. The position of this axis of elevation so near the northern boundary of the Silurian rocks is a point of much interest, from its apparent connexion with some of the most remarkable physical peculiarities of the country. On examining a geological map of Scotland it will be seen that the boundary between the red sandstone and the Silurian formations on the south is very irregular, the newer deposits forming many indentations in the older. It was thence inferred that the red sandstone had been deposited in valleys eroded in the greywacke rocks at a very early period+. The northern margin presents a different outline. The border there is for great distances nearly a straight line, with few sinuosities. Thus from the trap hills at the sources of the Nith, the line of junction runs almost direct to Howgate near Penny- cuik, where it bends shghtly to the south, but soon resumes a recti- linear direction towards the north-east to the coast at Dunglass, where it again curves round to the south. Along this line, especially to- wards the east, the junction of the two formations is marked by a range of hills composed of highly inclined Silurian strata, against which the red sandstone and carboniferous rocks abut in nearly hori- zontal beds. In some places this appearance is concealed by the igneous formations, especially those connected with Tinto and the Pentlands, but to the south of Edinburgh and along the base of the Lammermuirs it 1s very distinctly marked. In many_places the close * See Murchison’s Silurian System, chap. xlii. p. 568, &c., where the incon- sistency of this fact with the theory of M. E. de Beaumont is very clearly ex- - plained. T Journ. of Geol. Soc. vol. iv. p. 200. 62 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, resemblance of the steep slope of the greywacke hills to a sea cliff, somewhat softened by degradation in the long lapse of ages, can scarcely be overlooked by the most careless observer. And such, I believe, has been the origin of the peculiar features of this boundary-line. The Silurian strata evidently extend much farther north below the more recent deposits than their boundary on the map. This is proved by the fragments, covered unconformably by the old conglomerates and sandstones, which are exposed at several points in the Pentland hills where the deeper masses have been forced up by the igneous rocks in that chain. Such an extension of the Silurian beds is also required to balance, as it were, the southern side of the anticlinal arch, stretching down to the border of England. Hence I conclude, that whilst the southern half of the greywacke rocks was being cut into valleys by river action, the northern margin was ex- posed to the wasting influence of an open sea, which has planed down that rocky bed on which the newer formations of the central trough of Scotland have been deposited. It has only been near the conclu- sion of the Devonian period that conditions were again established in the southern part of the central valley of Scotland* permitting detritus to accumulate round the ancient shores. This accumulation has then gone on continuously durimg the whole carboniferous period—red sandstones passing gradually into white, these becoming mixed with shales and then with limestones, as the waters freed from the iron- peroxide became more favourable to the growth of corals and crinoids. Later the calcareous deposits decrease in abundance, and shales and sandstones alternate with seams of coal. During this period the land must have been alternately above and below water, the upright trees seen in many places having grown during the former; the large trunks, forty feet long or more, exposed im the sandstone quarries near Edin- burgh, having been drifted into the basin during the intervals of sub- mergence. The influence of these ancient revolutions on the actual physical geography of the country, particularly the direction of river drainage, deserves notice. On drawing a line along the watershed of the moun- tain chain, separating the rivers that flow south from those that reach the sea on the north of the axis, it is seen that the latter are compa- ratively insignificant. The division-line falls either very near, or even beyond, the northern boundary of the chain and of the Silurian rocks. Many of the streams that rise in the newer formations of the central district intersect the whole mass of older deposits on their way to the sea. Thus the Nith has its source in the coal formation of Ayrshire, within twelve miles of the Firth of Clyde, but turns south and falls into the Solway, after passing through the whole ridge of Silurian mountains, elevated in many points from 2000 to 3000 feet above the sea. Further west, some of the smaller streams, as the Cree and Ken, illustrate the same peculiarity ; and on the east, the Lyne and other * On the north side of this trough or valley, in Perth, Forfar, and Kincardine shires, these deposits have begun much earlier. This is shown by the great ex- tent of the old red sandstone in these counties compared to its limited develop- ment in Ayrshire and the Lothians. 1849. | NICOL ON THE SOUTH-EAST OF SCOTLAND. 63 tributaries of the Tweed follow a course apparently no less devious. The Clyde alone pursues an opposite direction, but many physical pheenomena show that its upper waters formerly joined the Tweed by the low valley near Biggar, and hence even this exception is of mo- dern date, and consequent on some of the most recent revolutions in this district. ‘Thus almost the entire drainage of this mountain-chain flows to one side, so that all its larger river-basins open out to the south. The greater number too of the most elevated mountain-sum- mits range along the northern margin, whilst on the south there are many low hills and undulating ridges. Hence the southern valleys are wider and blend more gradually with the plains than those on the north, where the streams often flow through narrow ravines, or deep notches, cut, as it were, in the steep wall of rock forming the ancient sea cliff. The Gladhouse south of Edinburgh, the Herriot near Dunglass, and the singular ravine crossed by the Peas Bridge at a height of 123 feet, but in other places 150 feet deep and only 50 broad, are good illustrations of this peculiarity. The line of coast south of Dunglass, where Hutton, Playfair and _ Hall found many of the most convincing illustrations of those great principles of physical geology which they laboured to establish, still exhibits many remarkable traces of this old Silurian beach-line. From the rocky promontory of Fast Castle, the coast trends westward in a series of bold cliffs, fenced by large fragments and outlying points of greywacke. Near Fala-bank it bends more to the north, and the red sandstone appears on the shore, dipping north-east at 25°, and folded in flat curves round the projecting masses of nearly vertical Silurian strata that project at intervals. The sandstone apparently retains its original position, the dip being due to deposition on a sloping bottom, and not to elevation ; and hence, in following the beds along the coast, they become more and more nearly horizontal. It is highly interesting to observe the sea gradually washing away the sandstone and exposing the ancient beach on which its waves beat so many ages before. Notes on the Fossils. GRAPTOLITES GRIESTONIENSIS. Fig. 2. I have given this name to the new species from the locality where it occurs. The characters mentioned above, ‘‘the oblong serratures closely appressed t0 e=nmenmen=enasoesssomemsss=nucss the stalk,” readily distinguish it from any other I have seen described. Each of these serratures has a raised margin dividing it from the axis and from the one that succeeds it upwards. The serratures and axis are about equal in breadth, and together measure 3, inch or under. The length of some fragments is 6 to 8 inches. In fig. 2, a is the natural size; 6, magnified. Solas 64 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 16, GRAPTOLITES CONVOLUTUS, Hisinger. Tn some specimens, probably young, the axis is very narrow com- pared to the length of the serrations, being little more than a mere line. In other specimens the axis becomes broader and shows a de- pressed line along the middle. This relative thickening and increase of the axis with age has already been noticed by Geinitz*. In some, perhaps very oid varieties of this species, the axis is much less curved, and the serratures much shorter. They form merely a series of very obtuse and wide teeth, scarcely projecting beyond the margin. This may form a distinct species; but the variations evidently produced by age, or from the manner of imbedding in the stone, as seen im differ- ent parts of the same specimen, show that much caution is required in such distinctions. GRAPTOLITES LUDENsIS, Murchison. The specimens agree very well with the figure given in the ‘Silurian Systemt.’ The most important difference is m the more rounded, almost club-shaped form of the ends of the serratures in the fossils from Peebles-shire. This probably arises from the specimens being in a more perfect state of preservation. In some of the larger speci- mens both of this species and of the G. Sedgwickii, Portlock, the stem near the root is narrow and almost destitute of serratures, but becomes broader and the serratures very distmct as it ascends. Where also the back of the specimen only is exposed, the serratures may be wholly concealed, so that it appears entirely destitute of these appendages, and such a fragment might readily be taken for a new species. Where the opposite side again is turned to the spectator the serratures are pressed flat, and appear like broad lobes divided by narrow depressions, giving the stalk a jomted appearance. Where the back is well-seen, it is marked by a fine groove running along its centre. Some of our specimens are fiom 10 to 12 inches long, though imperfect at both ends. GRAPTOLITES LAXUS. The foliaceous species from Thornielee, mentioned above, some- what resembles the G. pristis, Hisinger, but the axis is much nar- rower, and the serratures longer in ropes to their breadth (or length to breadth rather more than 2:1). They are also separated by an interval equal to their own width, or even more, a character not seen in any other foliaceous species figured. In this respect it differs so much from the general aspect of the genus, and so closely resem- bles some plants of the moss-tribe (Hypnum), as to render its real character doubtful. Ifa true graptolite, it seems undoubtedly a new * Leonhard and Bronn’s Jahrbuch fir 1842, p.701. The G. spiralis of Geinitz seems identical with the G. convolutus, Hisinger. 7 Plate 26, figs. 1 andla. In this work the importance of these fossils, as distinguishing different parts of the Silurian formations, was first made known to geologists. See pp. 206, 694. 1849. ] MURCHISON ON THE DETRITUS OF THE ALPS. 65 species, to which the above name may be given from its most remark- able character. The true nature of these remains seems still rather uncertain. Schlotheim described them as Orthoceratites, and in his figure a central siphon is represented, and the stem seems composed of di- stinct cups or joints*. No indication of either of these characters is seen in the most perfect of our specimens, so that we almost doubt whether his fossil belongs to the same class. Other geologists have described them as fucoids. In the ‘Silurian System’ they are classed as Polyparia, which seems now the opinion generally received. Some of our specimens have left merely a dark, perhaps carbonaceous im- pression on the slate ; others show a cartilaginous or horny texture. In several specimens the slate is discoloured for some distance on each side, and shows minute scales of carbonate of lime, as if the more perishable parts of the animal had extended thus far. It is thus doubtful whether these remains have all belonged to animals of one class ; and whether some of them may not rather have been internal organs, than the external axis of a variety of polypifer ? May 30, 1849. P. Martin Duncan, Esq., M.D., and J. Lane Oldham, Esq., were elected Fellows of the Society. The following communication was then read :—- On the Distribution of the Superficial Detritus of the Ars, as com- pared with that of NorTHERN Europe. By Sir Roperick Impry Murcuarson, F.R.S. G.S. L.8., Hon. Mem. B.S. Ed., R.1. Ac., Mem. Imp. Ac. Sc. St. Pet., Corr. Mem. Ac. France, Berlin, Turin, &c. Xe. [ABSTRACT. | REFERRING to his previous memoir upon the structure of the Alps and the changes which those mountains underwent, the author calls attention to the fact, that as during the formation of the molasse and nagelflue a warmer climate prevailed, so after the upheaval of those rocks an entire change took place, as proved by the uplifted edges of such tertiary accumulations bemg surmounted by vast masses of horizontally-stratified alluvia, the forms of whose materials testify that they were deposited under water. The warm period, in short, had passed away and the pine had replaced the palm upon the adjacent lands, before a glacier was formed in the Alps or a single erratic block was translated. Though awarding great praise to the labours of Venetz, Charpen- tier and Agassiz, which have shed much light on glaciers, and par- ticularly to the work of Forbes for clearly expounding the laws which * Petrefactenkunde, Nachtrage, p. 56, tab. 8. fig. 3. VOL. VI.—PART I. F 66 PROCEEDINGS OF THE GEOLOGICAL Society. [May 30, regulate their movement, Sir Roderick conceives, that the physical phenomena of the Alps and Jura compel the geologist to restrict the former extension of the Alpime glaciers within infinitely less bounds than have been assigned to them by those authors. True old glacier moraines may, he thinks, be always distin- guished, on the one hand, from the ancient alluvia, and on the other from tumultuous accumulations of gravel, boulders and far- transported erratic blocks, as well as from all other subsequent detritus resulting from various causes which have affected the surface. He first shows, from the remnants of the old water-worn alluvia which rise to considerable heights on the sides of the valleys, that mm the earliest period of the formation of the Alpine glaciers, water, whether salt, brackish or fresh, entered far into the recesses of these moun- tains, which were then at a considerably lower level, 7. e. not less, per- haps, than 2500 or 3000 feet below their present altitude. He next appeals to the existing evidences in the range of Mont Blanc to show, that as each glacier is formed in a transverse upper depression, and is separated from its icy neighbour by an intervening ridge, so by their movement such separate glaciers have always pro- truded their moraines across the adjacent longitudinal valleys into which they descended—and never united to form one grand stream of ice in the valley below. To prove this, it is affirmed that there are no traces of lateral moraines on the sides of the adjacent main valleys, whether on the side of the great ridge from whence the separate glaciers issued or on the opposite side of such main valley, which must have been the case if a large mass of glacier ice had ever de- scended it. On the contrary, examples of the transport of moraines and blocks across such main or longitudinal depressions are cited from the valley of Chamonix on the one flank and from the Allée Blanche and Val Ferret on the other or south side of the chain of Mont Blane. Another proof is seen in the ancient moraine of the Glacier Neuva, the uppermost of the vailey of the Drance ; and a still stronger case is the great chaotic pile of protogine blocks accumulated on the Plan y Boeuf, 5800 French feet above the sea, which have evidently been translated right across the present deep valley of the Drance, from the opposite lofty glacier of Salenon. Having thus shown that not even the upper longitudinal and flank- ing valleys around Mont Blanc were ever filled with general ice- streams, the author has no difficulty in demonstrating that all the great trunk or lower valleys of the Arve, the Doire, and the Rhone, offer no vestiges of what he calls a true moraine; since although they contain occasional large erratic blocks, for the most part irregularly dispersed, all the other detritus is more or less water-worn, to great heights above their present bottoms. As Venetz and Charpentier have attached great importance to the original suggestion of an old peasant of the Upper Vallais, that a great former glacier alone could have carried the erratic blocks to the sides of the lower valley of the Rhone, so on the other hand the author, if he had had any doubt himself, would have relied on the practised eye of his intelligent Chamonix guide Auguste Balmat, who never recognized the remains 1849. | MURCHISON ON THE DETRITUS OF THE ALPS. 67 of “moraines”’ in that detritus of the larger valleys which has been theoretically referred to old glacier action. In descending from the higher Alps into the main or trunk valleys, Sir Roderick found many examples of rocks rounded on that side which had been exposed to the passage of boulders and pebbles, with abrupt faces on the side removed from the agent of denudation, all of them reminding him forcibly of the storm and lee sides of the Swedish rocks over which similar water-worn materials have passed. Seeing, then, that this coarse drift or water-worn detritus is dis- tributed sometimes on the hard rocks and often on the remnants of the old valley alluvia, he believes that the whole of the phenomena can be explaimed by supposing that the Alps, Jura, and all the sur- rounding tracts have undergone great and unequal elevations since the period of the formation of the earliest glaciers— elevations which, dislodging vast portions of those bodies, floated away many huge blocks in ice rafts, down straits then occupied by water, and also hurled on vast turbid accumulations of boulders, sand and gravel. To these operations he attributes the purging of the Alpine valleys of the great mass of their ancient alluvia, and also the conversion of glacier moraines into shingle and boulders. He denies that the famous blocks of Monthey opposite Bex, can ever have been a portion of the left lateral moraine of a glacier which occupied the whole of the deep valley of the Rhine,—as Charpentier has endeavoured to show ; and he contends that if such had been the case they would have been associated with numberless smaller and larger fragments of all the rocks which form the sides of the valley through which such glaciers must have passed. They are, however, exclusively composed of the granite of Mont Blanc; and must therefore, he thinks, have been transported by ice rafts,—which, having been forced with great violence through the gorge of St. Maurice, served to produce many of the strize which are there so visible on the surface of the lime- stone*. Fully admittmg that the stones and sand of the moraines of modern glaciers scratch, groove, and polish rocks, Sir Roderick Murchison still adheres to the idea he has long entertained from surveys in Northern Europey, that other agents more or less sub- aquecus, including icebergs and heavy masses of drift, have produced precisely similar results. He cites examples in the Alps, where perfectly water-worn or rounded gravel being removed, the subjacent rocks are found to be striated im the directions in which such gravel has been moved ; and he quotes a case in the gorge of the Tamina, * Mr. Charles Darwin, in a recent letter to the author, adheres to his old opinions on this point, derived from observations in America, and says, “ I feel most entirely convinced that floating ice and glaciers produce effects so similar, that at present there is, in many cases, no means of distinguishing which formerly was the agent in scoring and polishing rocks. This difficulty of distinguishing the two actions struck me much in the lower paris of the Welsh valleys.” + See Silurian System, pp. 509 to 547; Russia in Europe and the Ural Moun- tains, vol.i. pp. 507 to 559 ; Presidential Discourses, Proc. Geol. Soc. Lond. vol. iii. p. 671, and vol. iv. p.93; Journ. of Geol. Soc. Lond. vol. ii. p. 349; and Trans. R. Geol. Soc. Cor.:wall, vol. vi. . F 2 68 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 30, above the Baths of Pfeffers, where this ancient striation, undistin- guishable from that caused by existing glaciers, has, by a very recent slide of a heavy mass of gravel from the upper slope of the same rock, been crossed by fresh scorings and striee, transverse to those of former date, from which the markings made in the preceding year only differ in being less deeply engraved. He also adverts to the choking up of some valleys, particularly of the Vorder or Upper Rhine below Dissentis, by the fracture, in situ, of mountains of limestone, which constitute masses of enormous thickness, made up of innumera- ble small fragments, all of which have been heaped together since the dispersion of the erratic blocks; and he further indicates the effects of certain great slides or subsidences within the historic era. In considering the distribution of the erratic detritus of the Rhone, the author having denied that it can ever have been carried down the chief valley to the Lake of Geneva in a solid glacier, he still more insists on the incredibility of such a vast body of ice having issued from that one narrow valley, as to have spread out over all the low country of the cantons Vaud, Friburg, Berne and Soleure, and to have protruded its erratics to the slopes of the Jura, over a region of about 100 miles in breadth from north-east to south-west, as laid down in the map of Charpentier. He maintains, that in the low and undu- lating region between the Alps and the Jura, the small debris derived from the former has everywhere been water-worn, and that there is in no place which he saw anything resembling a true moraine; and he therefore believes, that the great granitic blocks of Mont Blane were translated to the Jura by ice-floats, when the mtermediate country was under water. He further appeals to the water-worn condition of all the detritus of the high plateaux around Munich, 1600 and 1700 feet above the sea, to show that a subaqueous condition of things must be assumed, for the whole of the northern flanks of the Alps, when the great erratic blocks were carried to their present positions. Prof. Guyot of Neufchatel has endeavoured to show, that the de- tritus of the rocks of the right and left sides of the upper valley of the Rhone have also maintained their original relative positions in the great extra Alpine depression (Lake of Geneva), and that these re- lations are proofs, that nothing but asolid glacier could have arranged the blocks in such linear directions. But the author meets this ob- jection by suggesting that there are notable examples to the contrary. He also refers to the great trainées of similar blocks which preserve linear directions in Sweden and the low countries south of the Baltic, to show that as this pheenomenon was certainly there produced by power- ful streams of water, so may the Alpine detritus have been arranged by similar agency. In alluding to the drainage of the Isére, he further points to the admission of Prof. Guyot, that nearly all its erratic de- tritus, both large and small, is rounded and has undergone great at- trition ; and he quotes a number of cases in which such boulders and gravel, derived from the central ridges of Mont Blanc, have been transported across tracts now consisting of lofty ridges of limestone with very deep intervening valleys; and therefore he infers that the whole configuration of these lands has been since much changed, in- 1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 69 cluding the final excavations of the valleys and the translation of enormous masses of broken materials into the adjacent low countries of France. Tn conclusion, it is suggested, that the dispersion of the{far-travelle Alpine blocks is a very ancient phenomenon in reference to the historic zera, and must have been coeval with the spread of the northern or Scandinavian erratics, which it has been demonstrated was accomplished chiefly by floating ice, at a time when large portions of the Continent and of the British Isles were under the sea. Viewing it therefore as a subaqueous pheenomenon, Sir Roderick is of opinion that the transport of the Alpine blocks to the Jura falls strictly within the dominion of the geologist who treats of far bygone events, and cannot be exclusively reasoned upon by the meteorologist, who invokes a long series of years of sunless and moist summers to account for the production of gigantic glaciers upon land under present terrestrial conditions. This last hypothesis is, it is shown, at variance even with the physical phenomena in and around the Alps, whilst it is m entire antagonism to the much grander and clearly established distribution of the erratics of the North during the glacial period. The effect im each case is com- mensurate with the cause. The Scandinavian chain, from whence the blocks of northern Europe radiated, is of many times larger area than the Alps, and hence its blocks have spread over a much greater space. All the chief difficulties of the problem vanish when it is ad- mitted, that enormous changes of the level of the land in relation to the waters have taken place since the distribution of large erratics ; the great northern glacial continent having subsided, and the bottom of the sea further south having been elevated into dry land, whilst the Alps and Jura, formerly at lower levels, have been considerably and irregularly raised. JUNE 13, 1849. The following communication was read :— On the Valley of the ENGLIsH CHANNEL. By Rozerr A. C. Austen, Esq., F.R.S., F.G.S. Tue valley of the English Channel presents two points of geological interest which may be considered as new—the one relating to the nature of its bed, as a guide to the conditions of origin of our older marine formations; the other to its age as an area of depression. For the former purpose the area may appear to be too limited ; the extent of surface, however, from the Straits of Dover to the outward line of soundings, is more than equal to the whole of the South of England from the Land’s End to the Wash, an area which comprises the whole series of English geological formations. Having had frequent oppor- tunities of cruising about this Channel, I have been enabled, at one time or another, to visit nearly every portion of its shores on either side, and to examine its bed with the dredge and sounding-lead. 70 PROCEEDINGS OF THE GEOLOGICAL society. [June 13, The English Channel occupies a valley bounded by two parallel systems of elevation. The line of 49° 58', commencing from the east coast of France, near Dieppe, and which passes a little south of the Lizard Point, is as long a straight line as can be drawn within it. A physical area may have a general form and outline, which may not at all represent the direction of the forces by which it has been produced. The movements by which relief has been given to portions of the earth’s crust are seldom continuously linear; the lines themselves, taken separately, are constantly seen to diminish in amount m oppo- site directions, and to be arranged en échellon. Such is the case along the South of England; the accidents of the strata run east and west ; such is also the case in Lower Normandy and Brittany ; this is their true direction as areas of elevation, of which the Channel is the inter- vening depression: a central line along this area would have a general direction from E.N.E. to W.S.W.; in this imstance therefore the geological and geographical features are not parallel. Like mstances may be traced wherever long lines of elevation have been produced. A central line from the Straits of Dover across the German and North Seas would equally mislead us there; the true physical features of that depression are the straight north and south line of coast along the departments of the Somme and the Pas de Calais, the rocky masses of the Varne and the Ridge rising with steep sides from deep water ; the same line, if prolonged, will pass in front of the Goodwim Sand, along a trough having in places a depth of forty fathoms, and will define the coast of England from Orford Ness to Yarmouth. The direction of the troughs having thirty fathoms water are also parallel with this line. A series of transverse sections from the coast of England to that of France, drawn north and south, will show that the Channel area is one of depression. Im all such sections the sedimentary strata on either side have an inward dip. This position of all the secondary beds is familiar to most geologists, and hardly requires illustration. The east and west strike of the older strata to the west of the secon- dary formations is indicated on the map, and the like direction ob- tains throughout the paleeozoic groups of Brittany and Lower Nor- mandy. The lower valley of the Seme may probably be connected with the later disturbances of the Channel valley ; the lines of deepest water are along its south side, and will be shown to correspond with its original greatest depression: it is a common character of lmear undulations of the earth’s crust, that they break into fractures or faults at their extremities. The general direction of the valley of the Seine from Havre to Rouen is due east and west. The re- markable cliffs which occur at places along this valley have been described by Sir C. Lyell; they can hardly have been produced by the present river, nor is there any accumulation of shingle along its course to account for its occupation by the sea. The features are difficult of explanation, but it suggested itself to me when I last saw them, that they were the result of a fault traversing a mass of ele- yated strata, by which portions had been let down; a depression of the strata on one side corresponding with the vertical wall of the cliff 1849.]| AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 71 on the other, according to what is to be observed in every valley of fracture. Whether this supposition respecting the valley of the Seme be correct or not, we at least meet with features on our own coast which make it probable. ‘Thus, for instance, the vertical cliffs of the Watcombe fault have certainly been produced since the district existed in its present condition of dry land: the direction of this break is east and west. Again, Torbay, which is a portion of an east and west depression, has its recent age defined by the marine beds resting on the lines of elevation which bound it. So much has been written respecting the quantity of matter carried down annually to the sea by rivers, that many have been led to regard it as the main source of submarine sediment: the English Channel is perhaps as good an instance as could be taken of the fallacy of such a supposition. The Seine is the only river of any magnitude which discharges into it. Now rivers carry forward matter in two ways— by holding it in suspension, and by drifting it along their beds. The quantity of suspended matter im the estuary portion of such a river as the Seine is occasionally considerable; but it is an incon- siderable portion of this only which finds its way out to sea at each ebb; whilst the sands which are subject to the drifting process ac- cumulate in well-defined forms about its mouth. If we take the whole extent of the dry land drained by the rivers running into the English Channel, together with its mean elevation, we shall see that the whole of this mass, if removed down to the sea level, would be insufficient to fill up that depression. We may feel assured that the joint action of all the Channel rivers contributes but very little towards its accumulations. On comparing some old charts of the mouth of the Thames with the most recent ones, the principal feature in which they seemed to differ, was the present outward extension of the shoals and banks. Sir H. De la Beche has treated of the action of the sea along its coast-line in full detail ; it is this lme which furnishes the great mass of materials we find strewed over its beds. ‘To show that it is an adequate source, we have only to bear in mind, that in the instance of the area of the English Channel, if we follow its irregularities, we have an outline of not less than 1200 to 1300 miles, together with a great vertical range of tide. The removal of solid materials from the cliffs is not, however, so constant as some persons might imagine, not even on parts of the coast with yielding strata. There are very few places on our own side of the Channel, or on that of France, at which the sea at high-water regularly reaches the bases of the cliffs, and where it does so, from the hardness of the rocks, the rate of destruction is the slowest. As a general rule, it is only with high tides, concurrently with gales of wind setting on a given line of coast, that we see any considerable masses undermmed and thrown down. If this be the case in such a sea as the Channel, where the power of the breakers is exhibited on so vast a scale, it teaches us to require enormous lapses of time for the production of sedimentary strata of the thickness of some of those for which the geologist has to account. But though the sea for months together, and in places even for = /2 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 1 3 whole years, may not acquire any fresh spoil, yet there are very few hours when its waters are unemployed, in abrading and fashioning the materials already acquired. The zone of depth along which this process takes place is comparatively narrow; much of the gravel and shingle seems to travel up and down from the exposed beach to slight depths below; accumulation of sand may go on for a time, but a heavier sea soon disturbs this arrangement. The materials of long lines of beach may also be entirely swept away, and carried down into deeper water; in this way I have seen, at one time or another, nearly every portion of our south coast in the condition of bare rock without sand or shingle: the sea-bed has no permanent character over the first few fathoms of its depth. Bars, sand- and shingle- banks, belong to this zone, and these are likewise all subject to change of form and to removal, but they speedily collect again; and it is worthy of notice, as bearmg on conditions to be observed at greater depths, that every part of this zone preserves its distinct cha- racter—the banks which form again after a sweeping of the margmal zone are always of the same description as were collected there before. The materials composing shingle beaches clearly show that the ordinary action of the sea is at right angles to the coast-line, as they will I think invariably be found to have been derived from the con- tiguous cliffs. The line of flmt shingle along the French coast, at the eastern end of the Channel, is exactly conterminous with the chalk cliffs, and like facts may be seen carried out in the minutest detail along our own western shores, at places where limestone, trap, or granitic rocks occur. In this case the action is simply that of the tide. With this, however, there is an occasional tendency for the shingle to travel onwards in a given direction. ‘This movement has nothing whatever to do with the action of the tide; for as this in every channel makes in the offing before it does in-shore, its force, even if it was equal to such a process, is exerted at right angles, and not parallel with the coast. Along our own southern coasts the movement of the shingle is from west to east, and on the opposite coast of France it is the same. Wherever the direction of the wind coincides with the lme of coast, an onward movement is imparted to the marginal line of water, and this moves the shingle along with it ; thus the flint shingle from the chalk cliffs of the department of the Somme travels south, towards the mouth of the Seme, under the in- fluence of north and north-east winds. The easterly movement of the shingle along our own coast may be easily observed; and in order to show that the assumed cause is a sufficient one, it is only necessary to establish the fact, that along the Channel there is preva- lence of winds setting in the requisite direction. From the position of the Channel, any winds between north and south passing through the west, will act obliquely on the coast on one side or the other; and these up-channel winds are known greatly to preponderate over those which pass from north to south through the east. There is a peculiarity which has been observed with respect to the winds west of south, that they blow with most violence at the times of high tides, and particularly that they come in at the first of the 1849.| AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 73 flood. We have taken the line from Dieppe westward as the one which indicates the line of the Channel: it appears that at this place, according to a register kept by M. de Bréauté, extending over twelve years, that the direction of the wind was 135 days between south and west, and 94 days between west and north, or 229 days out of the 365 durimg which the materials along some part or other of the Channel might have an eastward movement. There are no observa- tions to guide us as to the rate at which the marginal line of shingle is made to travel forwards in this manner, but the distance at which it occurs from its point of origin is occasionally very great. On the Chesil beach may be collected pebbles of limestone, greenstone, trap, and old red sandstone, derived from the older rocks of South Devon. Much of the irregularity of the present outline of the Channel, where it is independent of other causes, is due to the nature of the beds which occur along it. Passing over minor examples, good illus- trations of this are to be seen in the deep bay between Berryhead and Portland, an interval which corresponds with that of certain yielding sands and marls; as also in the recess along the coast of Calvados. SY ; “jy AE Uppy. Good illustrations of the process of cutting back along the mar- ginal sea zone, and of the depth to which this action is carried in the case of hard compact beds, can be seen about the Channel Islands. Sections of some of these groups of rocks show that they rise off plat- forms, which have an uniform depth from the surface, and that from their edges there is a rapid fall to the general sea-bed below. The platform to the north of Ortach and Burhou comes nearly to the surface, so that the projecting poimts are uncovered : when the wind is fresh, the sea breaks violently on this platform ; the fall is immediate into 18 fathoms water. ‘Time being allowed, such a group as that of the Caskets (fig. 1) would ultimately disappear, and be reduced to a submarine shoal. Some of the actual shoals of these seas have pro- bably at some former time existed as small groups of rocks ;—that of the Pomier, two miles north-east of the Caskets, is apparently a good instance of a mass of rock reduced to its utmost with relation to the present sea-level. This shoal is a table-rock rising abruptly out of 170 feet water to within 36 feet of the surface, covered at top with patches of coarse sand and shingle, and, as usual, with a vast growth of sea-weed. Viewed in this way, the Channel Islands group, taken collectively, will present mstances of masses in every stage of abra- sion ; and judging from the soundings round the several shoals, rocks, and islands, the depths to which such masses may be reduced will range down to between 40 and 50 feet at the very utmost. | This process, by which masses of solid materials can be planed off | parallel with the sea-level, is due to the action of wind or surface | 74 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 13, waves, inasmuch as in calm weather, when I have had opportunities of passing over some of these platforms, I have felt convinced that the only other agent, namely the tidal streams, had not sufficient velocity to exercise any mechanical power whatever. With the present tendencies of geological speculations, it is of some interest to ascertain, if possible, the depths at which the sea- bed is liable to disturbance : on the determination depends the know- ledge we may some day acquire of the conditions of accumulation, which the older stratified deposits exhibit. Whenever a stream of water flows over a rocky or uneven bed, the interruption which the lower stratum experiences is indicated by a wave-disturbance at the surface: of this every running stream is a ready illustration. In parts of our seas, surfaces of broken water, known as races and overfalls, are constantly met with, and may even be observed from the land. The race of Portland occurs over a ledge of rock which runs out from the south extremity of the Bill; the east and west sides of this ledge are steep : the case of the St. Alban’s race is precisely similar. The surface-disturbance at these places is to be observed im the calmest weather, and in drifting over them at such times, the passage from smooth into broken water is immediate. In like manner the race of Barfleur, more formidable than either of the preceding, occurs over a ledge of rocks, running out from the headland of that name. As in all cases, the greatest disturbance, apart from the action of the wind, takes place at new and full moon, when the tide-stream flows with a velocity of from eight to nine miles an hour ; showing that the races are due to the arrest of the tidal stream by these ledges. The Boulogne fishermen sink their nets athwart the deeps at the east end of the Channel; should the weather become too rough to allow them to get them in, they are sure to recover them on the coast between Cape Gris Nez and Calais, whither the flood tide drifts them in. These and many like cases to be collected along the coast show that the tidal movement extends to the whole depth of water. These cases are to be observed along the marginal zone, and some persons have drawn a distinction between the movement of the tide in deep as compared with shallow water. A broken or rippled surface is met with at certain places in the open part of the Channel, as along the entrance from the Atlantic: these appearances are mm every instance connected with uneven ground below. ‘The ripplings over Jones’s Bank are very considerable ; the shoalest part of this bank has 40 fathoms, with a surrounding sea-bed at 70. A like surface dis- turbance is constant along the edge of the Nymph Bank, which has a minimum depth of 45 fathoms. The Little Sole Bank has like in- dications even in the calmest weather: over the summits of this group there is a depth of 60 fathoms, with 100 fathoms at short di- stances around. In all these imstances the place and extent of the ripplings depend on the direction and strength of the tide: the slopes of all these banks are steep; the process is the same as with the shallower ledges, and shows, according to what theory requires, that the tidal stream movement extends to the whole depth of the Channel. Tn the earliest accounts we have of the Channel and its dangers, we 1849.| AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 70) find notices of “races”’ as occurring at the very spots at which we now meet with them; tending to show, that whereas the action of breakers along the coast-line has, within comparatively short times, produced great changes, by the removal of thick masses of strata, yet that no corresponding abrasion has been effected over these ledges under depths of not more than 17 fathoms. The difference of velocity between the upper and lower strata of water put in motion by the tidal stream, as in every current, is less over the bed than at the surface; but the surface velocity, even in parts of the Channel where it is greatest, cannot be estimated at more than from five to six miles an hour, so that its movement over the ground or as a mechanical agent is very trifling. The two actions, first, that of wind-waves when they break in shallow water; and, secondly, that of the tidal stream, are alone en- gaged in fashioning and arranging the materials of the sea-bed *. The principal action of the wind-waves, as exercised on the land, is confined to a zone extending from one range of the tide to the other. In a zone below this, a certain amount of shiftmg, and consequent abrasion of the materials, may take place ; the breadth of this zone will depend on the nature of the coast, whether shelving or other- wise ; for with the deepening of the bed beyond the line of wave-un- dulation this direct littoral action ceases. It would be difficult to lay down the precise zone of depth along which the action of wind-waves may be considered to cease; but as in high waves of this order, at a depth equal to one-third of a wave-length, the range of oscillation of the particles is only one-thirtieth of that of the particles on the sur- face, the depth to which water can be affected in any part of the Channel cannot be very great. Where the action of the wind-waves ceases, the permanent influence of the tide-stream begins ; and as this extends to every depth and portion of the Channel, it has for its limits, as an agent of accumulation, only the length of time durmg which particles of matter may remain im suspension: in short, in every sea the power of abrasion is confined to a marginal zone, and that of dispersion, though with a wider range, extends only to the minuter particles of matter. I am aware that a very different view of the movement of the water of the Channel has recently been given, and that in support of it the areas of discoloured water over certain banks at great depths, as well * It is only proper to state, that M. Emey, who has treated the subject of the movement of the waters of the sea in great detail, so far as bars, sand- and shingle- banks, and even erratic blocks are concerned, attributes them to the action of what he terms his ground wave (flo¢t de fond) ; that is, to the motion of the water near the bottom towards the shore. (Mouvement des Ondes, p. 51.) M. Emey adduces, as practical tests of his theory, first, that when bathing in the sea, at a short distance from the shore, and with the body upright, we are lifted up by the surface-undulation, whilst at the same time the horizontal passage of the ground wave to the beach is felt by the legs. Again, if two pieces of cork, one weighted so as just to sink to the bottom, be thrown into the sea, the floating piece will keep its distance from the shore, and only follow the surface-undulation, ney the weighted one will be rolled along the bed, and thrown up on the each. 76 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 13, as rippled surfaces, have been used as proofs that to such depths the sea-bed may be disturbed by gales of wind. It may be asked, on the other hand, how is it, if the oscillation of wind-waves at certain places can reach down to the bottom so as to disturb the bed, they do not do so equally over those wide areas where the sea has an uniform depth of that amount? Against this too may be adduced the direct and important testimony of those persons who haye worked from the diving-apparatus, that with a fresh breeze and considerable surface- movement no disturbance was ever to be experienced below. Discoloration is at all times to be noticed over the banks im ques- tion, even when the sea is perfectly quiescent, as far as wind-waves are concerned: we know from soundings that these places are within the range of fine sedimentary deposits ; and with respect to matter falling through water slowly, we know, that at the distance of these banks from any land, it will be principally in the lower strata of water that the suspended matter will occur. The tidal current which has carried a column of water of 500 feet over a considerable space, on meeting one of these banks, is suddenly reduced to 300 feet. The effect of this is to produce that peculiar form of disturbance which resembles a boiling-up and flowing-off of the surface, and which is so characteristic of shoal disturbance im perfectly calm weather. By this process lower strata of water are forced up, and bring with them the finer particles which had reached those depths. The change in the colour of the water at these places is however very slight, bemg from blue to a pale disturbed green, and the quantity of suspended solid matter by which it is produced is exceedingly small. § 1. Distribution of Materials and Map of the Channel. As the coast-line is the only source whence the materials which compose the sea-bed are derived, and as the movement of the water, at inconsiderable depths even in advance of this line, is totally insuffi- cient to produce the forms and conditions of the materials which oe- cur there—the same also with respect to all subsequent outward zones of depth—the mass forming the sea-bed at every place must have travelled outwards. The coarser materials of several areas can be identified with the rocks on the coast from which they have been derived: thus granite and tin-stone shingle occur round the Land’s End and Scilly Islands, whilst the syenites and allied rocks of the Channel Islands group take a wide range on that side of the Channel. Tn addition to such instances as these, we have also the evidence from the shell-sand beds, which constitute such extensive areas In our Channel, and apparently in all seas; few if any of the shells whose fragments are so abundant over these areas belong to them, or have lived there: sharp sands, and such as can drift, are especially poor in submarine life, nor do we meet with any weed. The great pro- portion of these shelly materials has come from a contiguous higher zone; but mixed with these, and in considerable abundance, are the pounded fragments of the commonest littoral species; thus the Ha- liotis tuberculata, one of the peculiarities of the Brittany and Channel 1849.| AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 77 Island coast fauna, and which lives just below ordinary low-water, has its fragments carried out fifty miles from the nearest coast ; with it, and abundantly, is Patella vulgata. The general character of the sea-bed of the Channel is, that its component materials become finer as the distance from the coast-line and the depth of water increase. This relation of sea-bed to depth was long since noticed. In Lord Anson’s ‘ Voyage’ (1740-47) he states that he has tried soundings more frequently, and in greater depths, and with more attention than had been done before, and from the remarks occasionally made on their value, and the occasions on which they were taken, he seems to have relied on them when navi- gating unknown seas, as a sure indication of his distance from some land. His observations give 80—60 fathoms fine sands, mud and ooze, 60—40_ ,, sands with broken shells, 40—12 ,, coarse sands, pebbles and small stones, and appear generally to have been taken along lines of open coast. These numbers are not here produced as the rule or scale of depths regulating the distribution of materials by the sea. But if we take lines of soundings seaward, we shall invariably find a progressive change as we advance from deep water and open sea, from mud to mud with sand, next sands which increase in coarseness ; small subangular pebbles ; and across beds of water-worn materials, described as of the sizes of peas, coffee-berries, beans, almonds, pigeons’ eggs, &e., till we finally reach the marginal banks of gravel and shingle ; so that the term soundings is well made to designate both the depth of water and the nature of the sea-bed—the condition of the one being the result of the action of the other. The bearing of this relation of sea- bed to depth, to what forms the greater part of the detail of pure geology, is obvious: the vast series of sedimentary deposits, nearly the whole of our areas of dry land, are the aggregates of the soundings of ancient seas, presented to us in their progress through long periods of time*. Among the more interesting points connected with the subject of the older sedimentary deposits, are those known in descriptive geology as—§ 1. Mineral character; § 2. Stratification; and § 3. Sequence of deposits. § 1. Mineral character is simply the result of the process of distri- bution by a body of water in constant motion—an operation, the pre- cise counterpart of what is employed in various economical processes whereby mixed materials are separated, arranged and carried forward according to size and specific gravity. The divisions on the Map of * T had long since entertained the notion that geological speculations might be greatly assisted by a careful study of any given area of sea-bed (Geol. Trans. vi. p-. 454), and the notes from which this paper has been drawn up date back many years ; but I am ashamed to confess that at the time it was communicated to the Society I had not read Mr. Darwin’s Observations on South America: the whole work is a rich store of facts and correct inferences, and as bearing on the ob- servations contained in this part of my paper, I would refer to Mr. Darwin’s first three chapters, and more especially to the first— December 1849. 78 PROCEEDINGS OF THE GEOLOGICAL society. [June 13, the bed of the Channel are as distinct as any which we establish on geological maps between portions of formations which differ mineralo- gically,—as between the lias clays and the oolitie sands which sur- mount them. The mud beds forming in ninety fathom water in the central trough of the Channel, are geological marls and clays; the only difference they present from one place to another being dependent on the source whence the constituent particles have been derived. On the English and Irish side of this deep area, the sea-bed is a black impalpable mud, the shells of Dentalium apparently very abundant, an accumulation such as in former seas has produced beds of lias, gault, or London clay. On the French side of the basin are white and yellow marly beds of like tenacity, and at the same depths, being apparently the finer particles derived from the feldspathic rocks, which the rough seas of that angle of the Channel are unceasingly abrading. Under the deeper water of this central area we obtain soundings of a mixed mud and finest sand, the exact counterparts of beds we are familiar with in connexion with the argillaceous portions of every formation, and which here seem to serve as a connecting group between areas of totally distinct mineralogical characters. An area which would contrast strongly with that of mud and ooze, could the bed of the Channel be raised into dry land, would be that of the clean siliceous sands, which would present a continuous extent of surface equal to two-thirds of the South of England. The forma- tions with which such areas as these suggest comparisons, are that of Bagshot, or the lower greensands, considered in horizontal, not vertical extent. Higher up the Channel are accumulations of sand with coarse sub- angular and rounded shingle, and largely mixed with this mass are the dead shells of the larger mollusca. There exist then, even in our own Channel, large areas over which materials of distinct mineralogical character are being separately accumulated ; and im this respect there must have been a complete identity in the operations of former times. Upon this point a difficulty has been felt by many geologists, who being well-aware of the additions constantly bemg made to the ma- terials of the sea-bed, have thought it strange that soundings should present such remarkable constancy as to depth. M. Brongniart and others have gone so far, on this ground alone, as to draw a line be- tween the cperations of present as compared with former seas, and to deny to the present seas the power of producing deposits which can in any way be compared with those of geological periods. ‘‘ Where- ever,” he says, ‘‘ we have been able to ascertain the nature of the sea- bed of any of the actual seas at distant times, we find it to have been the same as it is now.’’? Such is no doubt the case, though the illus- trations cited by M. Brongniart are not altogether unexceptionable. It may safely be admitted that in our own seas there is no variation in the depth or quality of the sea-bed. The soundings now obtained agree with those laid down by Captam White; and the French sur- veyors of their western coasts confirm the same fact, in the direct observations taken for the verification of their charts. The places are very few where fishermen and pilots seem to think that any vertical 1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 79 accumulation or depression is taking place—any at least of a perma- nent character ; and the reason of it is, that accumulation does not take place in this direction, but according to a process of outward distribution already alluded to. The materials of the sea-bed are in equilibrium with the moving power of the water at every place; the sediment of the ninety fathoms’ depths could not remain between the mainland and Alderney for a single tide. Should any extraordinary action of the sea, such as that of a continued gale and high tides, produce along the submarginal zone a deeper disturbance than usual, the common effect is, that an accumulation of sea-bed is brought up from such deeper zone and thrown down on a shallower one: such a disturbance is not unusual, but the effect is not permanent ; such ma- terials being within the ordinary moving power of the sea in their new place, are soon carried away*. In the course of last summer I received some curious information respecting the formation of such temporary banks, from men engaged in the oyster fisheries on the French coasts. It seems that with a continued gale from the west, large areas of their dredging-grounds become at times completely covered up by beds of fine marly sand, such as occurs in the offing, and which becomes so compact and hard, that the dredge and sounding-lead make no im- pression on it: with the return of the sea to its usual condition, a few tides suffice to remove these accumulations. § 2. The large areas of uniform sea-bed, wherever there are long Imes of uniform depth, are the obvious results of the laws which we have seen determine the quality and distribution of submarine ma- terials. The termination of deposits of a well-defined character, such as the shell-gravel beds or those of clean sand, is often by slopes more or less steep; the two conditions taken together point clearly to the mode of accumulation. If we take the great sand plain, the particles brought down are drifted on over the horizontal surface, till they reach the edge of that quality of sea-bed or soundings; they then fall over the slope, and are beyond the reach of the combined action which has moved them along: it is only therefore in advance of each area of definite character that the materials belonging to it are ulti- mately deposited. It is this process which has produced that dia- gonal arrangement to be observed im so many deposits from the crag to old red sandstone. The red crag shows us instances of the coarse- ground sea-zone, the coralline crag of the region of shell-sand. A modification of this arrangement is presented by these two groups; in the red crag we meet with a structure which may be called torren- tial, by an application of M. Necker’s term; with this we meet with constant instances of the partial removal of the upper portions of subordinate beds, subsequent to their accumulation: with the coral- * The Schole bank rises out of twenty to twenty-five fathoms water. In 1824, _ Captain M. White describes it as having steep sides and covered with only seven and a half feet of water. He surveyed it again in 1831, and found it much in- creased in size, with regular soundings about it. In 1833 the French surveyors found it much in the condition in which Captain White first described it. Such an instance as this indicates only rapid accumulation for a few years, followed by as rapid removal. There are many cases of like character, but they all belong to the submarginal zone at most, and to this very rocky part of the Channel sea-bed. 80 PROCEEDINGS OF THE GEOLOGICAL Society. [June 13, Ime crag there are seldom continuous beds of great extent, but a simple arrangement of diagonal laminze. Portions of the lower green- sand present us with instances where the component strata are carried on for great distances, with their upper and lower planes strictly parallel, and with cross structure throughout in the same direction : in these cases the angle of lamine is uniformly higher than m the more confused and shorter bedding. The angle of rest for drifted sand will be high in proportion to the stillness of the water mto which the sand-bed is extending itself; so that in these several well- known characters of deposits we seem to have a guide as to the con- dition of depth and directions of moving power over these old sea-beds. In the torrential structure of river deposits the direction of the bedding is with the stream. In marine beds we constantly meet with it, as in the pleistocene drift and crag deposits, setting in opposite directions in consecutive beds, as contradistinguished from those setting constantly in a given direction. In the first case the mate- rials are mostly mixed and coarse—laminated sands, between hori- zontal gravel beds; im the latter the materials are finer, and indicate the undisturbed process of constant outward accumulation. In the confused stratification alluded to, and im the thin layer of sand which is so constantly interposed between masses with opposite diagonal bedding, we have an arrangement which may be due to tidal influence. If we take a portion of the east end of the Channel, and where the tidal movement of the water is well known, we find that the flood at the syzygies runs 45 40’, at the ebb 6% 50'; that the mmimum velocity, which depends on the height of the tide, is at most half of the maximum velocity, or that with high tides the flood is more rapid — than the ebb. Making allowance for these different forces and direc- tions, the confused arrangement to be observed in these deposits be- comes intelligible. In the deeper sea sand beds, which travel outwards by additions in front, the formation of a single stratum may be contmued until the effect of its accumulation is such on the body of water entermg such sea as to admit of a new bed being formed above it; so that the interval of time between one stratum and another in this zone may be very great. The dimensions of strata of this kmd are greater than those presenting other arrangements. Diagonal beds of great thick- ness may be noticed in the crag deposits, and I have seen them up- wards of twenty feet thick m the lower greensand, a thickness which would correspond with a sudden increase in soundings of from three to four fathoms. A very common form of arrangement is where the lines of deposi- tion are parallel with those of bedding ; im this case we seem to have no guide as to zone of depth. We meet with it in the so-called raised beaches, which are marginal sea-beds, ranging down to 10—15 fathoms. The stratification of the beds at Braunton is most distinct and re- gular. This mass is the shallow water accumulation of a sheltered bay ; but we may trace the same arrangement in beds which were evidently deep and wide sea deposits, such as those of the white chalk, orwhere like masses have been altered into crystalline limestones. 1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 68] But even here, in proportion as one part of the formation affords in- dications of greater depth than the rest, as between the chalk marl and upper chalk, so stratification becomes less distinctly marked : the deep sea mud-beds, such as the old slate rocks in their original condition, the London and other great clay groups, are not stratified, but only laminated. Lines of stratification are obviously due to an interference from time to time in the process of horizontal deposition, but as to the cause in this particular case I am unable to offer any conjecture, nor can I meet with one. In a sea where accumulation goes on by an outward distribution of materials, there will be an obvious tendency to form banks and terraces. The termination of the sands over the mud-bottoms are of this character, and such are also the accumulations of a higher zone which surround the deep pits between the coasts of France and those of the south-west of England. In order to realize the geological bearings of such processes as we have here considered, we have only to imagine a long valley formed by subsidence or otherwise, to be so placed that the waters of an ad- jacent sea should flow in and occupy it to the depth of 100 fathoms. The nature of its action would be as follows: The products of wave destruction along the coast-line would be carried outwards and ar- ranged in zones according to states of comminution and specific gra- vities; simultaneous accumulation of all these various conditions of detritus would take place, and if followed from the coast-line outwards would present a gradual change from one mineral character to another. By lapse of time and process of accumulation, the bed of such an area would be raised, the depth of water diminished ; sands would then be carried out where silt and ooze had been deposited at first, and beds of coarse materials would occupy the zones of finer sands. The accumulations from either side might thus be brought up, till a large portion of the area would have the kind of sea-bed known as coarse- ground. When the higher portions of such channel no longer offered any places for the finer sediment, it would travel outwards, or towards the opening and lower portion of such depression ; and the whole of such an area would bear the same relation to the wider ocean with which it communicated, that its own river estuaries bore to itself. Such is the actual relation of the English Channel to the Atlantic Ocean: itis the estuary of the rivers of a portion of Western Kurope, in which are repeated on a wider scale all the phenomena of tidal action which minor estuaries exhibit. In the case here imagined, we have assumed a given area or valley of depression, modified afterwards by the process of accumulation alone ; the whole of the process would be conducted along a very narrow zone of breadth compared with the extent of the sea, whenever the sea was an open one, and for all geological purposes such lines of section will perhaps be safer guides than those taken in close seas. In our own Channel, as we shall see, the area of sedimentary deposits is bounded on the west by the barrier which separates it from the great valley of the Atlantic: the distance of the deep sea mud from Cape Clear south is about the same as that of the same deposit from the Scilly Isles, VOL. VI.—PART I. G 82 PROCEEDINGS OF THE GEOLOGICAL society. [June 13, and agrees with the distances given below, the results of a number of lines of soundings derived from charts. The inference we must derive from this is, that extended lines of deposits, having an uniform mi- neral character, must have had at their periods of deposition a certain parallelism with the coast-lines of their seas. § 3. The necessary and obvious result of a process of accumulation where the quality of the sea-bed is dependent on depth and distance, and where the progress of the several zones of materials is outwards, will be, that in process of time each distinct zone of mineral matter will overlap the one immediately in advance of it. A deep sea channel thus filled up would present, in the long vertical sections through its bed (which is the manner in which we look at ancient sea-beds), a gradual change in mineral character ; the tenacious mud would pass into fine silt and ooze—the original deep water beds; after a cer- tain amount of accumulation, these would be surmounted by the sands of the next zone of depth, a progressive increase in the coarseness of this arenaceous series would be observable; lastly, the coarse ground zone would be found running out and resting on that of clean sand: throughout the series, taken as a whole, there would be a regular order of superposition. If we imagine a sea-bed, a 6, thus accumulated, to be subsequently raised to an uniform level, without any reference to the former depths of deposition, just as the deposits of the se- condary and tertiary periods mostly are at present, and be made to exhibit a section at right angles to its coast-line, we should have, first, such a succession as represented fig. 2; and which if described in Fig. 2. Argillaceous beds. Sand and sandstone strata. Gravel beds. ——————$—————$———— ZL LY, iiddiamaaei TLD LLL LLL Middle zone of clean and shell sand, small pebbles. Shingle banks. a. Deep sea mud. the ordinary language of geology would be—a thick ascending series, commencing with clays and marls, or pure limestones, according to the preponderance of the remains of animal life (Zoophytes, Mollusks) over that of the mimeral masses on the coast-line, passing up into and succeeded by a vast accumulation of sand, and finally surmounted by coarse beds of gravel and shingle: concurrently with this mineral change, there would be another as great im the suites of animal re- mains, if we confined ourselves to such as should indicate that they had lived at the places where they might occur. With respect to the finer and more distant sedimentary beds, the change upwards in mineral character would be progressive; whilst in other cases, and nearer the coast-line; where an accumulation of sand or gravel might have travelied out with a diagonal arrangement over a previously formed sea-bed, the line of separation might be very de- fined, or as we should say geologically,the mineral character would change suddenly. All these appearangés might be presented, and yet not warrant the supposition of any violent physical change; the sea- bed of this and of every past period must be considered as a syn- 1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 83 chronous series, of which every portion has been derived from one -common source—the coast-lme. At particular places, im sections taken through them, masses of one set of materials would be found resting on another, as sands upon marls, and gravels upon sands; and we might find these sands dipping away as a mass from the one, and passing at the distance of a few miles beneath the other, as in section fig. 2; yet the only inference will be that the marl beds, which, im a vertical line, are beneath a mass of sand, are before them in re- spect of time; not, as we now imagine, that any one group or portion of a series had priority as a whole. The application of these several conditions of accumulation to the deposits which form our tertiary and secondary series of formation, forms the second part of this communication: and the only point I would now notice, connected with the bed of the Channel, is the re- markable irregularity it presents at its western boundary, but which it would have been premature to have noticed in the early observa- tions on the Channel as a physical area. The law of progressive change in the character of sea-bed requires that the most remote deposits of the Channel should be the finest, and that no coarse materials should occur at any considerable distance from the coast : this law holds good for a given extent round all the shores of the Channel, but beyond the area of mud and ooze, fine end coarse sands, shingle and bare rock are again met with. It will be seen by the map that the Channel bed slopes gradually west through 8° or 9° of longitude, but that instead of running on with such inclination into the valley of the Atlantic, after having attained a depth of 90 and 100 fathoms, it rises again to within 50 and 60 fathoms of the sur- face: it is on the sides of this rise that the coarse beds occur. The moving power of the sea at 60 fathoms (the highest level of these rises) is limited to fine sand; but the whole of these groups, whether the Sole Banks or Jones's, are separated from the zones of coarse ma- terials depending on the coast-line, by a broad intervening area of the finest quality of sea-bed. We are precluded from supposing that the lines of coarse materials can have travelled over the mud zones, as their upper surface is soft and incoherent, into which the sounding- lead sinks some distance before the mass is tenacious enough to stop it, and in which the dredge buries: if therefore marginal or sub- marginal zone materials are found in places beyond well-defined areas of the low moving power of water, they become a clear indication that since their accumulation a great change in the position of such place, as to depth of water and distance from coast-line, has taken place. If we take the contour-lines of the Channel valley as they are given on the accompanying map, beginning from the coast, it is very evi- dent that they conform to the features of that coast-lme, particularly where it is due to physical structure ; a larger scale, and an interme- diate 5-fathom line would show this in a very remarkable manner, in the case of one or two valleys of fracture: the features derived from the direction of given masses are continued through the submerged portion of the valley, and are merely modified by the quantity of modern sea- bed accumulated over them. Thus the Channel Islands are the west G2 84 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 13, extensions of the masses of crystalline rocks of the Cotentin, which occur in the cliffs of its coast at places due east ; the submarine run of these masses is indicated by the rocks across the intervening sea : it is the unyielding granite ridge, which connects the granite of Al- derney with that of Cape la Hague, that causes the race at that place, and so throughout the whole of that group (wide Map). On our side of the Channel the mineral character of the crystalline rocks is dif- ferent from that of the Cotentim and Brittany; the granite of Scilly belongs to the west of England group, and due west again is Jones’s Bank, a nucleus of solid rock vested with granite sand and shingle. This conformity of contour-lines to the coast becomes weaker as we proceed seawards, and at the distance of the 50—70-fathom lme of soundings has only a general agreement with it; the deep sea-beds are spread out over this area: beyond these the configuration of the sea-bed begins to put on a new direction, and in its extension west we find that this depends on the form of the mass, which rises between 48° and 49° north lat. and 8°30° to 10° west long. The places along the opening into the Channel at which we meet with shingle and gravel are very numerous; some of these are indi- cated on the map, but the scale is too small for the admission of all ; but with respect to them all, we must suppose, as in the case of the Little Sole Bank, that they are the indications of a marginal zone or coast-line. It may be objected to this, that these distant sand, gravel and shingle beds may belong to any age, and not in any way be connected with the present seas. In tracing the remains of marine animals sea- wards, we may observe a like gradual comminution with that noticed with respect to mineral materials, long after the forms of shells have ceased to be recognizable. The sea-bed, particularly on the French side of the Channel, is mainly composed of shell-sand, or sand in which few particles of anythmg but such as show shell-structure occur. Areas of this character are laid down by the French sur- ~ veyors, and occur in the interval between the Land’s End of France, or Ushant, and the Little Sole Bank; yet on the sides of this bank, and more particularly on its western slopes, large, perfect, though decayed shells again occur, and what is more remarkable, Patella vulgata, Turbo littoreus, &e. Taking the two phenomena together, the oc- currence of littoral shells and of marginal shingle, we may safely infer that we have at this place the indication of a coast-line of no very distant geological period, buried under a great depth of water, and removed to a great distance from the nearest present coast-line. The duration of time, estimated in the ordinary measure, during which the sea must have worked at its present level, must have been very great, from the extent and uniformity which its zones of deposit have attained with relation to that level; and it may be argued, that if such be the case, these coarser beds and littoral shells would not now lie exposed on the sea-bed, but would long since have been covered up by the accumulations of fine deep-sea sedimentary matter. The obstruction the Little Sole Bank offers to the flow of the tidal stream into the Channel—the surface-disturbance resulting from 1%, 1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 89 which is always to be observed over the whole of the area—the sus- pended matter which the water here indicates—alike favour the suppo- sition that the minute particles of matter which could alone find their way to such a distance, could not accumulate at such a place. If on such evidence we assume that the whole of the Channel valley had at some former period a higher level than at present, many other anomalies become intelligible. The banks of the Channel, such as Jones’s, have tabular summits, often of rock, whilst the sides are steep, and composed of coarse materials ; they are just such masses as some of the groups of rocks (such as have been already noticed in the vicinity of the Channel Islands, and which have been cut down b the prolonged action of the sea at a given level) would be if let down into fifty fathom water. The summits of all the Channel banks keep nearly the same depth, and would seem to point to some former higher and common level, for their distance from the present surface is such that the sea cannot possibly affect them mechanically. In the very coarse beds which form the floor or lowest levels of the Deeps in the upper part of the Channel, from the meridian of Cape la Hague eastward, and which have a depth of forty and fifty fathoms, we also seem to have the highest marginal zone of some former period, over which the drifting beds of the actual period are spreading ; and on the other hand, such masses as Jones’s bank are to be considered as protruding portions of an older sea-bed isolated amidst the ooze de- posits of the present sea. The data are as yet too few to enable us to determine whether indi- cations of more than one former permanent level can be detected in the characters of these portions of the Channel bed ; but there is enough to warrant the conclusion, that at certain places former depths must have been different, and apparently less than they are at present, and that one such marginal level existed about the line of fifty to sixty fathoms. There is yet a point to be noticed connected with the physical history of the Channel valley, and that is the nature of the rise which takes place at its western extremity, and which serves as its boundary with respect to the Atlantic depression. The Little Sole Bank has depths on its eastern side of ninety fathoms; but this rise is very trifling compared with that which its western slopes present. I have attempted a representation of the outline of this portion of the Chan- nel sea-bed, by the aid of the soundings which have been taken by the French and English surveyors ; and in explanation of it, it may perhaps serve to give a better notion of the extent of mequality of surface here indicated, if I borrow an illustration from the physical features of a well-known district, than to attempt to represent it by sections*. Within a distance from the summits of the Little Sole Bank, not so great as from the top of Snowdon to the sea, soundings have been obtained of 529 fathoms; in other words, the Sole Bank rises from that level to a greater height, and more rapidly, than does * Lengthened sections having au approach to a true scale accompanied the paper when read; these cannot be reduced, and to alter the scale of distances and depths would be to do away with their use. 86 PROCEEDINGS OF THE GEOLOGICAL society. * {June 13, the mass of Snowdon from the sea-level of the Caernarvon coast by the Menai Straits. The character of the greater part of the Channel area, if laid bare, © would be that of extensive plains of sand, surrounded by great zones of gravel and shingle, and presenting much such an admixture and arrangement of materials as we may observe at present over the Bag- shot district of deposits; whilst along the opening of the Channel there is an obvious configuration of hill and valley, and an amount of inequality equal to that of the most mountainous part of Wales. From the summit-levels of the Little Sole Bank to the 200-fathom line of soundings on the west, the slopes, though steep in places, are regular. If we deduct the fifty fathoms of water, the remainder will give 900 feet for the elevation of this ridge above the 200-fathom level; or a range of hills having just the same uniform tabular eleva- tion above such line that the Haldon and Blackdown ranges have above the present sea; it is about the lower levels of this group that the coarse materials already noticed seem to occur. Beyond the 200-fathom line the outline is irregular, and sinks rapidly to very great depths. This remarkable fact occurs not only at one particular spot, but is continued northwards, and in the con- trary direction has been traced by Captain Vanhello from Cape Finis- terre to the parallel of the Lizard. The investigation of this line seems to have been the special service on which he was employed in 1828 and 1829. He states that immediately beyond the 200-fathom line they often failed to obtain soundings by running out as much as 400 fathoms ; and also that the ridge of the Little Sole is placed on the east edge of that 200-fathom lme. Of the true nature of such a sudden line of depression we can at present only form conjectures : it may represent lines of old escarpments; or should lines of sea-cliff have gone down rapidly into deep water, where no mechanical action could modify them, such features would be preserved : lines of faults and upheaval would also present such unequal soundings; but the outline is too irregular to represent the termimation of the sedimen- tary mass of the present seas; besides which, we have constant indi- cations of a surface of bare rock. Sir H. De la Beche has represented the course of the 100-fathom line round the British islands*, with which that of 200 fathoms has a very close conformity, and he remarks on the agreement which this line presents with that of the strike of the older ranges of this country : such is undoubtedly the case with respect to a portion of this line; but if it be suggested by this, that the date of this sub- merged line be the same as that of M. E. de Beaumont’s ‘System of the North of England,’ it must be remembered that this 200-fathom line, if viewed along its entire length, presents no such parallelism,— that it is contmued along the coasts of countries whose ranges present * Theoretical Researches, p. 190. In closing these observations on the con- dition of the bed of the Channel, I gladly acknowledge my obligations to this work ; to it, and Sir C. Lyell’s ‘ Principles,’ I must trace the idea I have attempted to work out. 1849.]| AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 87 no accordance with that of the north of England,—and that it crosses at right angles, and cuts off ranges, which not only have been raised, but were deposited long after the ‘System of the North of England’ rise took place. § 2. dge of the Channel Valley. The valley of the Channel being due to depression and not to ex- cavation, the geological period of such depression is another obvious point of interest connected with it. From the parallelism of the valley of the Channel with certain lines of elevation along the South of England, Sir Charles Lyell has sug- gested that the movement from which this configuration resulted might be referred to some portion of the eocene period: but with such an abrupt termination as the Bagshot series presents, and with the occurrence of the lower portions of the eocene deposits up to the very edge of the chalk escarpment of the Wealden denudation, we must suppose, as we do with respect to the secondary beds of the same district, that the whole of the eocene group, as it exists in the South- east of England, was originally carried continuously over the Wealden ; and that the phenomena of denudation of this district are entirely re- ferable to some post-eocene date: geological features, or rather phy- sical ones, may present parallelism, but these will be found to have very little connexion with the question of geological age. The only way by which to test the relative levels which portions of a country may have had at any distant time, is by the beds which occur over them. If of two areas, one presents a surface of eocene strata, and the other, like eocene deposits, surmounted by distinct and younger beds, of the existence of which the other area offers no indications whatever, we rightly infer that these two areas had in the interval assumed different relative levels. Such is the difference be- tween the two valleys of the English and German Channel—the crag deposits occupy both the English and Belgian sides of the German, whilst they are altogether wanting in the English Channel valley. Between the uppermost freshwater deposits of Hampshire and the Isle of Wight, we have no indication whatever of marine beds con- taining intermediate forms between those of the eocene and present seas. Marine beds containing existing species occur at intervals along the coast-line of the English Channel : they were never probably con- tinuous, and all belong to the marginal zone. The movement of the materials of this zone, in the present state of the Channel, has been noticed in the former part of this paper, as taking place in a direction from west to east. In a description I gave of raised beaches at the entrance into Tor- bay and at Slapton, I stated that chalk-flints, and other materials from rocks to the eastward, entered into their composition, and that these materials were not to be found in any of the beaches in the vicinity at present. I re-examined these beds in the course of last summer, and found the proportion of chalk-flint, in subangular frag- ments, far greater than from recollection I had supposed it to be. It must not be understood from this that chalk-flint pebbles are not to 88 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 13, be found with the shingle on any West of England beach at the pre- sent day ; a great mass of fimt shingle occupies the middle portion of the Channel far beyond the range of the chalk strata on the coast: and these very raised beds must have continually supplied a portion: the difference consists in the amount of wear, and rela- tive proportion—on the present beaches they are exceedingly scarce, and only in the condition of rounded shingle: the like holds good with respect to the raised marine beds with chalk-flints at every other lace. Sir H. De la Beche has noticed the presence of chalk-flints in the “raised beaches”? he has described on the coast of Cornwall, and adds, ‘“‘ The occurrence of these flints, as at Coverach Cove and at other places in the Lizard district, while they are not found mland in the adjoiming country, is not easy of explanation*.’”” On the other side of the Channel a like mixture of chalk-flmts with other materials -is described by Sir W. Trevelyan in the raised marme beds about the Channel Islands+. Such facts clearly indicate that the marginal movement of the materials, during the period of accumulation of these raised deposits, was from east to west along either side of the Channel, or the reverse of what takes place at present. These accumulations have hitherto been noticed as proofs of re- cent changes; but in my communication on the subject in 1834, I noticed the poverty of the marie fauna of the period to which they belonged, and suggested that the sea-waters were then less favourable to marine life than at present, owing to a lower temperature. If the observations of the several geologists who have described the pleisto- cene period and its beds { be kept m mind, when considermg the raised beds of the West of England and coast of France, it will lead I think to the inference that they also belong to the pleistocene epoch. The raised marine beds of the coasts of Cardigan and Merioneth can- not be separated from the pleistocene beds of Wicklow and the op- posite coast. The intervention of the area of the Bristol Channel is not sufficient to cause similar deposits on the north coasts of Somerset, Devon, and Cornwall, to be considered of a different age from those on the Welsh coast. From the Irish Channel to the western coasts of England, and to those of France and the Channel Islands, we have a continuous series of like phenomena; and if one portion is of pleistocene age, so is the whole. The bearing which this view of the age of these deposits has on the physical history of the English Channel is not without imterest. A portion of the pleistocene littoral zone of sea-bed is preserved on the coast of Sussex, where it was first noticed and most accurately described by Dr. Mantell: these beds serve to connect the history of the east and west extremities of the Channel. The Brighton beds contain (as is well known from Dr. Mantell’s description, as also to all those who may have examined them) that admixture of foreign crystallie rocks which is so characteristic of the pleistocene accumulations of the * Report on Devon and Cornwall, pp. 429-646. + Proceedings of the Geological Society, vol. vii. p. 577. ¢ More particularly Mr. Morris on the valley of the Thames. 1849.| AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 89 Eastern counties. These rocks belong to the Northern ocean area, and must have passed from that into the area of the English Channel. We thus arrive at the precise date at which the English Channel be- came sufficiently depressed so as to be occupied by sea, as well as at the date of the subsidence of the chalk strata along the north and south line before indicated, and which produced the Dover Straits. The movement of the drift materials over the Northern and German ocean area during the pleistocene period was from north to south ; and when the Channel valley was opened to the waters of that period, the drift was continued with a like direction into that area: im like manner the chalk-flints of the eastern portions were made to travel west ; and in the meagre character of the marie fauna of the raised beds of the Channel, we see that it was influenced by arctic currents, and not southern ones as at present. The levels of the portions of the littoral zone of the pleistocene period in the English Channel show the depression of that area to have been rather lower at that time than it is at present. There would also appear to have been an intermediate level, of which the shingle bed between Brighton and Rottingdean is a familiar illustration—a level which was of sufficient duration to allow of the formation of cliffs ; the Elephant bed, as it is named by Dr. Mantell, belonging to a vast series of deposits, to be noticed in the sequel, and of the age of the drift. = —— = TLL LLL ELLE LEZ Ss 5 2 ee FT y, YY A YY Yyfllllldda Vita : SS Ss The drift beds are the uppermost portion of the pleistocene group ; and under the name of diluvium were long since traced down into the Thames valley, and fully described as to their characteristic admix- ture of northern materials by Dr. Buckland. On the south side of the Thames they may be seen extending over the surface of the ter- tiary district, in many instances overlapping it, and resting on older denuded strata. But as we approach the district where the physical features of the Wealden begin to show themselves, these accumula- tions diminish in thickness, till at length we reach an area over which no trace whatever of them is to be found. This termination of the pleistocene drift takes place by a well-defined marginal bed, of which clean sections have recently been exhibited im the cuttings of the Reading and Reigate Railway. The detail of about twenty miles of this coast-line, where it ranges across the countyof Surrey, will be sufficient, as all that I wish is to connect the phenomena north of the Weald with those on the south. If we commence with this line at Farnham, 90 PROCEEDINGS OF THE GEOLOGICAL Society. [June 13, we find that the chalk range subsides for an interval, and gives way to a low tract covered superficially with gravel. This accumulation 1s spread out westward along the valley of the Wey, and abuts against the ridge of lower greensand which bounds the stream, and which evidently defined its limits. In other places the gravels thin out against the slopes of the higher ground, as underneath Crooksbury, where their sides are occupied by it : good instances and sections may be seen, first, in the cuttmg near the Mill, and on the road to Moor Park, as also in the Pine-wood beyond Waverley : the teeth and the tusks of elephants have been lately met with in these gravels, in extra- ordinary abundance. The character of the accumulation about Farn- ham is better conveyed by a woodcut illustration than by verbal de- scription (fig. 3). : From Farnham the gravel beds pass outside the chalk range, and not the slightest trace of them is to be found m the valley between the escarpment of the chalk and the lme of hills south of it. At Guild- ford the gravel passes through the break im the chalk, and is thence spread out over the area of the Peasemarsh (fig. 4), and ends off with an uniform level agaist the base of the hills which encircle this valley. The remains of elephants, as well as of other animals, are very abundant at this place. The railway-cutting from Guildford to Godalming (fig. 5), and from Shalford to Postford (fig. 6), has given . (oP eee I ers An SNS ZZ LZ, LIZZ sections of these gravel beds; which in heir marginal character, by the mixture of gravel and shingle with sands diagonally arranged. The boundary-line is here also well-defined. The condition of this part of England antecedent to the accumula- tion of the pleistocene beds is well shown in the Peasemarsh: the remains of trees are found beneath the gravels with elephants’ teeth and tusks; in one instance so many bones occurred. together, in the clay which underlies the gravel, as to warrant the conclusion that an entire skeleton was buried at that spot. A north and south section from this marginal line of drift, as from Guildford or Farnham to between Brighton and Rottingdean, would show the pleistocene gravels, with characteristic animal remains, end- ae 1849.| AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 91] ing off at nearly the same level against a central area, over which no trace whatever of such gravels is to be found, and thus msulating it in the pleistocene sea. At Dorking the geological phenomena of the Guildford valley are repeated. A series of raised marine beds, as already described, surround the West of England on the south-west and west ; and except at inconsi- derable heights, we find no traces whatever of any drift beds over this area. Here again the highest drift beds with elephants’ remains are above the pleistocene beds with shells, as they are on the Sussex coast : such was the position of the Plymouth beds described by Dr. Moore*. The whole of the South of England, from the Wealden area on the east, to the Land’s End, does not appear to have been a continuous Ime of dry land during the pleistocene period. Between the two tracts here noticed we find a wide interval over which water-worn materials of distant origin occur abundantly. The whole of the valley of the Exe is filled with an accumulation of this sort, derived from the rocks of North Devon; these beds spread out over the country east and west of the actual course of the river, and have afforded elephants’ remains from a variety of places and elevations. Dr. Buck- land was the first to call attention to the curious fact of the occurrence of pebbles of milky quartz over the highest levels of the Blackdown range. I have described elsewhere the characters by which the bed which contains these pebbles is to be distinguished from all other ac- cumulations of the district, as also the fact of its distinct superposi- tion}; and in spite of the present elevation of the Blackdowns, I see no solution of the difficulty but by supposing that the whole of that area was submerged during the latest portion of the pleistocene eriod. , The western boundary of this interval of depression, or perhaps better the coast-lme of this western island in the latest and highest range of the pleistocene sea, is well defined along the northern extre- mity of Great Haldon, by a clean outline of water-worn materials and immense blocks, which occur from that point by Whadden Barton, Chudleigh, round the Bovey valley, particularly at Pen Wood, Staple Hill, and thence to Newton. For the evidence that all this material has travelled south—that all the remarkable faults and fissures of the Chudleigh district were produced. before the dispersion of this gravel ; as well as that the difference of level which it occupies in the Bovey valley and on the summit of the Haldons, is due to changes of level which have taken place since their accumulation, I must refer to a former notice of the districtt. The strongest proof of all, that the highest levels of the Haldons and Blackdowns (900 to 1000 feet) must have occupied a low level with respect to the Dartmoor group, is, that the summit gravel contains pebbles of its schorly granite. The two areas of the South of England which thus seem to have been insulated in the pleistocene sea, have certain physical features in common, the prominent one being the east and west axes of their mineral masses. The boundary-line of the pleistocene drift from the * Report of Brit. Assoc. 1841, p. 62. + Geological Transactions, vol. v. + Tbid. 92 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 13, coast of Belgium runs parallel with the east and west range of the Netherlands ; and such also, according to the line traced by M. Berg- haus, is its direction across the continent of Europe. South Wales presents a like east and west arrangement, and does not seem to have been submerged. In the South of Ireland again, we have a district where all the physical features are dependent on an east and west di- rection ; and here again the drift beds, which are so widely spread over the rest of Ireland to the northwards, are altogether wanting. ' The geographical aspect of the north-west part of Europe at the period of the furthest range of the pleistocene sea would, according to these views, be somewhat such as represented in the map*. The northerly areas of insulation are taken from Prof. E. Forbes, and are in perfect accordance with the pure geological evidence of the greatest amount of depression which the north of this island presents. In this view I have considered all stratified wide-spread gravels containing elephants’ remains to be of the same period with the upper- most pleistocene drift, whether the deposits contained marine shells or not. The elephant remains, so abundant even in the highest pleistocene bed, are commonly treated as those of the animals of that period. These remains occur in the neighbourhood of the Wealden island, and indeed everywhere, under two very different conditions. 1. In the beds of ancient lakes, ponds, or river-beds, where, as at Petteridge, Peasemarsh, Valley of Arun, &c., great quantities of bones and entire skeletons occur. 2. In the sands and gravels of the drift : im these beds the remains consist of the harder portions only, and are mostly water-worn. A recent examination of the Crag deposits of Suffolk, in company with Mr. Prestwich, Mr. Morris and Mr. Tyler, has satisfied me that the change from pliocene to pleistocene conditions took place by gradual subsidence, and consequent decrease of the area of dr land of England which was contiguous to the pliccene sea ; that this was attended by a diminishing temperature ; and that the marine conditions, so far as animal life was concerned, had assumed their arctic character long before the whole of Northern Europe had reached its greatest amount of depression. The remains of the land animals have, in the case of the drift beds, been derived from the sweeping of the surface of the area of dry land over which the plei- stocene waters spread, and over which surface such remains might have been accumulating for countless ages. These, and the remams in the bone-caves, represent the fauna of the whole period during which the principal part of this island was in the condition of dry land. The period at which we have clear evidence of the area of the Channel having been occupied by sea, is separated from the eocene formations by such a long lapse of geological time, that a glance at its condition durmg the interval forms a necessary part of its physical history. I endeavoured to show, im a former paper on part of South Devon, that along every valley through which a river * Exhibited when the paper was read, but not included in the illustrations. + Geological Transactions, vol. v. ib 1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 93 takes its course, alluvia are to be found at elevations such as the ex- isting streams never attain. At that time I was disposed to refer these former broad river-courses to the period of the so-called raised. beaches. I have recently had an opportunity of re-examining some of these valleys, and of looking at like phenomena in other places, and I now feel satisfied that the two classes of accumulation are per- fectly distinct as to time. The volume of the rivers of a district depends directly on the amount of moisture precipitated over it, and this depends on its ele- vation above the sea; so that to depress any given area will not tend to increase its rivers. There are other objections apart from this general one; if we take any river-course opening out into the English Channel, such as that of the Dart, and suppose a depression of the land to take place of 100 feet, we should obtain a great extension of the estuary portion of such river, which portion would be permanently characterized by its cliffs and accumulations. This new water-level, though it might account for estuary beds and shells at a higher level than before, would have no influence on the upper portions of the streams flowing down into such estuary, so as to augment their vo- lume. Inthe valley of the Dart, however (as well as in all the others), there is no indication whatever of any estuary beds at higher levels than the present ones; but the ancient alluvia, which conform to the dimensions of the valley, and are distinguishable from the recent by their coarse torrential character, as well as breadth, can be traced by Holne Bridge and Staverton, till they pass down beneath the accumu- lations of the present estuary. These observations apply to every river of the West of England ; none of them show estuary beds above the present water-level, but their upper portions show alluvia which are. The conditions which alone will account for these appearances are obvious—the country, instead of having been placed at a lower level at the period of these broad alluvia, had a much greater elevation above the sea, and when the sea did not reach such portions of these valleys as it does now. This condition is not local, but is applicable to every considerable river-course in the island, along every one of which we can find indications of the larger dimensions of the former rivers. ‘The Thames and the Severn are striking examples. That the whole area of the English Channel had at one time a higher level, is directly proved by the numerous instances along its shores where old forest ground passes beneath the present sea-bed : these are marked on the map. Jt seems to be constantly assumed that the original position of these wooded tracts was close to the coast- line, or at the sea-level; but for such a supposition there seem to be no grounds whatever. Proximity to the sea is generally unfavourable to the growth of timber. . If we take the whole line of the coasts of the Channel on either side, we shall not find any wooded tracts coming down to it, or even single trees of any magnitude; yet in many in- stances the trees of these submerged lands had attained a very great size. Again, the trees which have been identified from these sub- merged woods, such as the elm, oak, chestnut, hazel, are none of them such as have their usual habitats along the sea-board. But per- 94 PROCEEDINGS OF THE GEOLOGICAL society. [June 13, haps the strongest argument is from the presence of the Pinus syl- vestris: its natural zone of growth, requisite condition of soil, great susceptibility of the fluence of sea-air, alike point to the improba- bility of its having grown in masses, or attained any size, in the vicinity of the sea. The conclusion we may safely arrive at is, that the area of the present English Channel was in the condition of dry land previous to its occupation by the waters of the pleistocene sea, or during the period of the pliocene (crag) accumulations of the German basin, and that, together with a large area beyond, it served to connect the British Islands with France on the south, and Ireland on the west, into a tract which had a far greater amount of elevation than any portion of it has at present. The geologist will require that many conditions resulting from such a state of things should have left their evidences. At many places along the shores of the Channel, thick accumulations of earthy ma- terials come down to the sea-level. The western coast affords the best opportunities for studying these beds. The bold coast-line from the Start Point westwards presents a yellow band rising from the line of high-water, and which might at first sight be taken for a line of raised marine beds: from the Start to the Prawle this bed expands in thick- ness, and forms a low cliff of loose uncemented materials upwards, of twenty feet thick. The whole of this accumulation is the result of the disintegration of the rocks of the district: throughout the whole thickness of the mass, but without any defined arrangement, occur fragments and angular blocks of all sizes, some containing several cubic feet. The accumulation is strictly local; along the whole of this line of section the angular fragments have evidently been detached from the chlorite slate precipices which overhang it, nor does it afford a single pebble which would indicate attrition by water. Followimg these beds to the mouth of the Erme, they are found on either side of the entrance, above the high-water level, whilst inland it is clearly seen that the area of the present estuary has been ex- cavated out of this accumulation. In every one of the Channel Islands group a like accumulation comes down to the sea-level, and from the more rapid disintegration of the crystalline rocks, its thickness is often very great. Here again we meet with repeated illustrations of the local character of the accu- mulation, that the angular blocks have merely fallen from masses of rock immediately above, without the slightest indication of horizontal movement. These accumulations are due to subaérial conditions, continued through a vast lapse of time, and dating back to periods long anterior to the present relative position of land and sea. The thickness of these beds increases westwards, and as atmospheric agency is greater as the elevation of the land on which it is exercised increases, it adds one more argument to many others in favour of the view, that at the period of greater elevation that of the west of England was most considerable. In the foregoing considerations, which the study of the area of the 1849.| AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 95 English Channel suggests, I have endeavoured to confine myself to those which belong to pure geology. I might however have borrowed great aid from a branch of inquiry first imagined by Prof. E. Forbes —that of the relation which an existing flora may bear to past geo- logical changes*. I would suggest whether it may not be sufficient to reduce the existing fauna and flora of this country to two periods of origin; one which has come in since the period of the glacial drift, the other that which forms the local character of several districts, which we have shown were insulated in the pleistocene ocean, and which flora has outlived all subsequent changes. In this way the characteristic plants of the south of England and Ireland + will be the residual portion of that of the pliocene period, which corresponds with that of the greatest amount of area and elevation. The Scandi- navian character of the floras of part of Wales, the Lake district t, and more particularly the north of Scotland, will, under this supposition, be the remains of the alpine regions of the same period. The condition of surface prior to the overlap of marine pleistocene accumulations is indicated by the remains of vegetation so constantly found beneath the drift with elephants’ remains; but traces of this vegetation are also met with (as over the Wealden) in tracts which the pleistocene waters never reached. Of the remains of this ante- cedent vegetation, the Pinus sylvestris is perhaps the most charac- teristic. Undoubted trees of this species, and of great size, occur over the surface of the Wealden denudation, buried in old peat bogs, and are remarkable for the great thickness of their bark—a character which becomes marked in proportion as the tree advances to a colder region. The period of the terrestrial conditions of greatest cold over the area of Great Britain would therefore be, when it was part of an area of much greater extent, and at a much greater elevation. With this extended area, and absence of internal seas, there would be, as com- pared both with the pleistocene and present condition, an excessive or continental climate. The character of the flora of such a geo- graphical condition would be at.the same time more southern and more northern. Much of what now constitutes upland sandy tracts devoid of vegetation, from insufficient moisture, would then have been included in the regions of pies and forests, of which the buried Scotch and spruce firs are the remains. In like manner the period of the marine conditions, with a meagre fauna, would be that of the greatest amount of depression and ex- panse of sea. From what has gone before we may infer that the process of submergence during the pleistocene period was gradual and progressive from north to south, the marine fauna being such as waters coming in such a direction would bring with them: the ter- restrial and marine periods of minimum temperature do not therefore correspond in geological time. Even at the period of greatest depression, the Pinus sylvestris might continue to live on over the northern insulated part of the * Memoirs of the Geol. Survey, vol. i. + Floras i. ii. and iii. { Flora iv. 96 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 13, island, which region, although at 2000 feet lower level than at pre- sent*, would still have presented a wide area, and ranges of some thousand feet of elevation. It is diminished area and elevation which at present unfit the West of England to produce that growth of oak and gigantic fir which before the period of the drift seems to have clothed every portion of the region of Dartmoor, and which would still more be unfitted for it when at its lower pleistocene level: on such low districts, however, and in a climate modified by a sur- rounding sea, some portion of a previous flora might have been enabled to live on. An examination of those portions of the several formations which occur within short distances of the coast-lme of the Channel valley on either side, tends strongly to establish the supposition of a re- currence of like conditions along the same area at several distinct geological epochs. The thick beds of shingle at certain places in South Devon (Ugbrook, Connator, &c.) indicate the proximity of the littoral zone of the car- boniferous deposits ; these beds occur upon a group of strata, which again indicate a series of antecedent local elevations, attended with the diffusion of trappean matter, over which zoophytes constructed the Devonian coral reefs: on the other side of the Channel the limestone masses of the Cotentin were evidently formed under like conditions, and at the same time: lower than these m the same series occurs the coarse shingle of the French and Jersey slate rocks. At the subsequent period of the new red sandstone, the lower beds constantly suggest conditions of marginal accumulation: the movement which attended the accumulation was one of gradual sub- sidence, but the sheet of porphyritic matter which contributed so much material to the new red conglomerate must have been for a con- siderable period at the water-level, as high in the series, and after an enormous amount of accumulation, large blocks of porphyry have been thrown down over beds which from their composition must have been deeper-water deposits than such as occur beneath them. The condition of the materials along the edge of the new red sandstone group in Calvados and La Manche is often that of true shingle, of great thickness, composed of the quartzose rocks of the district. The older strata of this part of France run east and west, and this ele- vation was acquired before the new red sandstone period; so that we seem to have the direction of an area of dry land east and west, and that of a line of coast shingle conforming to it. From this coast- line the new red sandstone sea stretched away north and east with an increasing depth, except where, as in South Devon and Somerset, islands presenting coast-masses of limestone or porphyry rose to the surface, from the spoil of which the coarse conglomerates were formed. The great blocks of porphyry of the middle beds of the new red series in the West of England, included in sands and marls, indica- * Nicol ‘‘On Recent Formations near Edinburgh,” Quart. Journ. Geol. Soc. vol. v. p. 23. Sank Soret ground JS imal ao LF graneee hk, Sones EN GLLST CHANNEL Ly KobetA Custom lig jd A P of the °F Dorking AREA scRRoUNDED \noT erg sh. rize of olives age shingle < of Walnuts shingle. coarse shingle sand | . coarse sand. | _ mudor fine hard marl. | #04. ouTodk. | ‘The figures indicate deph an fathom. sunk Sores ground a Ce Ce he ae ak ¢ ! ‘ 5 Soe > eam awh Tee Pes are r 1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 97 ting no great moving power, seem to require some such agent as that of floating ice to account for their position. Terrestrial conditions of great geographical extent, and of long duration, intervened between the oolitic and cretaceous periods: the Wealden strata of Sussex, Isle of Wight and Dorset indicate clearly, by the interchange of marine and freshwater conditions, that the Wealden area was at the sea level, or at the lowest portion of the area of dry land to which it was subordinate. It is not necessary to consider the direction of the dry land of the period; it is sufficient that no beds of the Wealden age underlie the Neocomian deposits from Trouville to Cape la Heve: the slight and even questionable traces of the Wealden in the Boulonnais show that it had its limit in that direction. The paleeozoic series of the Boulonnais had received, long prior to this, the features of elevation and folding which it now presents; the line of this disturbance extends eastwards: if pro- longed west it would pass along the English Channel, which, being occupied by the lower oolitic groups, whilst the Boulonnais presents only the middle and upper, prove it to have been relatively an area of depression. Coarse rounded shingle formed of local materials, such as of the siliceous bands of the carboniferous deposits, occurs abundantly at the base of the greensand beds west of the Haldon Hills. The equiva- lent beds in the Cotentin are also a shallow-water accumulation. Terrestrial conditions again obtained during the course of the eocene accumulations; but the freshwater deposits of Hampshire and the Isle of Wight, and which are entirely included in the area of the present Channel, indicate, by the alternation of marine, brackish, and freshwater conditions, a like position with respect to the area of eocene dry land, which the Wealden lake had presented before at the same place. VOL. VI.—PART I: a DONATIONS TO THE LIBRARY OF THE GEOLOGICAL SOCIETY, July \st to October 31st, 1849. I. TRANSACTIONS AND JOURNALS. Presented by the respective Societies and Editors. AGRICULTURAL Society (Royal) of England, Journal of. Vol. x. part 1. no. 23. American Academy of Arts and Sciences. Vol. 1. pp. 1-160. —— Association for the Advancement of Science, Proceedings of First Meeting of. Journal. Second Series, vol. vill. nos. 22 and 23. Philosophical Society, Proceedings of. Vol. v. no. 42. Asiatic Society (Royal), Journal of Bombay Branch. No. 12, 1849. Astronomical Society, Memoirs of, vol. xvii. Monthly Notices, vol. vii. Belgique, Académie Royale de. Mémoires, tome xxiii. Bulletins, tome xv. partie 2, and tome xvi. partie 1. Annuaire, 1849. Mémoire sur la Fertilization des Landes de la Campine et des Dunes ; par M. Eenens. Berlin Academy, Abhandlungen for 1849. Bericht, from July 1848 to June 1849. British Association, Report of the Eighteenth Meeting of the. Calcutta Public Library, Catalogue of, 1846. Chemical Society, Quarterly Journal of. Nos. 6, 7. Dublin, Journal of the Geological Society of. Vol. iv. part 1. Edinburgh, Transactions of the Royal Society of. Vol. xvi. part 5, and vol. xix. part 1. France, Société Géologique de, Bulletin. Deux. Série, tome iv. f. 87-92; t. 6. f. 19-26. DONATIONS. 99 Genéve, Mémoires de la Société de Physique et d’ Histoire Naturelle de. Tome xi. partie 1, and supplements | and 2. Geographical Society (Royal), Journal of the. Vol. xix. part 1. Horticultural Society, Transactions of the. Second Series, vol. 1. parts 3, 4, 5, 6 and 7; vol. 11. parts 1-6, and vol. i. parts 1, 2, 3. Journal of, vol. 11. parts 3, 4, and vol. iv. parts 1, 2, 3. London, Edinburgh, and Dublin Philosophical Magazine. Nos. 233- 237. Mauritius, Transactions of the Royal Society of Arts and Sciences of. Vol. i. parts 1 and 2. Paleeontographical Society, Monographs published by the. Of the Fossil Reptilia of the London Clay, Part |. Chelonia, by Pro- fessors Owen and Bell. Of the Eocene Mollusca, by F. E. Edwards, Part 1. Cephalopoda. Paris, Academy of Sciences of. Comptes Rendus. Nos. 1-24 and 26. Tome xxvii. Prem. Sém. ; index to tome xxvii., and tome xxix. Deux. Sém., nos. 2-14. Royal College of Surgeons, List of Fellows and Members of, for 1849. Royal Society, Philosophical Transactions of the. 1846, part 4 ; 1847, parts 1 and 2; 1848, parts] and 2; 1849, part 1. Pro- ceedings, nos. 66-72. List, Nov. 1848. President’s Address, June 1848. Smithsonian Contributions to Knowledge, vol. i., Reports, &c. 1849. Van Diemen’s Land, Royal Society of, Papers and Proceedings, vol. 1. part 1. ‘Report for 1848. Rules, &c. for 1848. Zoological Society, Reports of the Council and Auditors of, 1849. II. GEOLOGICAL AND MISCELLANEOUS BOOKS. Names in italics presented by Authors. Austin, Thomas. Monograph of Recent and Fossil Crimoidea. No. 8. Buch, L.von. Betrachtungen tuber die Verbreitung und die Grenzen der Kreide-Bildungen. Carter, H. J. A descriptive account of the Freshwater Sponges in the Island of Bombay. On Foraminifera in Arabia, Surdh, &c. Dana, J. D. Synopsis of the Genera of Gammaracea. Conspectus Crustaceorum, &c. Fairbairn, W. An Account of the Construction of the Britannia and Conway Tubular Bridges. 100 DONATIONS. Forbes, J. D. Travels through the Alps of Savoy and other parts of the Pennine Chain, with a Map of the Mer de Glace. Garner, R. ‘The Natural History of the County of Stafford. Goppert, Prof. Uebersicht der Arbeiten und Veranderungen der Schlesischen Gesellschaft fiir vaterlandische Kultur im Jahre 1848. Guyot, Prof. d. The Karth and Man. Hutton, Capt. T. Notes on the Geology and Mineralogy of Aff- ghanistan. (2 copies.) Apparent Objections to the Glacial Theory. (2 copies.) Johnson, J. F. H. Contributions to Scientific Agriculture. Kutorga, Dr. S. Ueber die Siphonotretzeee und eimige Baltisch-Silu- rische Trilobiten. Logan, J. R. The Rocks of Pulo Ubrio. The Languages of the Indian Archipelago. Logan, W. H. Geological Survey of Canada, Report of Progress for the year 1847-48. Mantell, G. A., LL.D. Observations on the Osteology of the Iguanodon and Hylzeosaurus. Newbold, Capt. Summary of the Geology of Southern India. Part 11. Pattison, S. R. Chapters on Fossil Botany. Quetelet, 4. Sur le Climat de la Belgique. ‘Trois. partie. Reid, Iieut.-Col. W. The Progress of the Development of the Law of Storms, and of the Variable Winds, &e. Review of “ Statistics of Coal,” by R. C. Taylor. From Edin. Review, Oct. 1849. Presented by William H. Fitton, M.D., F.G.S. Unger, Prof. Plates 1 and 2 of the Tableaux Physionomiques de la Végétation des diverses périodes du monde primitif. THE QUARTERLY JOURNAL OF THE GEOLOGICAL SOCIETY OF LONDON. PROCEEDINGS OF THE GEOLOGICAL SOCIETY. NovEMBER 7, 1849. The following communications were read :— 1. Remarks on the Genus NERIN&%A, with an Account of the Species found in Portucau. By Daniex SuHarpg, Esq., F.G.S. Tue genus Nériné was proposed by M. Defrance, im the ‘ Diction- naire des Sciences Naturelles,’ for certain species of turreted univalves found among the oolites, distinguished by having both the columella and the interior of the outer lip furnished with folds which are con- tinued through the whole of the whorls; but as M. Defrance had not then seen any perfect specimens, he did not give any strict defi- nition of his new genus. M. Deshayes gave definite characters to the genus under the name of Nerinea, in the ‘ Coquilles caractéristiques des Terrains,’ p. 203, the principal poits of which are the mouth subquadrangular ? cana- liculated ; a broad umbilicated columella with strong spiral folds ; and one or more folds on the interior of the outer lip. ‘Thus far the genus presents well-defined limits; and if we omit the perforation of the columella from its distinctive characters, it consists of a natural group of species. But succeeding authors VOL. VI.—PART I. I 102 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Nov. 7, have broken through all the boundaries of the genus laid down by M. Deshayes, and admitted many species which do not come under his definition of Nerinea. Voltz, who has added largely to our knowledge of the species, includes in Nerinea shells with a rhom- boidal mouth and at least one internal fold (Jahrbuch, 1836, p. 538), thus admitting N. grandis and N. depressa, which have only a fold on the columella, and have the outer lip simple: in this he is fol- lowed by Bronn, and practically also by Goldfuss, who, while de- fining the genus as having folds both on the columella and the outer lip, places in it NV. pyramidalis and N. subpyramidalis with only a fold on the columella. M. d’Hombres-Firmas and M. d’Orbigny have since added N. brevis, a shell without any internal fold what- ever. M. d’Orbigny* has given a full description of the mouth of Neri- nea provided with an anterior and a posterior canal, and has pomted out that in this genus the whorls increase rapidly in size while the shell is very young, and afterwards continue of nearly the same dia- meter: this gives all the species of Nerinea a certain general resem- blance, by which they are easily recognised ; and it follows from this peculiarity that the old shells are nearly cylindrical when the columella is solid, and that in the species of pyramidal form the in-. crease in diameter is obtained by leaving a conical umbilicus down the columella. The remarkable thickening of the internal folds in the upper part of the shell has been frequently noticed: in some species the animal continued to add calcareous matter to these folds till they nearly filled the upper whorls, which then appear to have been abandoned and perhaps to have decayed and worn off ; among the larger cylin- drical species of Nerina we rarely find an old shell with its spire perfect. Most of the shells which have been placed by different authors in the genus Nerinea are so closely connected together, that they ob- viously belong to one group, which unites the rhomboidal opening of the Trochi to the two canals of the mouth of the Cerithia, thus form- ing a link between those genera; and of which the nearest living ana- logue is the Cerithium telescopium, formed by De Montfort into the genus Telescopium. Yet this group now contains shells of such dif- ferent characters that it has. become desirable to divide it either into separate genera or sections. The species admit of arrangement im four natural divisions, which may be regarded for the present as subgenera, and may be defined as follows : Subgenus 1. NERIN#EA. Columella with two or three folds ; outer lip with one or two folds ; the folds all simple; the columella solid or umbilicated. This division contains the typical umbilicated species of Defrance and Deshayes; but it cannot be limited to the umbilicated species * Paléontologie Francaise, Terrains Cretacés, vol. ii. p. 72. 1849. | SHARPE ON THE GENUS NERIN/A. 103 only, as the perforation of the columella is not accompanied by any other constant character, and the umbilicated and non-umbilicated species can hardly be distinguished; moreover N. Voltzii of Des- longchamps has the columella solid when young and perforated in its older stages. More than half the known species of Nerinea fall into this division. Fig. 1 is the section of a portion of N. Archimedis, D’Orb., from near Cintra, which illustrates the internal characters of this sub- genus. Subgenus 2. NERINELLA. Columella solid, either simple or furnished with one fold; the outer lip with one internal fold; folds simple; the mouth usually much longer than wide; the shell nearly cylindrical or very taper. The species of this section are not numerous; they have not the characters laid down by the founders of the genus, but are obviously closely related to it: they are usually small and very elongated. Fig. 2 represents a section of part of VV. Dupiniana, D’Orb., copied from the ‘ Paléontologie Frangaise’ to illustrate this subgenus. Subgenus 3. TROCHALIA*. Columella umbilicated, with one fold; mouth rhomboidal; the outer lip either simple, or thickened internally, or furnished with one internal fold; folds simple; the shell usually short and co- nical. These species differ widely from the original type of the genus, and approach the Trochi; they are usually of large size, without any * Named from its resemblance to Trochus. Tpoyadia, a water-wheel. 12 104 PROCEEDINGS OF THE GEOLOGICAL society. [Nov. 7, ornament, and of a conical or pyramidal form, with a wide umbilicus : they are not numerous. Fig. 3 shows the section of the interior of V. grandis, Voltz, from Alenquer, belonging to this group. Subgenus 4. Pryemartis*. Columella either solid or umbilicated, usually with three folds ; outer lip with one to three folds; one or more of the folds of a com- plex form, either dividing into two lobes, or wider towards the edge than at the base. If we only looked to the number and position of the internal folds, the species of this division would be united to the true Nerinee of the first section; but they form a very natural group, distinguished by the complicated form of the folds, which, instead of bemg enlarged by deposits of shelly matter along their base and sides, as in the other three sections, were principally enlarged towards their edges: in the upper whorls this enlargement of the folds was carried on to such an extent that they nearly fill up the interior of the shell, and leave a narrow passage of a most complicated form for the body of the animal, which gives a very whimsical appearance to the sections of the shells. Externally the shells are of a taper or nearly cylin- drical form, with very little ornament, and the species can only be distinguished conveniently by a section. Fig. 4 shows a section of V. Bruntrutana, Thurm., from Alenquer, to illustrate this subgenus. The following lists contain all the well-defined species of Nerinea, of which descriptions have been met with, arranged under their respect- * From wrvypa, a fold or plait. 1849. | SHARPE ON THE GENUS NERINZA. 105 ive subgenera; and alist is added of shells which have been placed in this genus, but which it is conceived belong to other genera. Subgenus 1. NerRInma. Columella with two or three folds; outer lip with one or two folds ; folds all simple. A. Columella solid. a. One fold inside the outer lip ; two folds on the columella. N. Archimedis, D’Orb. T. Cret. t. 158. f. 3, 4. N. Aunisiana, D’Orb. T. Cret. t. 160. f. 8, 9. N. Bronnii, Goldf. t. 177. f. 4. N. Carteroni, D’Orb. T. Cret. t. 160. f. 1, 2. N. Chamouseti, D’Orb. T. Cret. t. 159. f. 1, 2. N. cingenda, Phillips, G. Yorksh. vol. 1. t. 11. f. 28, 29. N. clavus, Deslongch. Mém. Soc. Linn. Norm. 7. t. 8. f. 28, 29; N. Goodhalli, Deslongch. l. c. t. 8. f. 25; not of Sowerby. N. fi- bula, Deslongch. J. c. t. 8. f. 26, 27. N. Coquandiana, D’Orb. T. Cret. t. 156. f. 3, 4. N. cylindrica, Voltz et Bronn, Jahrb. 1836, p. 542. t. 6. f. 16. N. cylindrica, Deslongch. ; vide N. funiculus. N. Hichwaldiana, D’ Orb. Géol. Russie et ?Oural, 2. t. 37. f. 7. N. elegans, Thurmann, Porrentr. 17; Voltz et Bronn, Jahrb. 1836, po42.t.6.-4, 20. N. elongata, Voltz et Bronn, Jahrb. 1836, t. 6. f. 15. N. Espaillaciana, D’Orb. T. Cret. t. 164. f. 2. N. gigantea, D’ Hombres-Firmas, Mém.; D’Orb.T.Cret. t.158. f. 1,2. N. Goodhallii, Sow. Tr. Geol. Soc. 2nd ser. 4. t. 23. f. 12. N. su- prajurensis, Voltz et Bronn, Jahrb. 1836, t. 6. f. 3, not f. 2; Coldf. t. 175. f. 10. N. involuta, Bronn, Jahrb. 1836, t. 6. f. 25. N. lobata, D’Orb. T. Cret. t. 160. f. 3. N. nodulosa, Desh. Exp. Morée, t. 26. f. 6, 7. N. nodulosa, Deslongech. Mém. Soc. Linn. Norm. 7. t. 8. f. 23, 24; not of Deshayes. N. punctata, Broun, Jahrb. 1836, t. 6. f. 23. N. Remeri, Philippi, Jahrb. 1837, t. 3. f. 1, 2; Goldf. t.176. f. 5; anne fusciata, Roemer ? N. simplex, Desh. Exp. Morée, t. 26. f. 4, 5. N. speciosa, Bronn, Jahrb. 1836, p. 560. N. subteres, Goldf. t. 175. f. 6. N. suprajurensis *, Voltz, sp.; Bronn, Lethea, t. 21. f. 12; Voltz et Bronn, Jahrb. 1836, t. 6. f. 2, not f. 3. MN. Defrancii, Desh. Exp. Moreée, t. 26. f. 1,2; anne N. Archimedis, D’Orb.? * Voltz and Bronn have confounded two species under the name of NV. supra- jurensis: their fig. 3 is the N. Goodhallii, Sow.; fig. 2 appears to be the same as N. Defrancii, Desh., and possibly as N. Archimedis, D’Orb.: without seeing the Specimens it would be dangerous to speak positively. D’Archiac’s shell appears to be different from both. 106 PROCEEDINGS OF THE GEOLOGICAL society. [ Nov. 7, N. suprajurensis, D’ Archiac, Mém. Soc. Géol. de France, vol. 5. t. 30. fto! N. terebra, Ziet. t. 36. f. 3; Goldf. t. 175. f. 13. N. Titan, nobis, t. 12. f. 3. b. One fold inside the outer lip ; three folds on the columella. N. bicincta, Bronn, Jahrb. 1836, t. 6. f. 14. N. flexuosa, Sow. Trans. Geol. Soc. 2nd ser. 3. t. 38. f. 16; Bronn, Jahrb. 1856)-t.6, dO Goldin. 17 fet N. funiculus, Deslongch. Mém. Soc. Linn. Norm. 7. t. 8. f. 30-32. N. acicula? D’ Archiac, Mém. Soc. Géol. de France, vol. 5. t. 30. f.6, 7. N. cylindrica, Deslongch. J. c. t. 8. f. 33; not of Voltz. N. incavata, Bronn, Jahrb. 1836, t. 6. f. 22. N. nobilis, Goldf. t. 176. f. 9; post, t. 12. f. 1. N. nodosa, Voltz et Bronn, Jahrb. 1836, p. 542. t. 6. f. 9. N. Pailletteana, D’Orb. T. Cret. t. 161. f. 1-3. N. pauperata, D’Orb. T. Cret. t. 161. f. 6, 7. N. regularis, D’Orb. T. Cret. t. 160. f. 10. N. Requieniana, D’Orb. T. Cret. t. 163. f. 1-3. N. subscalaris, Goldf. t. 175. f. 12. N. trinodosa, Voltz et Bronn, Jahrb. 1836, p. 540. t. 6. f. 10. c. Two folds inside the outer lip; three folds on the columella. N. ampla, Goldf. t. 176. f. 10. N. Podolica, Pusch, Poln. Pal. t. 10. f. 17; Bronn, Jahrb. 1836, t-0.°% V1. N. teres, Goldf. t. 176. f. 3. N. uchauxiana, D’Orb. T. Cret. t. 164. fs B. Columella umbilicated. a. One fold inside the outer lip ; two folds on the columella. N. Geinitzii, Goldf. t.177.f.8. NN. Borsoni, Geinitz, Sachs. Kreide- geb. t. 14. f. 6, 7; Roemer, Kreidegeb. t. 11. f. 8. N. Renauzxiana, D’Orb. T. Cret. t. 157. N. Sequana, Thirria, p. 7; Voltz et Bronn, Jahrb. 1836, t. 6. f. 6; Goldt a> LAG ae g N. Visurgis, Roemer, Ool. t. 11. f. 26, 28; Voltz et Bronn, Jahrb. 1836, t. 6. f. 8; Goldf. t. 176. f. 6. N. Voltzti, Deslongch. Mém. Soc. Linn. Norm. 7. t. 8. f. 34. b. One fold inside the outer lip ; three folds on the columella. N. Bauga, D’Orb. T. Cret. t. 162. f. 1, 2. N. bicincta, Bronn, Jahrb. 1836, t. 6. f.14; Goldf. t. 177. f. 5 ;—is this umbilicated ? N. elegans. Helicoceras, sp. Koenig, Icon. Sect. 249. N. grandis, Goldf. t. 175. f. 8; not of Voltz and Bronn. c. Two folds inside the outer lip; three folds on the columella. N. Mose, Desh. Coq. Caract. t. 4. f. 1, 2. 1849. | SHARPE ON THE GENUS NERINAA. 107 C. Internal structure imperfectly known. N. Borsom, Catullo sp. Bronn, Jahrb. 1836, t. 6. f. 12. N. cincta, Goldf. t. 177. f. 12. N. dubia, D’ Archiac, Mém. Soc. Géol. France, 2nd ser. vol. 2. t. 25. al N. excavata, Brongniart sp. Env. Paris, t.9.f.10. Turritella con- cava, Sow. Min. Conch. t. 565. f. 5. N. Gose, Roemer, Ool. t. 11. f. 27; Bronn, Lethea, t. 21. f. 11; Goldf. t. 175. f. 9. NN. margaritifera, D’ Archiac, Mém. Soc. Géol. de France, vol. 5. teo0. £24), N. suleata, Ziet. t. 36. f. 4. N. tuberculosa, Roemer, Ool. t. 11. f. 29. N. turritellaris, Goldf. t. 177. £. 3. N. unicarinata, Woodward sp. Geol. Norf. t. 6. f. 21. Subgenus 2. NERINELLA. Columella solid, either simple or with one fold ; outer lip with one internal fold; mouth longer than wide; shell taper or nearly cylin- drical. A. Columella simple. N. Matronensis, D’Orb. T. Cret. t. 159. f. 9, 10. N. subequalis, D’Orb. T. Cret. t. 162. f. 5, 6. B. Columella with one fold. N. constricta, Roemer, Ool. t. 11. f. 30; Bronn, Jahrb. 1836, t. 6. i Goldf, t. 175. 1. 11. N. Dupiniana, D’Orb. T. Cret. t. 159. f. 5-8. N. granulata, Goldf. t. 177. f. 6. N. quadricincta, Goldf. t. 176. f. 4. C. Internal structure imperfectly known. N. fasciata, Roemer, Ool. t. 11. f. 13; Voltz et Bronn, Jahrb. 1836, tate te 21: N. pulchella, D’Orb. T. Cret. t. 161. f. 4, 5. N. Royertana, D’Orb. T. Cret. t. 159. f. 3, 4. N. subcochlearis, Goldf. t. 175. f. 14. Subgenus 3. TROCHALIA. Columella umbilicated with one fold; outer lip either simple or with one internal fold; shell usually conical. A. Outer lip straight and simple. N. depressa, Voltz et Bronn, Jahrb. 1836, t. 6. f. 17. N. pyramidalis, Goldf. t. 176. f. 11. N. subpyramdalis, Goldf. t. 175. f. 7. 108 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. | Nov. 7, B. Outer lip deeply depressed in the middle and thickened internally. N. annulata, nobis, t. 13. f. 1. . N. grandis, Voltz et Bronn, Jahrb. 1836, t. 6. f.1; not of Goldfuss. C. Outer lip furnished with an internal fold. N. turbinata, nobis, t. 12. f. 2. Subgenus 4. Pryemartis. Columella usually with three folds; outer lip with one to three folds; one or more of the folds of a complex form, either dividing into two lobes, or wider towards the edge than at the base. A. Columella solid. N. bifurcata, D’Orb. T. Cret. t. 160. f. 4, 5. N. Conimbrica, nobis, t. 13. f. 4. N. Eschwegii, nobis, t. 13. f. 2. N. Fleuriausa, D’Orb. T. Cret. t. 160. f. 6, 7. N. Olisiponensis, nobis, t. 13. f. 3. NV. triplicata, Voltz et Bronn, Jahrb. 1836, t. 6. f. 24. B. Columella umbilicated. N. Bruntrutana, Thurm. 17; Bronn, Lethea, t. 21. f.13; Voltz et Bronn, Jahrb. 1836, t. 6. f. 13, 18; Goldf. t.175.f.5. WN. hiero- glyphica, Lyell, Elem. Geol. 2. p. 48. f. 246. N. Bruntrutana, D’ Archiac, suet Soc. Géol. de France, vol. 5. t. 30. eas bil N. crenata, Goldf. t. 177. f. 2. N. imbricata, Desh. Exp. Morée,.t. 26. f. 4, 5. N. Mandelslohi, Bronn, Jahrb. 1836, t. 6. f. 26; Goldf. t. 175. f. 4. N. trachea, Deslongch. Mém. Soc. Linn. Norm. 7. t. 11. f. 2, 3. N. Voltzti, D’ Archiac, Mém. Soc. Géol. de France, vol. 5. t. 30. f. 5; not of Deslongchamps. The following species, which have been placed in Nerinea, appear to belong more properly to other genera :— N. brevis, D’ Hombres-Firmas ; D’Orb. Terr. Cret. t. 162. f. 3, 4; has no internal fold, nor the mode of growth of the Nerinee: as only a cast has been figured it is difficult to decide on its true genus, which may be Trochus or Pleurotomaria. N. Marrotiana, D’Orb. T. Cret. t. 163 bis, f. 1, 2, has the folds on the columella only formed at certain intervals, as in Pyramidella. N. monilifera, D’Orb. T. Cret..t. 163. f. 4, has only a fold on the top of the whorl, with the columella and the outer lip simple, as in Telescopium. N. perigordina, D’Orb. T. Cret. t. 163 bis, f. 1, 2, belongs to Ce- rithium, having the outer lip simple,.and a fold on the columella, which, according to the figure, is not contmued through the whorls. 1849. | SHARPE ON THE GENUS NERINAA. 109 N. pulchella, Thurm. Porrentr. 17, is a Cerithium according to Voltz and Bronn, Jahrb. 1836, p. 566. N. quinquecincta, Goldf. t. 176. f. 2; probably a Cerithium? N. tricincta, Goldf. t. 176. f£. 1, is a Cerithium. N. turritella, Goldf. t. 176. f. 5, is also a Cerithium: these two last have only a fold on the columella, which may be seen in C. gi- ganteum, C. cornucopie, &c. continued throughout the spire. The fossil remains of Nerinea are usually found in company with corals, Ostraeze, Pectens, and other shells supposed to have been natives of shallow seas; and rarely near many Terebratule or Ammonites. It is probable, therefore, that they were littoral animals. They are most common in beds of limestone, are seldom seen in sandstones, and still more rarely in clays. In England we have in the different beds of oolite many species of Nerinea, but only one, N. Goodhalli, which attams a considerable size; and there are only one or two very small species known in the cretaceous system. In the North of Germany, according to Reemer, the oolitic series furnishes several species of Nerinea of middling size; but only one species is known in the greensand, and none in the chalk. In the South of Germany, Voltz and Goldfuss have published several large and small species both from the oolitic and the creta- ceous systems. In France the oolitic species of Nerinea are large and numerous, but they have been but imperfectly described. M. D’Orbigny’s ‘ Paléontologie Francaise’ gives us full information of the distribution of the cretaceous species. There have been eleven species found in the subcretaceous beds, of which the six from the basin of Paris are small or of middling size, while all the five found in the South of France are very large: the fifteen species found in the Crate chloritee are all from the South of France, only one reaching as far north as the Loire ; some of these are large, but they do not equal in average size the subcretaceous species from the same districts. None have been found in France in the upper chalk. In Portugal I met with no Nerinee in beds of the oolitic period ; but these beds appear to have been deposited in deep seas ; and more- over, my examination of them was too slight to found anything on this merely negative evidence. In the beds classed as subcretaceous the species of Nerinea are numerous, and many reach a very large size. From the hippurite limestone, which is of the age of our chalk, and which I examined very thoroughly, I have three species, the largest of which is only of moderate size. It thus appears that the period most favourable to the development of Nerinee was that of the oolites in the North, and that of the greensand in the South of Europe. Comparing together the species found im different formations of any one country, we find the species of the older formation more numerous and on the average larger than those of the more modern formation. But on comparing the Nerinee found in the same formations in 110 PROCEEDINGS OF THE GEOLOGICAL society. |[Noyv. 7, different latitudes, we find that in each instance the average size of the species is larger in the south than in the north. If it might be assumed that the species of Nerinea reached a larger average size in warm than in cold climates, which is probable from what we know of the recent genera nearest to them in organiza- tion, two conclusions might be drawn from the preceding remarks: Ist, That in each of the epochs referred to, there was a similar differ- ence between the climates of the North and South of Europe to that which now distinguishes them; 2ndly, That in each of the districts mentioned the temperature was gradually falling through the periods of the deposition of the oolitic and cretaceous series of beds. The first conclusion is in itself so probable that it will be readily accepted ; the second must be substantiated by similar results drawn from the comparison of a large series of both animal and vegetable remaims before it can be admitted. In confirmation, however, of the latter conjecture, we find certain species of Nerinea in the South of Europe in beds of a later period than those in which they are found in the North. Thus N. Brun- trutana, N. grandis (of Voltz, not of Goldfuss), and NV. cylindrica, which near Lisbon are found in limestones of the subcretaceous pe- riod, occur in France and Germany either in the Portland oolite or the Kimmeridge clay ; and NV. nobilis, which occurs in a bed near Lisbon corresponding to our upper chalk, is found at Salzburg in the greensand. But I can find no contrary instance of a species occurring in the South in an older formation than in the North of Europe. On some future occasion I shall show that species of other genera of Mollusca which are in the North of Europe confined to the oolitic formations lived on during the deposition of the cretaceous rocks of Portugal, and I will at the same time explain the grounds on which the classification of the Portuguese beds has been adopted. The facts seem to point out that the seas which covered Portugal durmg the cretaceous period had a temperature which in the latitude of England only existed durmg the deposition of the oolites; and this might be the case if the temperature of these parts of the globe was gradually falling. But I repeat that I am far from thinking these observations sufficient to prove so important a doctrine, and I only regard them as very slight evidence tending in that direction, and which may be confirmed or contradicted by further inquiries. The following species of Nerinea have been found in Portugal :— Subgenus 1. NERINZA. N. nobilis, Goldf. t.177. f.9; post, t. 12. f. 1; common in the upper beds of the hippurite limestone near Lisbon. N. Archimedis*, D’Orb. T. Cret. 2. t. 158. f. 3, 4 ; m suberetaceous limestone in the cliffs at the Praia de Adrarga near Cintra. * Perhaps N. Archimedis may be identical with N. suprajurensis, Voltz and Bronn, Jahrb. 1836, t. 6. f. 2 (not f. 3), and with N. Defrancii, Desh., but I have, in the doubt, adopted M. D’Orbigny’s name, as the Portuguese shell agrees best with his figure. 1849. ] SHARPE ON THE GENUS NERINAA. 1A N. cylindrica, Voltz and Bronn, Jahrb. 1836, t. 6. f. 16; in sub- cretaceous limestone at Sarjento-mor, six miles north of Coimbra, and in the cliffs at the Praia de Adrarga near Cintra. N. gigantea, D’ Hombres-Firmas, Mem.; D’Orb. Terr. Cret. 2. t.158. f.1, 2; m subcretaceous limestone at Alenquer. N. Titan, nobis, t. 12. f. 3; in suberetaceous limestone in the cliffs at the Praia de Macams near Cintra. Subgenus 3. TROCHALIA. N. annulata, nobis, t.13.f.1; in subcretaceous limestone at Alenquer. N. grandis, Voltz and Bronn, Jahrb. 1836, t. 6. f. 1; im subcreta- ceous limestone at Alenquer. N. turbinata, nobis, t. 12. f. 2; im subcretaceous limestone between Sobral and Torres Vedras, and three miles south-west of Alenquer. Subgenus 4. PryGmartis. N. Eschwegii, nobis, t. 13. f. 2; m the upper beds of the hippurite limestone near Lisbon. N. Olisiponensis, nobis, t. 13. f. 3 ; in the upper beds of the hippu- rite limestone near Lisbon, and in subcretaceous limestone at the Praia de Macams near Cintra. N. Bruntrutana, Thurmann ; Voltz and Bronn, Jahrb. 1836, t. 6. f.13 & 18; Goldf. t. 175. f. 5; im subcretaceous limestone at Alenquer. N. Conimbrica, nobis, t. 13. f. 4; im subcretaceous limestone at Sar- jento-mor, six miles north of Coimbra. Description of the Species. Subgenus 1. Nerina. NERINZA NOBILIS, Goldfuss, t. 177. f. 9. Shell turreted, smooth, conical when young, cylindrical when old. Whorls numerous, very slightly convex, increasing slowly in size. Suture running along a faint depression. Mouth elongated, with a fold near the top of the outer lip and three folds on the columella. Columella solid, nearly equal in thickness to one-fourth of the dia- meter of the shell. Four simple folds in the interior, of which one on the outer lip projecting half across the whorl in a slope parallel to the base of the whorl ; two on the columella, of which the upper one is the smaller, and nearly opposite to that on the outer lip; and one small fold on the top of the whorl sloping outwards. Spiral angle irregular, about 15° in the young, hardly perceptible im the old shell. Sutural angle varying with the age from 100° to 110°. Basal angle* varying between 120° and 130°. Usual dia- meter of old shells from #ths to 1 inch, rarely 14 inch. Very abundant in the upper beds of the hippurite limestone near Lisbon. * T have used the term Jasal angle for the angle formed by the meeting of the side and base of the whorl. In this genus it furnishes a character by which many species otherwise similar externally may be distinguished. 112 PROCEEDINGS OF THE GEOLOGICAL SOUIETY. _[Nov. 7, I refer my shell to N. nobilis with some hesitation, because it never reaches the size of the specimen figured by Goldfuss from Salz- burg, and it is only m its younger state that it has the pupoidal form of his species. Before reaching half the diameter of his specimen the Portuguese shells have usually become nearly or quite cylindrical ; still I can find no distinctive characters upon which to found a new species. Most of the specimens found at Lisbon are internal casts, and neither in that state nor in the section can they be distinguished from N. nodosa of Voltz, with which I confounded them till specimens were found. covered with the shell: the latter species has not been found at Lisbon. In the casts each whorl appears deeply divided into two rings ; in the young shell, fig. 1 6, the lower ring is narrower and rounder than the upper ; but in older shells, fig. 1 ¢, the two rings are nearly equal, and in this state the casts resemble those of V. Bor- soni, which may perhaps be the same species. Puate XII. fig. 1 a. Exterior of a young shell. Fig. 1 6. Cast of a young shell. Fig. 1 c. Cast of an old shell. Fig. 1 d. Section of a shell nearly full-grown. NeERINZA TITAN, 0.8. Shell turreted, smooth, conical when young, cylindrical when old. Whorls very numerous, deeply concave in the middle ; equal in height to one-third of the diameter of the shell; hardly increasing in size in the old shell. Suture in the middle of a broad high ridge. Mouth nearly square. Columella solid, occupying one-fifth of the diameter of the shell. Three folds in the interior, of which one on the middle of the outer lip has a broad base and sharp edge projecting but little ; one on the columella slightly below the former projects thin and sharp beyond the middle of the whorl; one on the top of the whorl, sharp and smaller than the last, and curving outwards. Sutural angle about 85° when young, 95° to 100° when old. Basal angle 105°. Spiral angle in young shells about 20°; when old the shell is so nearly cylindrical that in a fragment 5 inches long the dia- meter only increases one-eighth of an inch. Greatest diameter 2% inches. Very abundant in the limestone beds of the subcretaceous series in the cliffs north of Cintra, especially at the Praia de Macams, where a bed several feet thick is entirely formed of the debris of these shells. This species resembles NV. gigantea, which it fully equals im size, but it is readily distinguished by a flatter base to the whorl and squarer mouth, and by the two inner plaits projecting farther inwards ; it 1s also closely related to NV. Goodhalli. Prate XII. fig. 3a. Exterior. Fig. 3 6. Section. Subgenus 3. TROCHALIA. NERINZA ANNULATA, 0. 8. Shell conical, smooth, with projecting broad rings: spiral angle 25°, regular. Whorls numerous, deeply concave, one-fourth as long as they 1849. | SHARPE ON THE GENUS NERINAA. 1t3 are wide, increasing regularly. Suture in the middle of a rounded ridge, which is broader than the concavity of the whorl. Columella hollow, the umbilicus occupying about one-fourth of the diameter of the shell. Mouth subrhomboidal, with the outer lip indented. One fold in the interior, on the top of the whorl, curving outwards. Sutural angle 85°. Basal angle 100°. Greatest diameter seen 12 inch. Found in limestone near the base of the subcretaceous series at Alenquer. Readily known by the regular annulations of the exterior, and by the single fold at the top of the nearly square interior of the whorls, in which it resembles NV. depressa, N. pyramidalis, and N. subpyra- midalis. Puate XIII. fig. 1 a. Exterior. Fig. 1 6. Section. NERINAA TURBINATA, 0. S. Shell conical, with a large umbilicus. Spire increasing regularly with an angle of about 35°; whorls about ten, concave in the middle and crossed by slightly oblique irregular lines of growth. Suture in the middle of a projecting ridge which is irregularly crenulated by the Imes of growth. Mouth subrhomboidal, with a callosity inside the outer lip and a fold on the inner lip. Columella hollow, the umbili- cus occupying one-third of the diameter of the shell. Two folds in the interior; one on the middle of the outer lip, the other a little below it on the columella. In the lower whorls the folds are nearly equal, and a section of the space left is a rude representation of an hour-glass ; in the upper whorls the outer fold becomes much larger than its fellow. Sutural angle about 90°. Basal angle about 95°.‘ Total length 13 inch. Diameter 3 of an inch. Found in limestone near the base of the subcretaceous series three miles south-west of Alenquer, and between Torres Vedras and Sobral. In external form and markings this shell so exactly resembles Trochus Astierianus of D’Orbigny, Terr. Cret. pl. 176. f. 16, 17, that they might easily be confounded ; but the latter species is figured without an umbilicus, and is described as not umbilicated (p. 182). Our species is allied to V. Renauaiana, D’Orb., by its hollow colu- mella, and it resembles the young state of that species in its spiral angle ; but it has a fold less on the columella. About twenty speci- mens have been seen, all so nearly of the same size that they may be presumed to be full-grown shells. Prats XII. fig. 2 a. Exterior. Fig. 2 6. Section of the interior of another specimen. Subgenus 4. PryGMartis. NerRinzA ESCHWEGII, 0. Ss. Shell turreted, cylindrical, smooth. Whorls numerous, nearly equal, convex, equal in height to half the diameter of the shell. Suture running in a marked depression. Columella solid, small. — 114 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Nov. 7, Four folds in the interior reducing the hollow of the whorl to a very narrow complicated passage ; viz. two folds on the columella, of which the upper is thin and very small, the lower larger, with a wide base which rapidly decreases to a thin edge and is again thickened at the extremity ; one large fold on the top of the whorl with a wide base, curving outwards and thickened at its extreme edge, and one fold on the outer lip thickened at its edge. Besides these four folds there is a callosity at the top of the whorl near the outer lip and another at the base of the whorl. Sutural angle between 95° and 100°. Basal angle 110°. Rare in the hippurite limestone near Lisbon. Closely allied to N. Olisiponensis, this species may be recognised by its cylindrical form, deep sutural depression, and by a more com- — plicated internal structure. I have named this shell after the Baron d’ Eschwege, the first geo- logist who seriously attempted to work out the series of Portuguese formations, and to whose kindness I have been largely indebted for assistance and information during my visits to Portugal. Puate XIII. fig. 2 a. Exterior. Fig. 2 6. Section of the same specimen. NERINZA OLISIPONENSIS, 0. S. Shell turreted, slightly conical, smooth ; spire increasing slowly ; spiral angle 10° in the young, 5° in the old shell. Whorls very numerous, smooth, with straight sides and nearly flat below, separated by a well-marked suture. Columella solid, small. Four folds in the interior, which reduce the hollow to very narrow dimensions of a most complicated form, viz. two folds on the columella, of which the upper is small and sharp, the lower prominent and thickened at the extre- mity ; one strong sharp fold on the outer lip, and one long thin fold on the top projecting outwards a curve. Besides these there is a faint ridge along the top of the whorl close to the outer lip. Sutural angle between 90° and 95°. Basal angle about 100°. Greatest diameter observed 1 inch. Found in the hippurite limestone at Lisbon and in the subereta- ceous limestone at the Praia de Macams north of Cintra. Prate XIII. fig. 3 a. Exterior. Fig. 3 6. Section. NERIN&A CONIMBRICA, 0. S. Shell turreted, slightly tapering when young, nearly cylindrical when old, almost smooth. Whorls very numerous, increasing slowly in size; very slightly convex, faintly marked with oblique lines of growth. Suture marked by two delicately impressed lines. Mouth subrhomboidal, with one strong fold on the outer lip and two long curved folds on the columella. Columella solid, small. Four folds in the interior, which reduce the hollow to a narrow complicated passage ; of these, two folds are on the columella, the lower one longer than the other, and both thickest near the extremity ; one large fold on the outer lip, and one long thin fold on the top curving outwards. Quart. Geol. Journ, VobVE PEALE THOT Oe i RT x) ‘hs : re [ft iy ERLE SDE. Sowerb V fect. , Ww ON dia oct a 5 Te) SOON Quart. Geol. Journ, Vol. VL PLXE. JS be C. Sowerby fect. 1849. | BROWN ON THE SYDNEY COAL-FIELD. Vis Sutural angle about 95°. Basal angle 100°. Greatest diameter 3 of an inch. ! Found in limestone of the subcretaceous series at the village of Sarjento-mér, six miles north of Coimbra. Puate XIII. fig. 4a. Exterior. Fig. 4 6. Internal cast. Fig. 4c. Section. EXPLANATION OF THE PLATES. PLATE XII. Fig. 1. Nerinzea nobilis. Fig. 3. Nerinzea Titan. Fig 2. Nerinza turbinata. PLATE XIII. Fig. 1. Nerinzea annulata. Fig. 3. Nerinzea Olisiponensis. Fig. 2. Nerinea Eschwegii. Fig. 4. Nerinzea Conimbrica. 2. Section of the Lowrr Coat-MEasurses of the SypNEY CoAL- FIELD, in the IsLAND OF Care Breton. By Ricuarp Brown, Esq. [Communicated by the Secretary. | THE coal-measures of Nova Scotia Proper have been carefully exa- mined and described by Sir Charles Lyell. Mr. Logan has also published a ‘‘ Section of the Nova Scotia Coal-Measures, as developed at the Joggins in the Bay of Fundy,” which appears to have attracted much attention; but the Cape Breton coal-fields, im every point of view the most important in British America, appear to have been almost wholly neglected by geologists. I have been for some years engaged in collecting materials for a description of the Sydney coal- field, but seemg no immediate prospect, amidst the engrossing duties of an arduous profession, of completing such an extensive work, I have concluded to submit to the Society a detailed section of the lower part of the productive coal-measures, as developed on the shores of Sydney Harbour, under the impression that it will furnish many valuable facts and data calculated in an eminent degree to elu- eidate the origin of the coal beds, and at the same time to assist geo- logists in institutimg a comparison with the Bay of Fundy section, from which it will be found to differ in at least one very important feature, to which I shall refer more particularly in the sequel. This coal formation, as has been already stated in vol. i. p. 23 of this Journal, consists of the following group of strata :— 4. The productive coal-measures. 3. A thick deposit of sandstone. 2. Limestones and shales, occasionally containing beds of gypsum. 1. A coarse conglomerate. The lowest member of this group (1), the representative probably of the old red sandstone of Europe, crops out from beneath the car- boniferous limestone at the head of the north-west branch of Sydney Harbour, where it consists of thick beds of conglomerate alternating 116 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [ Nov. 7, with red shale. The conglomerate is chiefly composed of fragments of red granite and quartz pebbles, cemented together in a base of ferruginous red clay. Its thickness has not been ascertained. The next member of the group (2) consists of alternating beds of limestone, red and brown shales, and friable micaceous sandstones. No beds of gypsum are visible in this section ; it is only in the neigh- bourhood of the protruded masses of granite and trap that gypsum is met with. The total thickness of this series is 820 feet. Fossils are rare and of few species; the most common are Producta Lyelli, P. spinosa, P. Martini, P. Scotica, Spirifer glaber; and a few un- determined scales of fishes, in one of the upper limestone beds. Some of the shales are finely laminated and rippled. Stigmariee, apparently drifted, as no rootlets are attached to them, occur in a bed of arena- ceous shale in the higher part of the section. The sandstone deposit (3), which is analogous in position to the millstone grit of the English coal-fields, is 1800 feet in thickness. The lower beds are coarse and pebbly; the upper, fine-grained, and often flaggy, containing impressions of Sigillariz, Calamites, and Lepidodendra. A few thin beds of grey shale are interstratified with the sandstones at wide intervals. The productive coal-measures (4) cover an area of 250 square miles, but owing to several extensive dislocations it is impossible to ascertain their total thickness with any degree of accuracy ; from the best information in my possession I conclude that it exceeds 10,000 feet. We have one continuous section on the north shore of Boular- drie Island 5400 feet in thickness, and in the middle portion of the field, several detached sections varying from 1000 to 2000 feet in thickness, whose exact relative positions have not yet been deter- mined, although it is quite clear that they are higher up in the forma- tion than the highest beds of the Boulardrie section. These points can only be ascertained by a careful survey of the whole district ; I therefore propose, as I said. before, to confine my observations at pre- sent to the small portion exhibited in the cliff on the north-west shore of Sydney Harbour. The coal-measures commence at Stubbord’s Point, where they re- pose conformably upon the millstone grit, and terminate at Cranbe Head on the sea-shore; the total length of the section being 5000 yards, and the thickness from actual measurements, taken at right angles to the plane of stratification, 1860 feet. The dip is north 60° E. at an angle of 7°. In the following table the beds are placed in their natural crder, No. 367 being the highest bed at Cranberry Head, and No. 1 the lowest, in contact with the millstone grit at Stubbord’s Point. Section of the Coal-Measures on the north-west shore of Sydney Harbour, in the descending order. No. ft. in. 367 Slaty, SaAWAStONE e20222. casa te siesccawes wene~n osm sp emasameelenee 10 0 366. Soft blue argillaceous shale ...........c.ssceeeeeeetecnceeeoneee 0 6 365. Argillaceous shale containing a few small nodules of iron- stone near the bottom (plants) ...............ssececeeeeneees 4 0 364. Argillaceous shale (plants) .......0.....cseeeseseeeceeneeeeeeeeees 2 1849.] No. 363. 362. 361. 360. 359. 358. 357. 356. 355. 354, 353. 352, 351. 350. 349, 348. 347. 346. 345, 344, 343, 342. 34]. 340. 339. 338. 337. 336. 335. 334. 333. 332. 331. 330. 329. 328. 327. 326. 325. 324. 323. 322. 321. 320. 319. 318. 317. 316. 315. 314. 313. 312. dll. 310. 309. 308. BROWN ON THE SYDNEY COAL-FIELD. ft. (GE Gageetiobhoesueesecasogds 1dacbeeeer sopadboocecusd: codopdoccdeer oo 0 WINer elas (Sea AT A) oe keer eae ce ester ees decease ebeaes 2 PRENACCOUS SIAL (DIAMUS) cpr mincecens «seis ris resticccon caters 3 Coali(Cranberry Head, top Seam) 7.5.2.0... ss. .anevesseeccnees 3 Winclone lenyy (Sis avial)ae AS iee cece ese olnses «valet set daosanatoecs 0 Hard arenaceous shale (Stigmaria) ........-cce.se..sssseeeees 4 Arenaccous shale (plants) js -pcacerrncsoesiereseewesscaaccsacae's 3 Coals (Ot PeESIStENb) messi ss ccanddtensacs-:-ceseecamnceasns 0 Arenaceous shale (plants, erect trees and Stigmaria) ...... 7 NOt Ole Clap sancsnemes see names «sles «n)sfobiciesi« vic oie Slieiacte cel saa Mi 1A Gio be arlaiaenes 022 js clay ...... O72 } (Cranberry Head, bottom seam).. 1 Coalewesss cs: 0 8 WiaderclayA (Stim arta) seve caatoss se eniscace oases desesacn scesine 0 Argillaceous shale with thin carbonaceous layers(Stigmaria) 0 Hard arenaceous shale (Stigmaria) .......00......seeeeeeeeees 2 Strong slaty sandstone (ripple-marks) .................s00e00 2 Sldiye wavilie SaItStONes © ase aaesencdenecussdccnessseqetae 4 Sandstone and argillaceous shale, mixed ..................... 2 Fer OMlACCOUSESHALE™ Bis, sca tacaesoaieeesetenssinnaemaciccncenea les eek 0 Arenaceous shale alternating with sandstones in layers of 2 to 12 inches thick (plants and erect trees)............... Argillaceous shale (plants and erect trees) .............00.. uE Alternating laminz of shale and carbonaceous matter...... 5 Argillaceous shale (ferruginous concretions) ............... 7 /STRSEXGEOS SUE| soon scdGaandcemeceocio codec cocecmobubebio: scancuAce 2 Arenaceous shale, passes into soft sandstone ............... 4 Mixed sandstone and SHAlG 022... vcsse0cieasscedmnsie sareciecaans 7 RUDLLNC LAN eee re etelee cia iaie sais sisw'a.<'¢ s holetcntatus wines Sento wbicasitersa 0 EME D evar oN ACEOUSISNALE | caste decnaradiecjeresc eases i--ssces 1 Pt SULACCOUSESMALC: meni aese sees slice deseansee eer. -orear esas aetons 1 anple are llaCeOUsistale Dire. apace -ceseedesestss aesienaespcredeaer ] Geenishy arena CcOMS SMMC saceranesaseevaccieeecsiazescsac ses etesis 5 Fe ple AnPAMACEOUS SWAIC feces ccc cesiee ce +nodsca scene scoldissese de 0 SS COME Ale MIN MAMI CS Pactene ces a/c) cc's seeesmawante som sdeseieer 8 Red argillaceous shale with thin green layers ............... 8 PARE CEOS SINAC so. cases nanens ocitciamadincelawecastondem qemeumieenen ee receptions 2 BBUE Mel CEOS SMA Ge sty terietsciais see sepes weiss 7 Palsla/s a) a'alstolsjtvelealowiinrae dist 2 ie deat ACEO USIS NM Gr ly crac. canine mance /seera ote semis sesesraaiscs 1 Greenish laminated SamdstONe. 27... .«s-c-wec-cepn es cecesoenncn 14 Red argillaceous shale containing 6 inches of sandstone... 1 lays SAG SOME! cise. asic Maas web, ce dactiahsrsiacies Said tesinwivciaerawe tet 8 ESE ONIN ATOMIACCOUS (SMALE aes. cis «nisin etiteworicnese siemviaegijens 0 Arenaceous shale with four layers of red argillaceous shale ApMINGELValS Of aeteCizets na tcacesc. eusodtaeecee satan: acon eee 25 Slaty sandstone with two thin layers of red shale ......... 9 Intermingled brown, grey, and red arenaceous shales...... ) Prec auetlaceOuUsiS Male) Vsccsse. jeavevcisensenegtants ao scechyeesone 9 PMEECTACEOUS SADC oenciactcate ons «as eoeince ssa cemaninns soaseacase avn: 3 MEISEOME! ce Meee nceh cde eaten os cre ts yoceesceshycmseeese tern 10 Alternating layers of shale and sandstone 1 to 4 inches each 3 SAUSHOMEL deus sessed ane tee vosdsamite dass aceancestaie idennnsens 6 Renmiginous arenaceOus SNAG. oscccn...cersascssncnee dens ocean y) Argillaceous shale containing thin carbonaceous layers ... 0 Pat EMA CEOUSISMRR Ciscoe see cece Pens ea-borbaioranniseiisp sian secesisngs 4 SOMbsCEUMDMMS SANUSCONG cesses ec --cpsrcewenccececnessnraeseoes 2 SieOmce SAG SoONeL( MANES) tcces. cent cngeasdeees cn dcecgse nese 13 EMEP ACCOMS SMALE. cameras ackeeccnaeac tani pas a cemnceeienseee ass 1 Mixed argillaceous shale and impure coal............000...065 0 VOL. VI.—PART I. K — —— =e Nooornocn bole — MBovoFf,ouonoworFoOnoocroosacocoe Aoconrwmnoqgcn So Ooo°cremueroococooen® 118 PROCEEDINGS OF THE GEOLOGICAL society. [Nov. 7, No. ip. Thee 307. Underclay(Stismaria)osccnic sins cckosecscn cen vaseeswoseetacsnast 2 ..Q 306. Mixed argillaceous shale and Coal............cecceceeereeeeeees 1 aG 305. Underelay -(Stigmania)).. satsoncxuscreon tec teves: ioeten coe eeneeee 6 0 304. ‘Argillaceous:shale (plants) .sancs-c- 7.26 coocoeos-ocee contenant 2 V6 303. Argillaceous shale containing small nodules of ironstone (ECE TECES): sccetcnmecias ne sareiwuaees -ctooccenwe tes eaere meneame 0 302. ‘Soft. argillaceots shales <<5.cccsceses~-onsaccscascceeceesecseeaeee 2 6 ft. in. Coal. so-ecncceaene 0 2 301. <4 Soft shale........ OB use ceca cre eile sbremiotianc coco aueece seems tv Coalere-eaeeeecene® 0 3 300. “Underelay (Stiemaria) {j.2.cccccts. ones ceenausdseeeecaaenee eee UBS ie 299. Sandstoue (erect Calamites): 2. -... ne cocceneees conse eee eee 2 4 209. Greenish’ arenaceous shale .........--s9 nasa cenenisninm cn teees.. see aes se 2 Hamunated: sangsbOney (PLANES) iocs-nssresceceeadeaee-maradaneeris. 0 Winderelay (Stismiatial) (srccess «edsecs -aaacesscamemeniebaiakse ar Ze Laminated grey sandstone (ripple-marks) ......ecsssscesees 0 Argillaceous shale containing nodules of ironstone ......... 0 Crumbling arenaceous shale containing large masses of COUELCHORALY SANASKOME occ ce cs -nisinnc dan besmiavene — ante nee res 3 Laminated grey sandstone (Fucoids).........cccscsceeesoeeeees 1 PAVEMACCOUS| SHALE ssioinc seinicislens ns gasnicaaen os depitaseilaneiidmcbas eames 0 Laminated grey sandstone (Fucoids)................2c.sseeeee 1 Mixed sandstone and crumbling arenaceous shale contain- ing large concretionary masses of sandstone ............... 2 PLOT ECOUS SU ALC ao 2c «ocsicivinumpmcn nice as slimline vaisleoige a ciacheae of 2 SlaLVESAWOSLOMEY wi screnmnacicancieeesenroi spnsiacsay ects cincsena teats 1 PREETI CEOS, SIMALE shield aston aniataineidadidew als maken is giceabdorwas i Black bituminous shale (fish-scales, teeth, coprolites and GXUINIE Ol OWLS) icc pep asin aor ecciomepea sateen aan. sce eaesaes 1 Rin ayPMULACE DUS SHALC jocsdanaeastacepins/ tte desssnaiere sere seers 0 Bituminous shale (fish-scales, coprolites, Cypris and Mo- PIMA Pr tattoos islaabl sgaiseseibe ia eisicncjsine Sneerenee ceca teak oars 1 Green ATENACeE OS SHALE) h slanshes aman tiene saree ameteseemaeciae tae 1 WEED SANOSLONE ANC SHALE, (a saascnc on tesasea aiicleicesiaeeeenes 1 EME PUL ACEOUS, SHALG. cep sine tarsi-s be rhelsapneeebaranacee tea se esther 0 Arenaceous shale containing a few nodules of ironstone... 4 SHON SAO SHOM Cne.asener ie oamenenananmelse qian tne ecsismine slsirespiiste ss 1 Pee ACEOUS SALE wre enieee apiarnmisieeaecnlummces darken -ebeiswe sia ease 2 EA feta ieciiafooscisicwaiaipinielnie < ceva Ree ae aman eactotes secatenkaien ssa 0 Mmelenclays( StiSMATIA)). ch .as0caoiomsinnine mo ciciactd es akiae da chisi Uatae 4 PE UACEOUISESHAlC cepatnaisaeeisieee sonicarakeieannnqasacss ss frase es 5 EMECM AGE OMS! SMALC sam demic ck allem anrceineieiieniseaise Seemeiele,clebialstisialesiee 4 Red argillaceous shale, replaced by sandstone higher up in the cliff (Fucoids and rain-drops in sandstone) ........ SG REE MAT eNAGE OUSISMALE V5 vanaidasac sae ceescecet en tsclaa bias odtzichaee 8 Redeaneillaceous: shale yvs..\qcmestaedweater taeiodehle ee sesideseiodaee 1 Arenaceous shaie (Fucoids, ripple-marks) .........seeesse00. 7 Bit ABEISAMOStOWE. {hues ssccees cenadis se alsaemlantone teeatosereeemees’ 7 PGP ACCOMS SMALE eae a cehetas “eee ase asta ere csisphaemes as ealesespie 1 me — HOOK CMNNUWUOWOOCMOROOSD Lweor) onmD > Hm em DD dO oOONOnw © DBAOOhOOCKNANS Mwmanoohous 119 120 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [ Nov. No. ft. in. 208. Waving alternating sandstones and arenaceous shales 207 AStrOng SANAStOME: Casa. deems eee coos eecsce ada cecee chee eee 21.0 206." Argallaceous sales acesccsuensecee ee scu- n05- nae bee ne eee zt 174. Argillaceous: Shale: 0 cee.cunctemnna ccanasnenaccseccusete neem 2 173. Argillaceous shale containing layers of coal...............00. 0 0 1 6 0 4 0 2 0 8 | 1 0 1 + 6 bol oowncoo SCOoOunNnNVow tes oOoKnowort die bol OF ON WO 172. Coal (Calamites in this) Seam) (Quarry seam)c...0-.-tseresee 0 Carbonaceous shale... 2 Co aliy .ciadusadsnineceniens 3 Winderclaya(Sigmaria cen sscseonscee acess sree cdaisaienatenetiens 3 Argillaceous shale, a layer of ironstone of lin.,5ft.fromtop 8 Red and grey mottled argillaceous shale .......0..........00: 26 PRRCMACE OMS ISM ALC ante nsialoeieeisienemspceries sre mari) feeewiain/sp ise cleehiieas 9 Finely laminated arenaceous shale.........ccssec..-sesserseeses 3 ANIC LOTAS HOI iret oraceeicroedotersyoltaistaitn eistaelal sve cloio ale Serclas ta e oieta eta SeNicva A 0 Arenaceous shales (Fucoids, plants, erect trees) ........... 9 Grey and red mottled arenaceous shale.................:.0000e 13 PRE OAIACCOUS (SIRALE see sticlercicts se afecletesiel tae dio e/a slxproleetecaw ahteateigabeine 3 CAT HOMACEOUS! SMa © ecm tel. welels ae seeloisu alee saltistlemnier seals meine 0 SO allipietier bin. ratchet o cieracioslncralttte sidelscaiis deel sie iselh Sabbah «RA Aeteawsdlelde 0 Wind exelaya (Stiemania)|, 5 -cesrciseasi-s sence see tome cee amiss cele 5 Alternating layers of sandstone and arenaceous shales con- taining a few thin layers of ironstone................2..0008 11 Alternating sandstones and shales (plants) .............00... 12 Argillaceous shale containing ironstone nodules ............ 3 Camuinated) SAM dStOne stoncuncenenvetsn ae snatisterenenecsissiacnes 10 INFEMACEOUS, Shale: (plats) ii «msi casismenet aeeeebiacsees ssseeeeseae 2 ea is OB ade hah earepentielbowtacniaieaaee Calcareo-carbonaceous shale.. 2 | (Cypri ile) Sepals i 0 CERO San cee ere eee Tf thle) one. Wind exe) aye (Stille Tyan) y eye err eS High- OC water | SG : line. Shale 213. Shale 214. shale, No. 214, terminates at the height of eight feet above high-water line, and is replaced by hard laminated sandstone, which overlaps the edge of the shale. The underside of the sandstone, in contact with the subjacent shale No. 213, presents markings of fucoids, which cannot be observed upon the underside of the red shale, showing, that in the interval between the deposition of the red shale and the sandstone unconformably upon its edges, a layer of sea-weeds had been spread over the uncovered portion of the surface of the shale No. 213. The red shales are very irregular in thickness ; thin beds of twelve or fifteen inches sometimes increase to three or four feet in depth 1849. | BROWN ON THE SYDNEY COAL-FIELD. 125 within a space of thirty feet. In some instances a bed of shale of a deep red colour at the outcrop passes gradually through all the shades of red, purple, brown and grey, until, at the foot of the cliff, it can- not be distinguished from common grey shale; and im others, as represented in the cut, a bed three feet thick at the outcrop thins out altogether before it reaches high-water mark. Hig. 2. 1. Grey shale. 2. Red shale. 3. High-water line. Argillaceous ironstone is found in small detached nodules, rarely im continuous layers, in many of the shales, but never in sufficient quantity for working profitably. The total thickness of the sandstone beds is 562 feet; they are of a greyish white colour, sometimes tinged brown or green. The thick beds are generally coarse ; those numbered 272, 282 and 310 contain rounded pebbles of white quartz of all sizes up to one inch in diameter. False stratification is very common in the thick beds ; one of the most remarkable examples is shown in fig. 3, which is a water | SS CEN ETS 9 line. sketch of an outlying mass separated from bed No. 272; its height is 9 feet. Many of the sandstones are micaceous and flaggy ; some (Nos. 42, 292, 293, 294 and 332) so finely laminated and regular in their bedding, that from twenty to thirty distinct layers can be counted in one inch of depth. The bituminous shales are not numerous, their united thickness being only 26 feet ; they are ofa black colour, and all more or less inflammable; those numbered 225 and 227 may be designated im- pure Cannel coals, bemg very compact, possessing a conchoidal frac- ture, and burning for a short time with a bright yellow flame. The remainder are soft and laminated. They are all highly fossiliferous, as will be noticed in the sequel. —a 126 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Nov. 7, The carbonaceous shales, composed of argillaceous mud charged ik ore vegetable matter, occur interstratified with thin layers of coal. The beds of limestone are rare, and with the exception of the two- ich layer, No. 92, very coarse and impure, being charged with car- bon, bitumen, or siliceous matter. The persistence and uniform thickness of all the limestone beds, except those numbered 152 and 154, are very remarkable. The two last are separated at low-water mark by a three-inch layer of shale; at high-water mark they merge into one bed, and at eight feet higher up thin out, as represented in the annexed cut. 151, 153, 155, Shale. aa, High water. 152, 154, 156, Limestone. 5 b, Low water. Only one bed of conglomerate (No. 143) occurs in this section ; it is composed of small quartz and granite pebbles united in a base of brown ferruginous clay. | The sandstones, shales and limestones are traversed by two sets of joints at right angles to the plane of stratification, the course of one set being 8. 80° K., and the other 8S. 5° W., which consequently di- vide the beds vertically into blocks of a rectangular form, as nearly as may be. These joints are of great service in quarrymg the sand- stone beds for building purposes. There are thirty-one seams of coal in this section, whose aggregate thickness is 37 feet ; four only are of sufficient thickness to be worked profitably, viz.— 183 Main Coal oS a sec eaer ee 295. Lloyd’s Cove Seam ......... 360. Cranberry Head Top Seam... 3 8 The relative positions of the several seams may be best understood by referring to the section. The coal is im every instance bituminous ; the quality of that obtained from the four seams above-named is un- exceptionable *. All the coal-seams save one (No. 27), which will shortly be noticed, and indeed almost every layer of carbonaceous shale, lie upon under- : ft. 78. Indian Cove Seam .......... 4 6 5 * About 80,000 tons of coal are raised annually from the Main Seam, of which 30,000 tons are consumed in Nova Scotia, the remainder being chiefly shipped to Newfoundland and the United States. 1849. | BROWN ON THE SYDNEY COAL-FIELD. 127 clays. The upper layers of the underclays immediately in contact with the coal are argillaceous, forming sometimes good fireclays: from six to twelve inches below the coal they contain variable proportions of siliceous matter, being in a few instances scarcely distinguishable from sandstones. Stigmarize are found in all the underclays, in several of the shale roofs of the coal-seams, and in some beds of shale (Nos. 81, 238 and 274) which constitute neither floors nor roofs. In the first case they are very numerous, and of several species, although S. ficoides is the most common. In the second they are not so plentiful, occurring pro- bably only in connexion with the erect trees, of which they are the roots. In the last case they are very rare, and where they are not united to erect trees, most probably have been drifted, carrying with them a portion of their long rootlets, of which there is one very de- cided example in another part of the Sydney coal-field *. It does not appear that the thickest underclays, containing the greatest number of Stigmarize, are overlaid by proportionably thick seams of coal; the reverse is often the fact: for instance, the three lowest seams in our section (Nos. 8, 12 and 15), none of which ex- ceed 1 inch, lie upon underclays 4 ft. 10 m., 5 ft. 4 in. and 3 ft. 4 in. in thickness, respectively, while on the other hand, the seams Nos. 78 and 295, the one 4 ft. 8 in. and the other 5 ft., rest upon under- clays by no means rich in Stigmariz, only 2 ft. 3 in. and 3 ft. 4 in. in thickness. In the two latter cases, probably, the increase of Stig- mariz was interrupted by a subsidence which produced the conditions required for the growth or accumulation of the vegetable mass from which the coal beds were formed. In the former instances, similar conditions having been obtaimed and the growth of the vegetable mass just commenced, a subsidence took place almost immediately, which at once put a stop to the increase of the material required to form coal. If the strata had been suffered to remain in a state of rest for a longer period, the bed of coal No. 8, which is only half an inch, might have attained a thickness equal or superior to any in the section. As before mentioned, the seam of coal No. 27 forms an exception to the general rule; it lies upon a coarse limestone 6 inches thick, which rests upon a hard arenaceous shale, not unlike some of the more sandy underclays ; but it neither crumbles on exposure to the weather, nor does it contain the slightest trace of a Stigmaria or its rootlet. As the limestone contains Cyprides, with the scales and coprolites of fishes, which could only have been deposited in water apparently of a very moderate depth +, we must admit that the thin layers of coal * Whilst examining the cliffs about three years ago near the entrance of the Brasd’or lake, accompanied by Prof. Johnson of Philadelphia, we found a piece of Stigmaria 6 inches long and 3 inches in diameter, with rootlets attached, in the middle of an upright fossil tree. This could only have been drifted: probably those found in the shales numbered 81, 238, &c. were drifted in the same way. 7 The depth of the water could not have exceeded 3 feet, because at that height above the coal we find a soil (underclay) containing the roots (Stigmariz) of trees which once grew on its surface, unless we assume that the strata had been elevated after the deposition of the coal. 128 PROCEEDINGS OF THE GEOLOGICAL Society. [ Nov. 7, constituting this seam were formed from drifted vegetable matter, for we find layers of carbonaceous and argillaceous shale alternating with three layers of coal whose united thickness amounts only to one foot, which is precisely the arrangement likely to obtain from vege- table matter drifted down with mud into an estuary. If then a seam clearly formed from drifted materials assume this arrangement, it is evident that thick beds of pure coal perfectly free from clay, or mud mixed with vegetable matter, could never have been accumulated in the same manner. I have marked all the beds in the section in which plants have been found, but it is very probable that they occur in many other beds and have been overlooked. The shales are the most prolific in plants, especially those which form the roofs of the coal-seams. It is a sin- gular fact, that not even the trace of a fossil plant, nor any organic substance has been found in any of the red shales, although they have been carefully examined for that purpose. Wherever erect trees occur, ferns, Asterophyllites, Sphenophylla, and other delicate leaves, are found in the greatest abundance, from which I infer that they fell from growing trees and shrubs, having been covered up by successive layers of fine mud deposited at frequent intervals over a low, marshy district. In these localities single fronds of ferns are sometimes found covering a slab of shale two feet square, as sharp and distinct in their outline as if they had been gathered only yesterday from a recent fern and spread out with the greatest possible care, not a single leaflet being wanting or even doubled up. Some beds also seem to contain one species of plant only, all others being excluded ; of this we have a striking example in the argillaceous shale No. 60; in the top of this bed, through a depth of three inches, we find Asterophyllites fo- liosa piled up layer above layer from the base of the cliff to the crop of the bed, a distance of 200 feet, clearly proving that these plants grew on the spot. | Plants are not very common in the sandstones; those numbered 272, 282 and 310 are the only sandstones which contain any con- siderable quantity: they consist of fragments of Sigillariz, Lepi- dodendra, and Calamites confusedly mixed together, and evidently drifted from a distance. The impressions of Fucoids without any carbonaceous matter are found in several beds, as specified in the section; in every instance they occur on the undersides of hard arenaceous shales or sandstones in contact with soft shales beneath. They appear to have been long tubular stems, from one-tenth of an inch to one inch in diameter, and are accompanied by detached ovate and globular bodies very much like the capsules and vesicles of recent Algee. Fine ripple-marked sand- stones are generally found very near to the Fucoids, and in two in- stances impressions of rain-drops. The most interesting fossils in our section are the numerous groups of erect trees situated at so many different levels, which I shall now briefly notice, purposing to send to the Society more detailed de- scriptions at a future time, having with that view taken an accurate drawing of almost every individual tree. ) 1849. ] BROWN ON THE SYDNEY COAL-FIELD. 129 a. Starting from the base of the section, the first erect tree is met with in the bed of argillaceous shale No. 51, 222 feet above the mill- stone grit. It is a fluted Sigillaria, 15 inches in diameter and 3 feet high; the base spreads out over the two-inch coal No. 50, but no roots are visible. The interior of the stem is filled with argillaceous shale. See Fig. 5. 6. In the next superior bed of argillaceous underclay, two upright stems of Sigillariz occur only 4 feet apart; one is 18 inches and the other 27 inches in diameter at the top, their height being 4 feet. The stems are fluted and covered with a bark of coal three-fourths of an inch thick. ‘They enlarge considerably as they descend, but no roots are visible. We have here conclusive evidence that a slow and gentle subsidence of the coal-measures was in progress during their NOL a ee = SD hy Be ioe @ Sandstone. “gg [20 accumulation ; the two-inch coal No. 50, at one period the surface on which the first tree grew, having subsided a depth of eight feet, the shallow water was filled up with mud until it reached the surface, on which the two trees in the underclay No. 52 flourished. c. At the height of 147 feet above the last trees, and 21 above the Indian Cove Seam, two large stems of fluted Sigillarize with a coaly bark half an inch thick occur; their length is 5 feet and their dia- meter at the top 24 inches, which increases rapidly as they descend, but no traces of roots can be seen, owing to the soft carbonaceous shale which underlies them having fallen away from beneath. d. About eight feet higher in the section, several erect Calamites, from 4 to § feet in length and 3 to 5 inches in diameter, occur in the micaceous sandstone No. 88. They do not present any traces of roots. e. Erect Calamites, varying from 3 to 8 feet in height, and about 5 inches in diameter, are also met with in the bed of arenaceous shale No. 119, bemg 151 feet above the sandstone No. 88, last men- tioned. No roots are observable. 130 PROCEEDINGS OF THE GEOLOGICAL Society. [ Nov. 7, J. The next erect trees are found 164 feet higher up, in the sand- stone No. 163; here we have two large fluted Sigillariz, 24 inches in diameter and 5 feet in height, standing only eight feet apart: they enlarge rapidly towards their bases, and were probably rooted on the surface of the three-inch coal No. 161, but being very near the high- water line the surf has washed out the soft, argillaceous shale No. 162 from under the stems, and obliterated all traces of roots. We now arrive at a group of strata, the lowest only 28 feet above the preceding, exceedingly rich im upright trees, all standing in view together at six distinct levels within a vertical height of 52 feet. g. The first in the series are three large trunks im the shale No. 175, apparently 30 inches in diameter; they are situated too high up in the cliff to be examined properly ; they all bulge out as they descend, ° coal No. 172. h. Some of the trees in the beds Nos. 183 and 185 have been already described in the Journal of the Society* ; but since that description was written, owing to the constant wasting of the cliffs, several new trees have been exposed, particularly a fine fluted Sigillaria, 18 inches in diameter (seen in fig. 7), with strong roots penetrating down- wards at an angle of 45°, and piercing through the three-inch layer of mixed coal and shale No. 182. z and &. In the arenaceous shale No. 183, several small Sigillarize are found at two distinct levels, some being rooted about the middle of the bed and others near the top. They have Stigmaria roots with rootlets, which, as before mentioned, have already been described in this Journal +. 1. Two small Sigillarize occur in bed No. 185: Stigmaria roots are seen near them, but not in actual contact. m. The shale roof No. 189 of the Main Coal has furnished a great number of upright trees with long spreading roots and rootlets, which it is not necessary to enumerate here, three of the most interesting having been described at length in the Journal, viz. a Lepidoden- dron{ with Stigmaria-like roots, and two curious specimens of Szgzl- laria alternans§. I may observe that Sigillarie appear to be the most common, but I have never seen any larger than 14 inches in diameter. * Vol. ii. p. 393. t+ bid. ¢ Vol. iv. p. 46. § Vol. v. p. 354. 1849. | BROWN ON THE SYDNEY COAL-FIELD. 13] n. A long interval now follows without any erect trees, the next in order being Calamites without roots in the sandstone No. 299, which is 735 feet above the Main Coal No. 188. o. Six feet only above the sandstone last mentioned, a fine erect Sigillaria occurs, based upon the surface of the argillaceous shale No. 302, and extending ten feet upwards into the superincumbent beds. At the height of three feet from the base it is bent over nearly into a horizontal position, the length of the inclined portion 306 being two feet ; it then resumes its upright position, which it main- tains to the top, terminating under the mixed coal and shale No. 306. The diameter at the top is 15 inches, and at one foot from the base 24 inches. It is furrowed throughout the whole length, but leaf- sears are visible only in the upper portion. Two large roots pro- ceed from the base, but no rootlets or resemblance to Stigmaria can be found. Prostrate plants and Stigmarize are found in some of the beds above the shale No. 302, as high up as the top of the sandstone No.310; but above this sandstone not the trace of a plant of any description can be found until we arrive at the argillaceous shale No. 344, 217 feet above the last upright tree. ‘This shale No. 344 is the commence- ment of a series of beds exceedingly rich in both prostrate plants and erect trees, which terminate only with the highest bed in our section at Cranberry Head. I have endeavoured to show the position of all the upright trees at one view in the annexed sketch (Fig. 9), the lower portion being visible in the south-eastern face of the cliff, and the \ es =e upper round the angle of the headland, where the coast-line runs nearly in the direction of the strike of the strata: this will explain why the beds dip so rapidly in one part, and appear nearly horizontal m the other part of the sketch. 132 PROCEEDINGS OF THE GEOLOGICAL society. [Nov. 7, p. Four feet and a half below the surface of the shale No. 344, there are a large Lepidodendron and several Calamites. The Lepidoden- dron, which is the highest tree in the cliff, as shown in the sketch, is 9 feet in height, its diameter at the top being 24, and at the base 36 inches. It is covered with a rough scaly bark of coal 1 inch thick. The trunk is filled up with alternatmg beds of shale and sandstone with several thin layers of ironstone. I could only trace one piece of root 2 feet in length, which externally was marked in the same scaly manner as the stem, beimg filled up with soft shale containing small egg-shaped nodules of ironstone. The Calamites, which do not exceed 2 inches in diameter, have long fibrous roots running nearly perpendicularly downwards. g. I counted ten small upright Calamites and Sigillariee in the next superior bed No. 345, based upon the surface of the shale No. 344, into which their long fibrous roots penetrated from two to three feet downwards. Two of these Sigillariz? are about 8 inches in diame- ter ; they are filled with soft friable shale, and have central columns or piths 14 inch in diameter, composed of pure bright coal arranged in thin horizontal laminee. There is also the stem of a fluted Sigillaria in the same bed of larger size near high-water mark, but only a small portion can yet be seen. r. Twenty-three feet higher up, in the arenaceous shale No. 355, there are three large erect trees whose long Stigmaria roots spread over the flat surface of the Cranberry Head bottom seam. One is a Lepidodendron, the two others are Sigillariz. They are all about 27 ‘inches in diameter, but of different lengths. s. In the same arenaceous shale No. 355, but four feet above the coal, there are two more trees of about the same size as the last, which are apparently Lepidodendra. Long rootlets run in every di- rection from their Stigmaria-like roots. These are the last upright trees in our section, making in all eighteen forests, each on a distinct level and consequently of different ages, within a vertical range of 1600 feet, the first bemg 220 feet above the millstone grit, and the last 40 feet below the highest bed at Cranberry Head. The animal remains, as will be observed by reference to the sec- tion, are chiefly found in the bituminous shales and limestones: in these beds they are very plentiful, but apparently limited to few genera and species. I have only been able to recognize the follow- ing * :—Modiola (2 sp.), Spirorbis, Unio, Microconchus carbona- rius, Cypris (2 sp.), and the scales, teeth, &c. of Holoptychius, Me- galichthys, Paleonjscus, Amblypterus and Gyrolepis, which are very abundant, together with vast numbers of coprolites. The Unio and Microconchus are found alone; the first in the slaty sandstone No. 196, and the latter in the thin limestone No. 92. The Modiole and * J made up separate parcels of the shells and ichthyolites, intending to send one to Mr. Conrad of Philadelphia, and the other to Prof. Agassiz of Cambridge, U.S., but by mistake the shells were sent to Prof. Agassiz and the ichthyolites to Mr. Conrad. This has since been remedied, and I hope soon to be favoured with the remarks of those eminent paleontologists on the Sydney fossils. 1849. | TYLOR ON EOCENE IRON ORE. 133 Cyprides are found with the remains of Holoptychius and Paleonis- cus in the bituminous shales. On comparing our section with that of the Bay of Fundy coal- measures, although the analogy is in many respects very striking, there is this remarkable difference, that, whilst we have the remains of some decidedly salt-water fish and fucoids at various levels in a section embracing a depth of 1860 feet only, “not a trace of any sub- stance of a marine character’? * has been found in the Bay of Fundy section, through a vertical range of 14,570 feet. Although the great mass of evidence afforded by this section is on the side of those geologists who contend that coal beds were formed from trees or plants which grew upon the spot where the coal now exists, yet we certainly have one distinct example of a thin seam (No. 27) formed from drifted materials deposited in very shallow water. In conclusion, I may remark, that many interesting phenomena have necessarily been unnoticed in this brief sketch of the lower por- tion of the productive coal-measures of Sydney, which I shall en- deavour to describe in a future communication. es 3. On the Occurrence of Productive Iron Ore in the Eocene Forma- tions of Hampsuire. By Aurrep Tytor, Ksq., F.G.S. THE presence of large ferruginous Septaria, containmg carbonized wood, principally in small fragments, was noticed in the lower part of the Barton clays, between Barton Cliff and Muddiford, by Mr. Prestwich and myself about two years ago. At that time we did not proceed west of Christchurch; and I was unable to accompany Mr. Prestwich in his more recent visit to the cliffs between Christchurch and Poole, when Mr. Prestwich also noticed the very ferruginous condition of these large tabular Septariat. Having lately had an opportunity of paying a visit to Hengistbury Head, I was much interested in finding that these blocks have been found to contain so large a per-centage of iron as to be available for economic purposes. As productive iron ores have not previously been known to occur in the English tertiaries, I have thought the fact of sufficient interest to be laid before the Geological Society. Mr. Holloway, of Christchurch, who has undertaken these works, informs me that the occurrence of large masses contaiming iron in these cliffs appears to have been discovered in the reign of Charles II., during a survey of the adjoming harbour of Christchurch. The king was recommended to establish iron-works here for the purpose of founding cannon; the ore was to be obtained from the shore, and the charcoal from the neighbourmg New Forest; this scheme, how- ever, was not carried out. Within the last three years Mr. Holloway sent specimens to South Wales for examination. The first impres- sion of the ironmasters was unfavourable; for although, from the * President’s Address, Quart. Journ. Geol. Soe. vol. ii. p. 179. T Quarterly Journal of the Geological Society, vol. v. p. 45. VOL. VI.—PART I. L 134 PROCEEDINGS OF THE GEOLOGICAL society. [Noyv. 21, oxidation of the iron, the Septaria presented externally a highly fer- ruginous crust, yet, when the mass was broken, the grey and earthy fracture more resembled an ordinary compact limestone ; and further, the constant occurrence of fragments of carbonized wood presented an appearance to which they were not accustomed. Mr. Holloway, however, informed me that these blocks were found to contain about thirty per cent. of iron, and that, moreover, vegetable matter was pre- sent in sufficient quantity to facilitate the reduction of the ore. Many hundred tons of Septaria have been shipped to the iron-works in South Wales; and the works have already attained sufficient im- portance to induce the proprietor to lay down more than a mile of tram-way, leading along the base of the cliffs to the ancient, but al- most deserted, haven of Christchurch. The headland of Hengistbury projects immediately west of the Downs bordering the haven, and rises to the height of from forty to fifty feet. From this point the cliffs trend in a north-westerly diree- tion for a mile, gradually decreasing in height. As shown by Mr. Prest- wich, these cliffs consist of the Barton fossiliferous clays, reposmg upon a few feet of fine light-coloured sands. The Septaria occur in three or four bands of such magnitude and regularity that they assume at a short distance the appearance of connected strata. The encroachment of the sea on this coast has gradually under- mined the cliffs, removing the clays and sands, and leaving the shore almost entirely covered with weathered masses of the Septaria. From their size and hardness they have resisted the transporting power of the waves, and extend a considerable distance into the sea, forming the dangerous reef known as Christchurch-ledge. The quantity of such blocks of ore distributed over the beach has been calculated to amount to many thousand tons. This forms the only available source of the material, for although the clays containing these bands of iron- stone stretch some distance inland, yet they could not be profitably worked. The works are of too recent an origin to determine exactly the value of this discovery ; but the circumstance of the ironmasters of South Wales continuing, after the experience of last season, to import this ore, proves that it really possesses considerable commercial value. NOVEMBER 21, 1849. Charles Myer, Esq., was elected a Fellow of the Society. The followmg communications were read :— 1. On a Cutting in the Railway near BUCKINGHAM. By Wix.1aM Stowe, Esq. { Communicated in a letter to the Very Reverend the Dean of Westminster.] I HAVE great pleasure in sending you some particulars relative to the boulders in our railway cutting, to which you directed my attention last autumn. Many of those you saw have been broken up and 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 135 transported as ballast, but some are lying about, and a few remain in situ. I have examined all of them, and find they are composed of that variety of oolite which has been named Buckingham or Forest Marble. Many of them are yellowish externally and bluish within, owing probably to a difference in the degree of the oxidation of the iron which has coloured them. The largest I have measured was about 3 feet by 4, very angular, being but little rounded ; while the smaller ones, 30 inches by 20, whose corners had been modified and whose sides had been smoothed, were covered with scratches and grooves. Section of Railway Cutting at Buckingham. 1. Ochreous gravel, with boulders of forest 3. Dark clay, with Belemnites and rolled marble, and with Grypheece, Belemnites, fragments of chalk. and Ostreze. 4, Experimental shaft. 2. Grey gravel. 5. Grey sand and gravel. The cutting (see fig.) is about fifty feet deep, and the boulders are sprinkled among gravel, sand, and clay, about ten or twelve feet below the surface ; and are not found lower down among the earlier deposits of smaller pebbles, which must have come from all quarters, judging from the variety of rocks they contam. Out of the latter I picked the fragment of fossil bone I sent you a day or two ago—possibly a portion of my old friend the Cetiosaurian, whose tail-bone I sent you some years ago, and which you reported to the Society at the time*. I found one boulder only with perforations ; whether the work of Pholades, or the impression of shells or wood, you will determine from the specimen I send you, taken from one of the largest blocks, and lying nearer the surface than any other. The country around here is very undulating ; scarcely two fields have a similar aspect or inclination, and the hills are capped with gravel, which makes it difficult to trace the stratification. The con- tortions of the gravel beds are very curious, being in some places almost vertical, and in others twisted like the letter S, according as the bed is cut into obliquely or transversely. The gravel has been penetrated to the depth of eighty feet near the pit you saw at Foscot, in search of water, but without success. Looking at the boulders still in setu, I tried to make out from the scratches from what direction they had come, but could not satisfy myself on that point. 2. On the Secondary District of PortuGau which lies on the North of the Tacus. By Danrex SHarps, Esq., F.G.S. General Sketch of Portugal.—So little is known of the geology of Portugal that it may be interesting to give a general sketch of that country before proceeding to the details of the district which is to * Proceedings of the Geological Society, vol. ii. 1833-38, p. 190. ie 136 'y District North of the Tagus. Map of the Seconda ) ee] Esai s « ‘ > Sl = ‘\ \ | [COW "A @ . J A Nee . : : Paks a ¥ ‘ e \ Heke ‘ , r s H ‘ Fed See oS e : ; , . ’ A 2 et . ‘ gitsa . Fe ; F : : pe ae = atl | a a ‘ cae Tee | ‘ > y » ah a ¢ , t « 2 . - . 7 fs ;. ee : : Car “ = ‘ \ ( < >? : | | = . e e = ui f e ‘ Qo, BY 4 7 4 2 . | < oe: Us cx ae Mls ' e ome aa8 . = ; . SS ie ee, 5 : , . 3 >. | | ’ ¢ * : Calan een ee Mi — a 4, \\\ pe ae . iden aN is N e ‘ . ; % : o * A ete ee | e O) ‘ . | 4 - u i Sil 2 , * . > soe s ‘ F : . rl : B . 8 x ° c ’ * 7 & e a ¥ CoN | « } t ‘ mi | \\ 12} 0) UW ; 6 > \: s Soe , a ra , : : » os Ol oT iq f : Reeve % - 4) : r . & | , = Bp . ae - , ; x 1 N Bae eal \ x | of % | Soe NGS ‘A a 9 N ie Dele me Wet ome We ye YL Iewoyy, KK iy — lk - 4 , Lp -_—— be - y ~ = - Yo 2 Y Y cs Zz INS y () /: — Dra —KKCSWVS Ks (ys aL YT) a ory ’ vo. CS = WTS is KS Sas 3 Ds aie AS 9g ay S G ————————————— AS fe} >t No ® % a LY E 5 5° —S SS ee eee ee ties : § =a : ; iS) —<—— i 3 \ YY SS See : . ——— 5 _——————— C. Espichel. 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 137 form the subject of the following paper: this has been drawn up _from my own observations and from a variety of sources mentioned in their places. Commencing at the north with the Spanish province of Gallicia, which has been described and roughly mapped by Schulz*, two- thirds of the surface of Gallicia are formed of granite, gneiss, mica- schist, and other crystalline rocks, which cover nearly all the western and middle portions of the province: the eastern side is principally formed of slate, grauwacke, &c., classed by Schulz as Transition Rocks, among which we may expect future observers to find the Silurian and Devonian formations. The strike of the slates varies, but its mean appears to be about N.N.W. There are some small patches of secondary red sandstones and marls scattered over the province, of which the age has not been ascertained ; here and there a small tertiary deposit occurs; and the bottoms of many of the valleys are filled up with thick deposits of gravel. Passing southward into Portugal, we find the same formations continued in nearly the same direction: the greater part of the pro- vince of Minho and the western side of Traz os Montes consist princi- pally of crystalline rocks; but the rest of Traz os Montes is mostly formed of slates, which are continuous with the same rocks lying on the east of Gallicia. With occasional interruptions of slates and other rocks, some of which may perhaps be of more modern date, the crystalline rocks are continued towards the S. or S.S.E., in a band forty or fifty miles wide, through the whole extent of Portugal, from the province of Minho to the banks of the Guadiana, including in their range the great mountainous district of the Serra de Estrella: in this course the granites, &c. gradually slope away from the Atlantic and approach the Spanish frontier, while the slates on their eastern flank slope down into Spain. The wild country occupied by the crystalline rocks offers few attractions to travellers, and I can meet with no information about it beyond a few notices in the Appendix to Link’s Travels}. The highly cultivated district of the Upper Douro, which supplies all the fine port-wines, has been described by Dr. Rebello de Carvalhot ; it is formed of slate-rocks, supposed by that author to belong to the Silurian system, which strike W.N.W. and are nearly surrounded by granitic mountains. On the western side of Spanish Estremadura we find the con- tinuation of the crystalline and slaty rocks, which strike about N.W. and are partially concealed by the tertiary deposits of the basin of the Upper Guadiana§. The great granitic band above-mentioned is flanked on its western * Descripcion Geognostica del Reino de Galicia por Don Guilhermo Schulz. Madrid 1835. tT Geologische und mineralogische Bemerkungen auf einer Reise durch das stidwestliche Europa, besonders Portugal, von F. Link, 1861. ¢ Consideracoes Geraes sobre a Constituicao Geologica do Alto Douro, por Jozé Pinto Rebello de Carvalho. Porto, 1848. § Anexcellent account and map of this district have been published ee Le Play, Annales des Mines, 3rd series, vol. vi. 1834. 138 PROCEEDINGS OF THE GEOLOGICAL society. [ Noy. 21, side by various slaty and schistose rocks. I have already described to this Society a portion of these*, which beginning on the north at Esposende, line the coast as far as the Vouga, with the exception of a range of crystallime rocks, of which the granite of Oporto is the central axis. Near Vallongo a bed of anthracite coal underlies Lower Silurian slates, which form part of this series. From the mouth of the Vouga the schists run 8.E., keeping on the north side of that river: they then turn southward, and after running along the Serra de Busaco, pass about four miles to the east of Coimbra, and continue along the little river Deuca, and then down the lower part of the Zezere to the Tagus near Abrantes. The district which lies between the schists just mentioned and the Atlantic, bounded on the south by the agus, and covered for the most part with secondary deposits, forms the subject of this memoir; but before entering on its description, I will carry this short summary through the South of Portugal. Proceeding southward from Abrantes, we descend into the great tertiary basin, through which the Tagus and the Sado reach the sea ; this tertiary area covers between 2000 and 3000 square miles, and is ouly interrupted by the ridge of secondary rocks extending from St. Ubes to Cape Espichel. Near the sea the tertiary deposits are all of marine origin, and the most important part of the series, called in my former paper} the dlmada beds, has been shown by Mr. James Smitht to be of the miocene period. The Almada beds extend up the Tagus to Verdelha; about fifteen miles higher up the river, the hills on the north bank of the Tagus, rising to a height of perhaps 200 feet, consist of brown marl overlaid by soft rubbly limestone, containing Lymnea longiscata, Sow., a shell common to the fresh- water beds of the eocene and miocene periods. I traced these beds of lacustrine limestone from Cartaxo by Santarem towards Golegao : they are not found near the mouth of the Tagus, and are perhaps the lacustrine equivalents of the marine Almada beds. A little above Villa Franca I met with a bed of marl about fifty feet above the present level of the Tagus, containing the common Lutraria compressa, and in the marshy flat near Villa Nova da Rainha the same shell and a small variety of Cardiuwm edule, both of which now live in abundance in the estuary of the Tagus near Lisbon; so that it is evident that this part of the country has been upheaved at least fifty feet within a comparatively recent period. The upper part of the tertiary basin forms a great marshy district, which will probably prove to consist of lacustrine or fluviatile deposits of very modern date. On the north side of Lisbon a great area is covered with basalt, which separates the secondary from the tertiary formations. The * Quarterly Journal of the Geological Society, vol. v. p. 142. + On the Geology of the Neighbourhood of Lisbon. Trans. of Geol. Soc. 2nd series, vol. vi. p. 107. t On the Age of the Tertiary Beds of the Tagus. Quart. Journ. Geol. Soc. vol. ili. p. 410. 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 139 lime of demarcation between these two great systems is as strongly marked in Portugal as it is in our own country. On the south of the tertiary basin, the centre of the province of Alemtejo is covered by secondary beds, probably older than those to be described on the north of the Tagus, but the true age of which has not yet been determined: these are bounded on the south by the lofty chain of hills, called the Serra de Monchique and Serra de Caldeirao, which separate Alemtejo from Algarve, and which consist of schists and slates, with the exception of granite at the Cabeca de Monchique. Dr. Welwitsch has informed me that schists also occur along the coast of Alemtejo from Cape Serdao to Sines, and that the Cape of Sines is formed of syenite. On the south of the chain of Monchique and Caldeirao lies the little kingdom of Algarve, which has been carefully surveyed by M. Bonnet, from whom we may hope to receive a geological descrip- tion of it; that gentleman told me that a band of secondary rocks lies on the south flank of the schistose chain, which is again overlaid along the south coast by tertiary deposits. Considerable outbursts of trap near Cape St. Vincent are mentioned by Link. Thus it appears that there are two districts of secondary and ter- tiary rocks in Portugal ; the southern of which consists of the narrow strip of Algarve; the other commencing on the north side of the Algarve mountains extends up to the Vouga, forming a narrow triangle of which the base at the south is about forty miles long, and the height from north to south is about 200 miles: the secondary rocks of this latter area are divided into two parts by the tertiary basin of the Tagus and Sado. It is the northern division of this secondary district, viz. that which lies to the north of the Tagus (see fig. 1), which I now propose to describe. Throughout this paper I shall commence with the upper formations, and describe them in descending order under the following heads :— Hippurite lmestone, equivalent to our chalk. Subcretaceous series. Jurassic series. Sandstones of undetermined age. With the exception of certain deposits of sandstone last mentioned, no secondary rocks older than the lias have been seen in Portugal north of the Tagus; nor have any traces of the carboniferous series been met with in any part of Portugal. Hippurite Limestone ; equivalent to the Chalk of the North of Lurope. The description of this formation will be found in my paper on the ‘Geology of the Neighbourhood of Lisbon,’ p. 115; and as this rock does not occur to the north of the district described in that memoir, I have little to add to the account there given of it. The hippurite limestone is the uppermost of the secondary de- posits, and near Lisbon is usually overlaid by basalt, which bursts out in great quantities in that neighbourhood in the interval between 140 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [| Nov. 21, the deposition of the secondary and tertiary formations, and which covers a large tract round Lisbon. There are three separate patches of the hippurite limestone; one of these is on the west side of Lisbon and extends a few miles down the river to Belem; this mass of limestone has been thrown into a saddle, of which ‘he axis runs down the valley of Alcantara, just outside the city, with a direction of about N. 30° W., on each side of which the beds dip away from the axis at angles of 5° to 10°; the limestone of many of the beds is shattered to a remarkable degree, and intersected by fissures which run in a direction parallel in the main to the line of the valley, but are waved and irregular. Several of these are sometimes seen in the thickness of a foot, while others are two or three feet apart. There are also three limes on which the beds have been unconformably deposited upon those below, and the fissures just mentioned commence above the lowest of these and end at the upper one; yet notwithstanding their unconformable depo- sition, the same species of shells are found through all the beds. Therefore the disturbing forces must have acted during the depo- sition of the formation. The quarries on both sides of this valley furnish an inexhaustible supply of organic remains. Another range of hippurite limestone extends from the shore of Cascaes Bay towards the north-east nearly to Loures, and also spreads out along the coast eastward beyond Passo d’Arcos: many of the hills of limestone are covered with detached masses of basalt, which is itself frequently capped by tertiary beds: and between Oeiras and Fort St. Julian the limestone is directly covered by a large patch of the Almada tertiary limestone full of its usual fossils. The remaining line of hippurite limestone reaches from Montelavar and Pero Pinheiro to the hills immediately south of Bucellas, in which a good section is exposed in the ravine leading from Tojal towards Bucellas. At Pero Pinheiro the limestone has been largely quarried and organic remains are plentiful. To the south-west of this place a little correction is required in my map published in our ‘Transactions,’ vol. vi. pl. 14: the limestone instead of stopping at the farm of Quinta Granzea should be continued in a thin zone round. the southern edge of the basalt, till it meets the sandstone on the north of Algeirao. | The hippurite limestone is laid down in the map just referred to between Villa Franca and Trancozo, and again as extending from Villa Franca to the north-west beyond Alenquer: this is an error in each case, into which I was led by. thé great resemblance in the mineral character of these limestones to that of the hippurite lime- stone, not having then collected many organic remains: subsequent examination has shown that the limestones in question belong to the lower part of the subcretaceous ee under which head they will be described in due course. It appears therefore that the hipatinite limestone is not to be seen to the north of Bucellas ; nor have I seen it 7m s¢¢w anywhere beyond the neighbourhood of Lisbon ; but it is probable that it occurs near 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 141 Seville, as the church of the Hospital de Sangre in that city is built of a rose-coloured marble closely resembling that of Pero Pinheiro, and full of the same species of Caprinula and Spherulites as are found in the hippurite limestone near Lisbon. I have only to add a list of the organic remains found in this for- mation, by which it will be seen that all the species known elsewhere belong to the chalk or greensand. Coupling with this the fact that the hippurite limestone is the uppermost bed of the secondary series in Portugal, we cannot hesitate to class it as the equivalent of the chalk of northern Europe. It is remarkable that fifty-five per cent. of the species found in this formation are new, only forty-five per cent. being known to the north of the Pyrenees. It is also worthy of notice that no cephalopods nor brachiopods have been found in the hippurite limestone. I shall return to this subject before concluding. From the close proximity to Lisbon of the quarries in the valley of Alcantara, I had far more opportunities of collecting fossils from this than from any of the lower formations: the following table is therefore more nearly com- plete than any of the succeeding lists. Organic Remains of the Hippurite Limestone near Lisbon. Astreea? (one species). Echinus Olisiponensis, n. s. Brissus scutiger, n. s. Arca Moutoniana, D’ Orb. Olisiponensis, n. s. Passyana, D’ Ord. Avicula Olisiponensis, n. s. Caprinula brevis, n. s. Boissyi, D’ Ord. —— d’Orbignii, n. s. Doublieri, D’ Ord. sp. Cardium corrugatum, n. s. Olisiponense, u. s. Cyprina cordata, n. s. globosa, n. s. Diceras Favri, n. s. Exogyra Olisiponensis, n. s. Exogyra plicata, Lam. Isocardia cretacea?, Goldf. Ostrzea globosa, Sow. Pecten inconstans, n. s. striatocostatus, Goldf. Perna? fragilis, n. s. Pholadomya Ligeriensis, D’ Ord. Nerinzea Eschwegii, n. s. nobilis, Goldf. Olisiponensis, n. s. Tylostoma globosum, n. s. ovatum, N. Ss. Spherulites angeiodes, Lam. —— cylindracea, Des Moulins. Ponsiana, D’ Archiac. Sauvagesii, D’Oré, ventricosa, Lam. Lowest beds of the formation at Papel on the road from Lisbon to Cintra. Anomia convexa, Sow. Artemis elegantula, n. s. Arca Moutoniana, D’ Ord. Lowest beds of the formation near Bucellas. Cardium corrugatum, n. s. Subcretaceous series, including the Red Sandstone Formation and the Espichel Limestone of my paper of 1839. The hippurite limestone rests, with a deceptive appearance of con- formity, upon ferruginous sands belonging to different portions of a very extensive series of beds, which are here considered together, 142 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. | Nov. 21, since it has not been found practicable to subdivide them into separate formations, notwithstanding their great thickness and com- plexity. The series consist of various alternations of sands or sand- stones with limestone, and appears to represent, on a far larger scale of development, the beds which in England lie between the chalk and the oolites. Reaching from the Bay of Cascaes to the mouth of the Vouga, these subcretaceous rocks line the coast of Portugal for about 150 miles, except at the sea-board extremity of the Cintra Hills and the point of Cape Mondego. The breadth of country covered by them varies from twenty to forty miles. Throughout this district the continuity of the subcretaceous beds is occasionally interrupted ; being broken through by the granite of Cintra and beds raised up in contact with that rock, by several great chains of limestone belonging to the oolitic series, upon which the subcretaceous beds rest uncon- formably, and by several local outbursts of trap. Nevertheless the suberetaceous rocks probably cover more than nine-tenths of the secondary district on the north of the Tagus. The difficulty of subdividing this great series arises from the close resemblance of the different beds of limestone, and from the faint traces of bedding in the loose, incoherent, ferruginous sands. Where there are no beds of limestone, whole districts consist of great masses of sand and gravel, in which it is difficult to find the direction of the dip or to trace any clear order of superposition; the whole almost resembling a mass of diluvial gravel. Organic remains are very rare in the sandstones, but they are abundant in most of the beds of limestone belonging to this series, and they offer differences by means of which we obtain some idea of the relative ages of the beds seen in distant parts of the district : but it will require a farther examimation of the country before all the difficulties connected with this formation can be solved. The beds of limestone are most prevalent between fifteen and forty miles north and west of Lisbon, and become more and more rare as we proceed northward; this may be partly due to differences in the age of the beds, but is probably also owing to irregularity in the deposition of the limestones, which seem to be local deposits intercalated in a great arenaceous formation; as the Kentish-rag limestone, in England, is a most variable and uncertain companion to sandstones of about the same age as those under consideration. In travelling southward from the north of Portugal, the subcreta- ceous beds are first seen two or three miles to the south of the Vouga: their northern boundary runs from N.W. to 8.E., nearly parallel to the course of that river: they consist of coarse incoherent sandstones and sands with little trace of bedding, and closely resemble the superficial gravel with which that part of the country is covered. The low plains round Aveiro are so completely covered with gravel that the northern edge of the sands is concealed near that city, but at Serddo they are seen dipping S.E. 5°, and resting unconformably on an older formation of red sandstone that dips at the line of junction 8. 30°, and which is described in the sequel. 1849.| SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 143 Some insignificant and nearly horizontal beds of limestone are seen interstratified with the sands near Mamarosa, about three leagues from Aveiro on the road to Coimbra; in these were found Pecten quinquecostatus, Sow. Diadema Lusitanicum, n. s. Exogyra conica, Sow. The first two, being common in the north of Europe in the upper green- sand, show us that the limestones of Mamarosa belong to the upper- most part of the subcretaceous series. Below the limestones there is a repetition of coarse ferrugimous sands and incoherent sandstones, all of which might be easily confounded with the modern gravel but for the guide afforded by the fossiliferous beds of limestone. The position of the beds along this part of the country will be seen in section No. | (fig. 2), drawn from Aveiro to Coimbra. At Vendas Novas, four leagues N.W. of Coimbra on the Aveiro road, and also at Mealhada, three leagues north of Coimbra on the Oporto road, beds of a grey argillaceous limestone, nearly horizontal, are seen below the sands of the subcretaceous series ; these limestones contain fossils of the age of the lias which will be enumerated in their place ; the limestones are of no great breadth, and on passing them we find again the same slightly ferruginous sands, occasionally con- taining some insignificant beds of limestone, which continue to the village of Sarjento-mér, about six miles north of Coimbra, where several thin beds of limestone, very full of shells, crop out with a slight dip N.W.., resting on a loose sandstone. The species found at this spot are the following : — Exogyra conica, Sow. Nerinza Conimbrica, n. s. Pecten eequicostatus, Lam. Tylostoma ovatum, n. s. Phicatula pectenoides, Sow. Natica bulimoides, Leymerie sp. Nerina cylindrica, Voltz. globosum, n. s. punctatum, n. s, The first four species in this list are well-known shells of the green- sand, and the first-named two species of Tylostoma are common in all the upper portions of the subcretaceous beds of Portugal, and are also found in the hippurite limestone at Lisbon; so that we may safely refer this limestone to the upper portion of the subcretaceous series, notwithstanding the presence of the Nerinea cylindrica, which in Germany is found in the Kimmeridge clay. This bed of limestone continues towards the S.W., and was seen again in that direction at San Fagundo, where I collected Tylostoma ovatum, n. s., Tylostoma Torrubiz, n. s. ; globosum, n. s., from thence it is probably continued southward to Condeixa, which stands on a horizontal bed of similar limestone, containing Tylostoma ovatum, nN. s., Tylostoma Torrubia, n. s. ; at both these two places the shells of the genus Tylostoma are ex- cessively abundant. Both at Condeixa and Sarjento-mér the bed of limestone just men- PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [| Noy. 2], 144 "SYSTYOS SNOODVOTIAT ‘OUOJSPUBS POY “SqSTUOS 8 & S . * . S Re a Co) .o = Dd =| [=| > se PA htt 2 S8& 8 i So's ~ pm Ss S a “ony a base *QUOTFO CAT S hy ‘soUOUMLUTY oIsstIT A BS eae oisstany? ‘NUOPSOUUT] PUB PULS JO SUOTVULITY ‘spuus snoULsnAtoyy ym ‘ouojwoury fg Bes ivf) ta ig 2) I J =) a 4 ae 5 5 E ae a a 5 a a ‘S o be =a ) is oe G9 br . . 3 E i 2 e" 3 “AN (*So[tUl QZ) ‘“MLgurog 07 nolohnyy ap aqguod ay) Wouy *% “ON WOLPAY—"e “OL ‘QUOJOUNIT —*STISSOF puns ‘om ‘soqroUy ‘OUOJSOUNTT puLv spuBs Jo -Uo9Id YIM DISSRIT YJIM ‘spuus DIMI DANSOVST ‘spurs oIssuny? suolRutoypy ‘oo sou] ‘SPURS SHOULSNALOST ‘OuOJSsoWUIT SnNoULdnAIoy, YI ‘ouojsovuryY sSnourdnoy "TOAwLD SNOOOVOT [AL ‘OUOISPULS POY il B10 “A'S'S A ee ee “BCG ULTO() Lou -o7ua lieg ‘SBAON SVPUO A *BSOIBUNG TAL ‘OMOAV “AX NUN (‘solu Ce) “MuQuiog Of OMaapT WOK, “| “OAT WOLQIAG—"G “SIT 145 SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 1849.] *IeULOU,L, SC SiG | "UOISIAIP LOMO[—UWOTJVUIIOZ SNODDRII.IOGQNS a ee oe ae) QD oO : . | nD oR 2 YW os =| 72) Seo wo = . “— 3 = 3 o o o = is Cus S 5 3 =) ° f<| oO 2 ie} a oOo Sp “4 Lio} » < SJ + i ra - = & 2) nD ty n n = n 2 mos ao} o 3 o as) aS oO ial a mn wn a g | S yD Ss : S Ge tee te ee 5 g <== SSS So SR ——— Se sss me : —= ~ SSS, SS SRS OSS aE CE EE SSS SS oe << on eases oe, = SSS SS EEE + oo ae Ysie yal ‘ronbusly “*CJOUILD ‘sopisnjoy ‘epniy *S}IOT ‘OZODULLY, *svppoong a’ NUN (‘sop QZ) ‘anbuaypy pun snpjoong ybnowyy, *G ‘OAT U017z009—"g SI *9U0}SpUvSs *QUO0JSOULTT SNOULSNLIO 7 oIssvane? (-soytu QS) (:: Ferruginous sandstone Sands, with some limestone beds. “TIONG “LDULOY J, O72 DiMA UWObsT ‘spues snoulsni07 "EON U01}999—"P “SLT Limestone, with Exogyra plicata. \ Basalt. Limestone. “eLI1o'] Tertiary conglomerate. Ss. ae nae =< $ x & & Pa ey £2 Aet i) “ASS 146 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Noy. 21, tioned rests on red marl and ferrugimous sands, also belonging appa- rently to the subcretaceous series, and resting unconformably on the jurassic limestone of Coimbra described farther on. At Condeixa the subcretaceous beds are overlaid by an extensive deposit of travertine, which is spread out in irregular patches over the low country for many miles round that town ; in many places the travertine is twenty or thirty feet thick ; it consists of a variable mixture of sand and lime brought down by the streams of water which traverse the beds of sandstone and limestone of the neighbourmg hills and break out in powerful springs at their base, the sand beimg rolled down by the streams and then united by a compact cement of lime which had been held in solution in the water. The travertine appears to have been forming from a remote period down to the present time; in the neighbourhood of the springs it may be seen newly formed and quite soft; below this it forms a solid rock, and the lower and older beds are so hard that they are extensively quarried for millstones, which have a great re- putation all over Portugal: some of the lower beds contain many stems and impressions of the leaves of dicotyledonous plants. From Coimbra to the sea the Mondego runs through a broad marshy valley with many lateral branches of considerable extent ; these, like the main valley, are on the line of great faults: hence the sections which may be observed in the hills enclosing the river have a want of regular connection. I followed the north bank along the line of section No. 2 (fig. 3). The jurassic limestone of Coimbra is overlaid unconformably, as has been already mentioned, by red sands and marls with some subor- dinate beds of limestone, in one of which at San Fagundo three species of Tylostoma are abundant; this is covered to the westward by sands and loose sandstone, containing occasional beds of limestone, with a very slight dip westward : the only shell observed in these beds was Exogyra conica, which is very common in most of the lime- stones. Similar beds continue to Montemor-velho, where they are interrupted by a ridge of limestone hills rmmning from the bank of the Mondego to the N.N .E., on which the suberetaceous beds rest unconformably with a dip of 3° W. The limestone of Montemor- velho is of the age of the lias or of the lower part of the oolitic series. On the west side of the Montemor ridge is a flat marsh, on a lme of fault, beyond which we again come to ‘the subcretaceous sandstones dipping N.W. 30°, and containing a bed of limestone about 100 feet thick with abundance of shells of the genus Tylostoma ; this is pro- bably the same bed as that seen near Coimbra at Condetxa and San Fagundo. Beyond the Ponte de Mayorca, which crosses a broad marsh following the line of an important fault, lies a thick formation of limestone near the village of Mayorca ; this I failed to examine owing to the night coming on, but M. Bonen who had resided for some months in this part of the country, informed me that it is the continuation of the limestone of Cape Mondego, which I shall shortly show to belong to the middle of the oolitic period. The limestone of Mayorea is overlaid by a thick deposit of ferru- 1849.| SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 147 ginous sand and coarse sandstone striking nearly E. and W. which continues to Buarcos: this sandstone is overlaid by a formation of hard whitish argillaceous limestone between 100 and 200 feet thick which dips 8.8S.W. 15°, and forms the northern bank of the Mondego for about six miles, extending from the fort at the entrance of the river, and passing under the little town of Figueira to the first great bend of the river: during this course, the limestone rises from the water’s edge to the top of the hills which bound the river. If con- tinued in the same direction to the eastward, the Figueira limestone would cross the Mondego and extend towards Soure, through a part of the country which I did not examine. The Figueira limestone is rich in fossils, but it is so hard that they are not easily extracted ; the following were found between the town and the fort :— Exogyra conica, Sow. Echinopsis subuculus, n. s. Gryphza columba, Lam., very abundant. Cidaris leviuscula, Agassiz. Pecten Dutemplei, D’ Ord. Toxaster Couloni?, Agassiz. Turritella Vibrayana, D’ Ord. Brissus subdepressus, n. s. Turbo Munda, n. s. Scalaria, fragments. Tylostoma Torrubie, n. s. Turritella, fragments. Nerinza Munde, n. s. These species indicate that we are still im the upper portion of the subcretaceous series. The most abundant and characteristic shell in this locality is the Gryphea columba, which I have not met with elsewhere in Portugal. In mineral character and in its greater thick- ness and compactness, the Figueira limestone differs from all the beds of subcretaceous limestone yet described, which, added to some differ- ence in organic remains, makes it probable that it is a different bed. There is a good descending section along the coast from Figueira to Cape Mondego in the following order : — Figueira limestone, dip 8.8.W. 15°. Calcareous sandstone, dip 8.S.W. 15° (a few feet only). Soft light brown sandstone, dip for about one mile S.S.W. 152, then changing gradually toS.S.W. 10°; this sandstone passes into a hard, dark, ferruginous, calcareous conglomerate, and then into a hard red grit, dip 8.S.W. 10°, on which stands the village of Buarcos. West of Buarcos are various red sandstones of softer character, with occasional alternations of red marl, dipping first E.S.E. 15°, and then S.E. 40°; these rest on a series of beds of sandstone alternating with limestone, the organic remains of which belong to the upper part of the oolitic series; below this is the coal series of Cape Mondego resting on limestones indicative of the middle portion of the oolites, which will be described in detail farther on. There is a gradual passage from the Figueira limestone down to the sandstone of Buarcos; so also there is a passage from the sand- stone west of Buarcos down to the base of the jurassic series of Cape Mondego: and if this section alone were considered, it might be thought that we had here a passage from the subcretaceous to the jurassic formation ; but this cannot be the case, for as we proceed southward we shall meet with subcretaceous beds of an older date “RET 148 PROCEEDINGS OF THE GEOLOGICAL society. [Nov. 21, than those of Figueira and Buarcos, and with jurassic limestones more modern than those of Cape Mondego. We must therefore presume that there is a complete break in the series at the line where the dip changes on the west of Buarcos, although the aspect of the country does not indicate any great change, and the sandstones on the two sides of the line of fault are not of very different character ; and that this is a case, of which we shall meet other examples, where the resem- blance of sandstones and sands of different ages, but in close contact, makes it difficult to draw the exact line between two formations, the difference of which is sufficiently marked at a moderate distance from the line of junction. If we review the whole extent of the subcretaceous beds on the north of the Mondego, we see that (except near Figueira) they usu- ally strike from N.N.E. to 8.S.W. with a very slight dip to the W.N.W.: guided by this clue and by the light afforded by the or- ganic remains, we may class the beds roughly in the following de- scending order :— Sand: in all the N.W. part of the district. Sand and loose sandstone with alternations of thin beds of limestone, in which the commonest fossil is the Exogyra conica. Sands and sandstone. Limestone of Sarjento-mor, San Fagundo, Condeixa, and the hill west of Montemor, abounding with various species of T'ylostoma, &e. Red sands and red marls, round the Coimbra limestone. The above form a connected series ; below these we must place the following, leaving it doubtful whether there is any gap in this part of the series :— Limestone of Figueira, with Gryphea columba and numerous other fossils. Sandstones and grits between Figueira and Buarcos. These include all the subcretaceous beds seen on the north of the Mondego. Near Coimbra the various formations cross the Mondego with only a slight derangement of their course ; and I have already described the continuation of the subcretaceous beds to Condeixa: to the west of the latter town they are separated from the great western expanse of the formation by a chain of jurassic limestone which reaches con- tinuously for above sixty miles from near the Mondego to Monte Junto, about forty miles north of Lisbon, which will be described in its place. I did not follow the beds to the eastward of this cham below Condeixa, nor did I examine the hills along the south bank of the Mondego. , From the mouth of the Mondego opposite Figueira to Leiria, the road crosses a great extent of ferruginous sands and loose sandstones with very few beds of limestone, the whole covered by a considerable deposit of coarse gravel, which is both coarser and more abundant near the sea and diminishes as we proceed inland. This is a dreary district principally covered by barren heaths or pme woods. The beds are nearly horizontal with occasional changes of dip. This ap- 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 149 pears to be a repetition of the country lying to the south-west of Aveiro, and probably belongs like that to the uppermost part of the subcretaceous group. Between Leiria and Redinha, the road from Lisbon to Oporto crosses similar beds of ferruginous sand. Thus we have here lost the fossiliferous limestones seen on the north bank of the Mondego, and seem to begin again at the top of the subcretaceous series. Leiria stands on a mass of trap which has thrown up and altered the beds in contact with it. On the east side of the town a bed of limestone, dipping E. 45°, rests on the trap. Eastward of Leiria is a continuation of the ferruginous sands and gravels for about four miles, where they overlie a limestone nearly 100 feet thick, dippmg N.W. 5°, and containmg Lwrogyra plicata, Lam., Ostrea, &c. Eastward of this for several miles the country consists of hills of coarse sand, gravel, and sandstone, with some few beds of limestone. ‘Towards Aldea da Cruz and Ourem the -limestones are rather more important, dipping westward 2° or 3°. The old town of Ourem stands on a conical hill of sand and gravel capped by a bed of compact white limestone nearly horizontal, and contaiming Exogyra plicata, Lam. Cidaris. Mytilus ornatus, D’ Orb. The gravel below the limestone exactly resembles the modern su- perficial drift which covers the low country near the sea, but for- tunately the overlying limestone with its cretaceous fossils preserves us from error on this head, and enables us to estimate the age of other similar gravel beds in the district. For five or six miles farther east are beds of ferrugimous sand, similar to those so often described, containing some insignificant beds of limestone, and dipping W. 3°. The preceding series rests on the jurassic rocks of the great lime- stone chain already mentioned, which here dip E.S.E. 10°, consisting of a compact white limestone of great thickness, resting on soft ferru- ginous sandstones alternating with limestone, which latter beds are but slightly exposed on the western flank of the chain. The section No. 3 (fig. 4) explains the position of the beds along the line just described. From the mouth of the Mondego to the boundary of the forma- tion beyond Ourem, we appear to have a gradually descending series of beds; but from their very slight inclination they may be of no great total thickness, notwithstanding their covermg a considerable extent of country: the whole appear to belong to the upper part of the subcretaceous series. The Hzogyra plicata here takes the place of the Ezogyra conica, which is so abundant north of the Mondego : as we proceed southward we lose the latter species, and the LZ. plicata becomes more abundant, and is throughout a large district round Lisbon the most characteristic shell of the cretaceous and upper half of the subcretaceous series. To the south of Leiria the principal rock is still a coarse ferrug!- nous sand, but the alternations of limestone are more frequent ; all the beds are much disturbed, and there are frequent changes of dip, VOL. VI.—PART I. M 150 PROCEEDINGS OF THE GEOLOGICAL society. [ Nov. 21, caused apparently by the eruption of igneous rocks to which the trap of Leiria belongs: one mile south of the town are some beds of grey argillaceous limestone, dipping E.S.H. 30°; a little farther south the road crosses several beds of limestone alternating with sandstone, dip S.S.E. 45°. Some of the limestones are full of a small oyster, others are almost entirely composed of the shells of Perna rugosa, Goldfuss, a shell found in Germany among the oolites: perhaps a jurassic bed of limestone is here thrown up to the surface, among the sand- stones of the subcretaceous series. Near Batalha we escape from the disturbing influence of the trap, and the heds resume their more usual dip of N.N.W. 10°; among some other small shells, I found be- tween Leiria and Batalha Corbula carinata’, D’Orbigny, a greensand species. Some considerable beds of limestone pass through Aljubarota, running 8.8.W. with a dip varying between S.W. 10° and N.E. 5°: they contain Perna lanceolata, Geinitz. Trigonia, a fragment. Lithodomus przlongus?, D’ Ord. Corals, various. Below this to the eastward are the usual sands, with a thick bed of limestone near Candieiros, containing Terebratula Moutoniana, D’ Ord. These fossils show that the beds all belong to the subcretaceous series *. From Carvalhos near Batalha to the southern extremity of Monte Junto, the subcretaceous beds rest unconformably and at a low angle on the base of the high ridge of hills of jurassic limestone already alluded to, in which the beds, dipping to the east or west in different parts of their courses, are frequently highly inclined and much dis- turbed. The country between the jurassic limestone beds just mentioned and the sea consists for the most part of sand and sandstone, and for many miles round Caldas da Rainha there is scarcely a trace of lime- stone: the sand beds in that neighbourhood probably belong to the upper part of the series, which is everywhere principally composed of ferruginous sands+. The subcretaceous beds continue to cover the country to the south- ward, but I am not able to give a connected account of them in that direction, and must pass on to the country covered by them to the north-west of Lisbon and north of Cintra. The uppermost beds of the subcretaceous series near Lisbon are the ferruginous sands which come out from below the hippurite limestone along a line reaching from the coast of the Bay of Cascaes nearly to Loures, usually with a considerable dip to the 8.W.; these * Some additional specimens since received make it probable that the limestones of Leiria and Aljubarota belong to the lowest part of the subcretaceous series, and may be identical with the limestones seen between Sobral and Torres Vedras and at Alenquer. { A bed of asphalte has been found in this part of the series to the west of Aleabaea, but I can give no details respecting it, as I did not visit the spot. 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 151 contain some beds of red and variegated marls, and the thin bed of lignite mentioned in my former paper (p. 119). Below these we find a great thickness of limestones, alternating first with sandstone and lower downwith shale, very rich in fossils; these beds encircle the Cintra hills, near which they are thrown up to a high angle: details of their position will be found in the sections pl. 15 of the sixth volume of our ‘Transactions.’ The lower part of this series was separated in my former paper under the name of the “ Hspichel Limestone,” but a farther examination of the country and a careful scrutiny of large collec- tions of fossils from both parts of the series have convinced me that the whole belong to one formation, and that the separation of the Espichel Limestone must be given up. I have also to correct an error in mapping the district on the north side of the Cintra hills (vol. vi. pl. 14 and 15, sections 2 and 5), where the San Pedro limestone and slate-clay are marked as if con- tinued round the north side of the chain. These two formations are well exposed on the east side of the Cintra hills, but they stop a little to the north of the village of San Pedro, and from Cintra to the coast the subcretaceous limestones rest immediately on the granite. The limestones in contact with the granite are all altered into white semi- crystalline marble, and this uniformity of their mineral character led me to refer them all to one formation at a time when I had not stu- died their different organic remains. The cliffs north of Cape Rock afford excellent opportunities for ex- amining the beds of the calcareous division of the formation and for collecting their fossils in great abundance. The lowest beds which abut against the granite are nearly perpendicular, the limestones are much altered in character, and the shells contained in them are too much flattened to be identified ; among these a gigantic Arca is the most abundant. The next beds are seen at the Praia de Adrarga, those a little higher in the series at the Praia de Macams and Praia de Lagoa, at all of which localities organic remains are very abundant : the following lists contain those which I collected. With the single exception of Nerinea cylindrica, all the previously known species found in these localities belong either to the chalk or the greensand, and many of them are also found in the hippurite limestone close to Lisbon ; therefore these calcareous beds clearly belong to the subcre- taceous series, of which they form the middle portion. The Nerinea cylindrica is found in Germany among the oolites, but it was seen again near Coimbra in the upper beds of the subcretaceous series. Organic remains found in the cliffs at the Praia de Macams, north of the Cintra hills. Diadema rude, n. s. Artemis inelegans, n. s. Nerinza Titan, n. s. Diceras Favri, n. s. Olisiponensis, n. s. Exogyra plicata, Lam. Turritella Cintrana, n. s. Ostreea prelonga, n. s. Renauxiana, D’ Ord. Pecten quinquecostatus, Sow. Anomia convexa, Sow. Spheerulites Marticensis ?, D’ Orb. sp. levigata, Sow. —— undetermined. M 2 tod PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Noy. 21, At the Praia de Lagoa, near the preceding. Natica prelonga, Deshayes. Pholadomya Royana?, D’ Orb. At the Praia de Adrarga, north of the Cintra hills. Nerinza Archimedis, D’ Ord. Pecten striato-costatus, Goldf. cylindrica, Voltz. Trigonia caudata, Agassiz. (T. scabra, Pyramidella sagittata, n.s. Morris’s Catalogue.) Ostrza colubrina, Lam. At Fontanellas, north of Cintra. Cardium corrugatum, n. s. Both at the Praia de Adrarga and the Praia de Macams the lime- stones have been disturbed by various eruptions of trap, which appear to have burst out during the formation of the subcretaceous beds, with some of which they are very irregularly interstratified, while others are displaced by them: in connection with the trap is a mass of ar- gillaceous breccia, evidently of igneous origin and of considerable thickness, which interrupts the series of stratified deposits. These trappean beds are continued in a band round the Cintra hills, but they do not belong to one formation, as described m my former paper (Trans. vol. vi. p. 122), but pass through the different rocks which encircle the granite. The beds of the calcareous middle division of the subcretaceous series cover the country north of Cintra for many miles, extending beyond Mafra and Ericeira, and resting upon ferrugimous sands, which on the Caldas road are met with before reaching Torres Vedras. The lowest part of the subcretaceous series is largely developed in the district which lies to the north-east of Lisbon, bounded by the Tagus from near Verdelha to Villa Franca. The great elevatory movement which has thrown up the jurassic rocks of Monte Junto was continued with less intensity to the southward as far as Alhandra, raising up all the lower beds of the subcretaceous series into an anti- clinal of which the axis meets the Tagus at that place. This is seen in section No. 4 (fig. 5), which shows the position of the beds along the bank of the Tagus from Verdelha to Villa Franea. Fig. 5. Section No. 4. Bank of the Tagus near Alhandra. S.S.W. N.N.E. Verdelha. Alhandra. Villa Franca. Monte Gordo. SOS B 9g Limestone alternating with sandstone. Sand. 2 ee 25 Subcretaceous Series. 2 - a, Dn eB 29 Ss Tertiary. 2 The same series of beds is crossed by the section No. 5 (fig. 6), drawn nearly parallel to the last from Bucellas to Alenquer along a line of traverse which I examined in some detail. From Bucellas to Refugidos, a distance of about seven and a half 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 153 miles, the beds are crossed in a descending order: their dip is gene- rally to the S.W. at angles rarely exceeding 10°, but there are also some minor disturbances which spread them over a greater breadth of country than they would otherwise cover: the axis of elevation passes near Refugidos, beyond which spot the section re-crosses the same beds with a contrary dip in an ascending order. The following is the series seen in the first half of the section. Between Tojal and Bucellas the ferruginous sands and sandstones of the subcretaceous series are seen overlaid by the hippurite lime- stone which there dips 8.S.W. 15°: near Bucellas these sands dip S.W. 10°, and contain some unimportant beds of limestone: they closely resemble the upper division of the subcretaceous sands seen on the west of Lisbon, and appear to lie conformably under the hip- purite limestone; yet it is probable that this is deceptive, since the beds below these next to be described belong to a very low portion of the subcretaceous series, and differ from all those seen between Lisbon and the coast: therefore there must be a break in the continuity of the series, either between the hippurite limestone and the ferruginous sands of Bucellas, or between these and the calcareous series below them ; and the former is far more probable. After passing Bucellas the section crosses lower beds of sand and marl with some alternations of limestone. Below these are beds of argillaceous limestone containing some corals, alternating with marl : these pass downwards into a series of beds of grey limestone of con- siderable thickness, and so full of corals as to suggest the idea that they were originally part of a great coral reef: at Trancozo de cima on the line of our section their dip is S.W. 20°: these limestone beds are one of the principal features in the geography of this district, as they form the crest of the steep ridge of hills extending to the N.W. from the south side of Alhandra towards Sobral, on which were the principal defences of the lines of Torres Vedras. Below the preceding are seen alternations of sand and sandstone with some beds of coralliferous limestone overlying a great thickness of ferruginous sands which cover a large space of flattish country near Aruda, and in which there are also some beds of sandstone, marl and limestone. Below this arenaceous series lies a coarse white limestone which forms a saddle at Refugidos, and which is the lowest bed exposed on this line of section, and the lowest member of the subcretaceous series observed in Portugal. Yet from the irregular positions in which the beds of this series rest on the jurassic limestones, we cannot judge whether we have here really reached the bottom of the subcretaceous series. I received a rich collection of fossils, through the kindness of Senor Edwardo Augusto Boaventura, from the limestone beds lyig beyond Sobral towards Torres Vedras, which I believe to be the continuation of those seen on the last section at Trancozo de cima: it contains the following species, viz. :— ; Cidaris clunifera, Agassiz. Nerinza turbinata, n. s. Natic a prelonga, Deshayes. Artemis cordata, n. s. 154 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. | Novy. 21, Astarte discus, n. s. ' Ostrzea pustulosa, n. s. Cardium dissimile, Sow. Pecten Lusitanicus, n. s. Corbula Edwardi, n. s. Perna Lusitanica, n. s. Cyprina securiformis, n. s. rugosa, Goldfuss. Gervilia aviculoides, Sow. Tellina Sobralensis, n. s. Fittoni, n. s. Trigonia Lusitanica, n. s. Sobralensis, n. s. Mytilus Morrisii, n. s. muricata, Goldfuss, sp. The same gentleman sent me a fine specimen of Sphera corrugata of Sowerby, from the sandstones of the same neighbourhood ; this species has been republished by M. d’Orbigny under the name of Corbis cordiformis : it is a most characteristic shell of our greensand. The Portuguese specimen differs slightly in wanting the faint radia- ting lines seen on the English and French specimens, but is otherwise undistinguishable: this trifling difference will not constitute it a new species, as those lines vary much in our specimens. Between Enxarra dos Cavalheiros and San Sebastian, in beds pro- bably belonging to nearly the same part of the series, 1 found on a former excursion Trigonia muricata, Goldfuss, sp. Perna Lusitanica, n. s. The species in the above lists are so different from those found in the calcareous beds north of Cintra (p. 151), the only common species being Natica prelonga, that they show that the beds of the two lo- calities belong to very different positions in the subcretaceous series. From Refugidos through Alenquer to the northward, the section No. 5 (fig. 6) crosses the beds, just described, in the ascending order, dipping to the opposite direction of E.N.E. at angles varymg from 10° to 20°: I examined this part of the section im greater detail than the former. For easier comparison let us begin at the east end of the section and thus adhere to the descending order as before. The uppermost bed seen on this line is a loose sand in the valley of Cor- regado, beyond which we cannot carry the series, as the subcretaceous beds are lost to the eastward for some miles in a broad marsh which probably conceals a line of fault. Sandstones and sand of a light ferruginous colour, flanking the hills north of Villa Franca, lie next below the sands of Corregado, and are succeeded by the following :— Coarse calcareous breccia, seen to the north of Alenquer. Sand and sandstone with beds of micaceous flagstone, on the north side of Alenquer. Calcareous sandstone. Hard white compact limestone. Calcareous conglomerate. : Coarse coralline limestone containing also some shells: it caps the hill of Alenquer. This is obviously the same bed as that crossed on the former part of the section at Trancozo de cima, and like that is a true coral reef’;:it is perhaps 150 feet thick. Sand and sandstone, occasionally calcareous. Red and variegated marls. 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 155 Thin-bedded sandy limestone with shells. Sand and sandstone; at Verandas. Sand and marl with some beds of limestone; at Carnota. Coarse white limestone at Refugidos ; the lowest bed of the section. The following species were found in the limestone at Alenquer :— Cidaris clunifera, Agassiz. Nerinea Bruntrutana, Thurman. glandifera, Goldfuss. gigantea, D’ Hombres-Firmas. Nerinza annulata, n. s. grandis, Voltz, not of Goldfuss. The following were found in the calcareous beds below the Alenquer limestone, between two and three miles south of that town :— Nerinza turbinata, n. s. Corbula compressa?, D’ Orbigny. Nerita turbinata, n. s. Cyprina securiformis, n. s. Neritina bicornis, n. s. Perna polita, n. s. We must refer to the same bed the two great ridges of coralline limestone crossed on section No. 5 (fig. 6), the more eastern of which runs northward from Villa Franca through Alenquer, passing a little west of Otta, and contimuing to Alcoentre ; the other commencing on the Tagus on the south side of Alhandra and forming the line of Wel- lington’s defences to Sobral: their position, dipping in opposite direc- tions away from a common axis, their identity of mineral character, and the similarity of their organic contents, which in both cases con- sist principally of corals of which several of the species are the same, all show the identity of these limestones. Therefore in looking at the fossils with the view of settlmg the age of the deposits, we may unite the above lists with those at p. 154, and consider the whole to- gether. The lists present us with a most unusual assemblage of shells; of which Natica prelonga, Deshayes, Corbula compressa, D’ Orbigny, Sphera corrugata, Sow., Cidaris clunifera, Agassiz, Nerinza gigantea, D’ Hombres-Firmas, are only hitherto known in the lower greensand ; and to these Ner- nea turbinata will probably have to be added as a greensand species. Cardium dissimile, Sow., Gervilia aviculoides, Sow., have been found in England both in the lower greensand and in the Portland oolite. Nerinzea Bruntrutana, Thurman, Nerinza grandis, Voltz, not of Goldfuss, have been found in the Portland oolite. Cidaris glandifera, Goldfuss, Perna rugosa, Goldfuss, usually belong to the great oolite. Notwithstanding the admixture of oolitic species, those of the green- sand predominate, and lead me to class these beds im the subcreta- ceous series. The position and character of the beds also are in fa- vour of the same view. ‘They agree so closely in mineral character and underlie in so regular a sequence the rest of the subcretaceous 156 PROCEEDINGS OF THE GEOLOGICAL socreTy. [Nov. 21], rocks of the country, that it 1s quite uncertam where we ought to separate them ; and no good line of distinction, either geographieal or stratigraphical, has been observed between these beds and the calca- reous series north of Cintra. In fact it was only after my return home, and when I had examined all the fossils, that I became aware of the marked difference of age between them. In all my rambles while im Portugal, it never occurred to me to draw any lme between the two sets of beds. On the other hand, these beds rest unconformably on the jurassic limestone of Monte Junto, and present a striking contrast to all the Portuguese rocks of the oolitic period. We must therefore conclude that the sandstones and limestone here described belong to the lowest member of the subcretaceous series, which, following closely after the jurassic system without any mtervening break hke that caused in the north of Europe by the intervention of the freshwater formation of the Wealden, contams a large admixture of oolitic species. In comparing the Portuguese series of beds with that of England, we can find no parallels in England for the coralline limestone and associated beds of Alenquer and Torres Vedras, and must class the whole of this part of the series below our lower greensand, yet above our oolites, and thus perhaps as the marime contemporary of the Wealden formation. Ifthe Neocomian beds of the south of France and Switzerland should hereafter be proved to be distmetly older than the lower greensand of the north, which appears probable, we must then refer these Portuguese beds to the Neocomian series: m the mean time I have avoided using the term Neocomian, lest the beds m question should be confounded with the lower greensand of England, Germany, and the north of France, to which that name has been some- times unfortunately applied, and which is I think more modern than the Portuguese beds in question. JURASSIC SERIES OF Beps*. It has already been mentioned that the district covered by the sub- cretaceous beds is broken through in many places by limestones be- longing to the Jurassic or Oolitic period which rise uneonformably through the strata restmg upon them. These jurassic rocks occur in different parts of the country, forming independent lines of hills, so that their relation to one another is nowhere seen, and their relative age can only be deduced from the comparison of their organie remains. It appears from such evidence that there are in Portugal equivalents of nearly all the principal members of the oolitic series. I will de- scribe them in the order of their supposed age, beginning with the most modern. Chain of Limestone from Monte Junto to the Mondego. The Serra de Monte Junto, which lies nearly forty miles north by east of Lisbon, is the southern termination of a chain of limestone * Luse the term Jurassic in preference to Oolitic, because the limestones of Portugal have rarely an oolitic structure ; and the latter term might lead to a mis- construction as to the mineral character of the beds in question. 1849.| SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 1957 hills about ninety miles long and rarely more than one or two miles broad, which extends from Monte Junto northwards nearly to the Mondego, a few miles below Coimbra. This chain does not cross the Mondego, but as I only followed it northward as far as the spot where it is crossed by the Lisbon road on the level of Condeixa, I cannot state its exact termination, which I presume to be on the southern bank of the Mondego. The limestone at Monte Junto is about two miles wide and rises to the height of about 2000 feet* ; the beds are thrown up irregularly at high angles and dip away from the centre of the hill on three sides, towards the east, south and west, at angles varying from 40° to 80°; while on the north they are broken off from the rest of the chain by a narrow ravine called the Ferradouro, which admits of the passage of a tolerable road through the chain. No intrusive rock is here visible, but the force which elevated this long chain appears to have acted with great intensity at this spot, while it was diminished farther south, where the jurassic beds are not raised to sight and the subcre- taceous rocks are less disturbed. The section No. 6 (fig. 7) shows the position of the beds at Monte Junto: the effect produced at Alhandra, which is the most southern point to which this elevation can be traced, may be seen in section No. 4 (fig. 5) at p. 152. Bigs: 7, Section No.6. Across Monte Junto. (15 miles.) Sandstone. Jurassic limestone. Sandstone alternating with limestone. Marsh. The rock at Monte Junto is a hard, white or greyish argillaceous limestone with somewhat of a conchoidal fracture, and, in some of its beds, contains numerous Ammonites and fragments of Hncrinites which are not easily to be extracted: among the specimens brought away I have identified the following species, from which we may infer that this limestone belongs to the upper part of the oolitic system :— Ammonites Boucaultianus ?, D’ Orbigny. Ammonites polyplocus, Reinecke. colubrinus, Reinecke. tortisulcatus, D’ Orbigny. From Monte Junto the limestone chain runs for about thirty-five miles N.N.E. to Carvalhos: the road usually followed from Lisbon to Coimbra (called the Lstrada nova) runs on the east flank of the chain from Alcoentre to Rio Maior; after leaving the latter place the road inclines to the N.W. and crosses the chain at Alto da Serra, where the limestone is only about a mile broad and of inconsiderable eleva- tion. ‘The limestone beds here dip at angles of 60° to 70° to the eastward and are broken through by a mass of trap, as is shown in section No. 7 (fig. 8), and the jurassic limestone is overlaid uncon- formably on both sides by sands of the subcretaceous formation, which are elevated where they rest on the limestone to angles varying from 20° to 30°. * There is an establishment at the top for collecting ice for the supply of Lisbon. 158 PROCEEDINGS OF THE GEOLOGICAL society. [Noy. 21, Fig. 8. Section No. 7. Between Candieiros and Rio Maior. (5 miles.) Ww. Alto da Serra. Rio Maior. E. SANG Wa SX RAR = S CAXy SAE = = EFF AWSr WS SN Na Tee 2 Jurassic limestone. Basalt. = Ferruginous sands. See 2B ae Sua 2 oe Ra B58 & ee After crossing the limestone at Alto da Serra the road runs north- ward on the west flank of the cham for about twenty miles to Carvalhos, where the chain suddenly bends to the eastward. From Alto da Serra to Carvalhos the jurassic limestones dip eastward at angles varying from 30° upwards: the lowest beds seen are frequently some- what oolitic and associated with a fine-grained calcareous sandstone, which forms a beautiful white freestone for architectural purposes, © and has been used for the finest Gothic work in the church of Ba- talha: the middle and upper beds are of a hard, white or greyish ar- gillaceous limestone like that of Monte Junto, occasionally containing fossils, which I had no opportunity of extracting. During this part of its range we nowhere see on what the limestone rests, and its western flank, on which its lower beds crop out, is always covered by unconformable deposits of subcretaceous beds. I did not see the eastern side of this part of the chain. From Carvalhos the limestone chain suddenly turns eastward, pass- ing by Porto de Moz and Aire; beyond the latter place it rises into a lofty range called the Serra d’Aire. I did not follow the limestone through this part of its course. At the eastern end of the Serra d’ Aire the limestone range again turns northward and runs about N. by W. for nearly twenty miles to Redinha ; this part of the chain is less elevated and has not obtained a name, yet it forms a marked feature im the country. I crossed it at Val d’Ovos, about six miles from Thomar on the road to Leiria, and then after losing sight of it for some miles came upon it again before reaching Redinha, where the similarity of direction and general cha- racters left me no doubt of the identity of the beds. At Val d’Ovos the beds of limestone dip E.S.E. 10°, and cover a width of about a mile; the rock is a hard, white, compact limestone with a conchoidal fracture, and contains Belemnites, Turritellee, Corals, &c., which I had not time to collect. On the western flank of the chain the limestone is seen to rest on a soft ferrugmous sandstone containing minor beds of limestone ; these lower beds are very little exposed, being overlaid to the westward by unconformable beds of subcretaceous sands dippmg W. 3°. On the east of the chain the limestone is covered by a formation of ferruginous sands which appear conformable to it; these are described farther on. The position of the beds seen on this traverse will be seen in section No. 3 (fig. 4). Near Redinha the limestone stretches out in an easterly direction, and rises again into a high mountain ridge called imdifferently the Pa 1849.| SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 109 Serra de Rabacal or the Serra de Anciao* : the Lisbon road which had run parallel to the chain for some miles south of Redinha crosses the western prolongation of the limestone at that village: the beds dip N. 65°, and consist of a compact white limestone with a conchoidal fracture. North of the Serra de Rabacal the limestone resumes its former course of N. by W.: the road to Coimbra, after keeping for five miles on its west flank, crosses the chain to Condeixa: the beds here strike N. and are nearly perpendicular; the limestone is divided by some thick intervening beds of ferruginous sandstone. ‘The chain is here flanked on both sides by the sands of the subcretaceous series lying with slight inclination against the nearly perpendicular jurassic lime- stones. To the northward of Condeixa the limestone chain gradually sinks down and loses its importance; I followed it no farther and cannot state its exact termination, but I ascertained on another trip that it is not to be seen on the north bank of the Mondego. Throughout the long course of this limestone chain I was only fortunate enough to collect fossils at Monte Junto at its extreme ter- mination southward ; these indicate that the beds at that spot belong to the upper portion of the oolitic series : I think it probable that the rest of the chain belongs to the same part of the oolitic system, but this requires confirmation from farther observation. I have only visited a small portion of the district which lies to the east of the great limestone chain just described, and must return to it before I can be certain of having seen all the secondary formations of this part of Portugal. As has been already mentioned at p. 157, the southern end of the chain is encircled by the subcretaceous beds which flank its eastern side from Monte Junto to Rio Maior, beyond which I did not follow that side of the cham. ‘The same occurs at the northern extremity of the chain, its eastern edge being overlaid at Condeixa by subcre- taceous beds. The middle part of the jurassic chain is overlaid near Thomar by beds whose age I cannot fix, as I found no organic remains in them, and cannot compare them with any of the beds seen on the west of this cham. 'Thomar stands on a thick formation of a softish, friable, white limestone, occasionally brecciated, and passing in its upper beds into a white calcareous sandstone : the dip at Thomar is E. 3°: I found no trace of organic remains in this rock. A limestone of similar mineral character and usually nearly horizontal, reaches from Thomar to Torres Novas and Pernes. About three miles west of Thomar the white limestone just described is seen to rest on soft ferruginous sandstone and sands, covering a band about three miles wide. This sandstone rests on the jurassic limestone of Val d’Ovos, which dips at the junction E.S.E. 10°, so that the three * There is great confusion in the names of hills throughout Portugal, as the in- habitants of the opposite sides of a chain often give it different names, and those marked in the maps are frequently incorrect. 160 PROCEEDINGS OF THE GEOLOGICAL sociETy. [Nov. 21, strata appear to follow conformably (see anfe p. 158, and section No.3, fig. 4). It might therefore be thought that we had here the regular succession of the beds above the jurassic limestone of Val d’Ovos, yet I can hardly believe this to be the case, because the limestone beds at Val d’Ovos are of less thickness than in many other parts of the cha.n, and their series may therefore be incomplete ; and it is probable that if the Thomar beds were of an age immediately following on the jurassic limestone, they would more often be seen in connection with them. On the other hand, I cannot connect the Thomar limestone with the subcretaceous series, since I have seen no fossils in it, and it differs in mineral character from all the subcretaceous limestones observed to the westward; and the sands below it have no peculiar character which can guide us in determining their age. We must therefore leave the determination of the age of these beds until more information is collected about them. Limestone and Sandstone of Coimbra. The city of Coimbra stands on a limestone formation of great thick- ness, which rises unconformably from below the beds of limestone and sandstone of the subcretaceous period, as previously described (p. 146), and shown in sections, Nos. 1 and 2 (figs. 2 & 3). The upper beds of limestone are well seen at Fornos, three or four miles north of Coimbra, and again two or three miles to the south of the town on the Lisbon road ; they consist of thin alternating beds of hard argillaceous limestone and marl. From below these rises a hard, compact, grey limestone of great thickness, dippmg N.W. 30° to 45°, on which the town is built, and which extends for several miles on both sides of the river to the N.E. and S.E., forming nearly a semicircle. Organic remains must be rare, as I found no trace of them in several spots which I examined ; but in the Museum of the University of Coimbra are a few Ammonites from the upper beds of the limestone at Fornos, which led me to suppose on a very slight ex- amination that the limestone belongs to the upper or middle part of the oolitic series. At the upper part of Coimbra the limestone is seen to rest con- formably on a formation of ferruginous sandstone of very great thick- ness: the beds at the junction dip N.W. 30°. The following is the order of the beds of the sandstone formation :— 1. Hard calcareous conglomerate lying below the Coimbra lime- stone ; of little thickness. 2. Softer ferrugimous sandstonewith some beds of redand blue marls. 3. Ferruginous sands. 4, Ferruginous sandstone, containing numerous large blocks of in- durated slate, jasper, &c. Each of the three lower divisions is of great thickness, and the whole covers a breadth of about four miles, with a dip usually of N.W. 30°. The sandstone rests at Portella, four miles east of Coimbra, against a lofty ridge of micaceous schist which runs nearly north and south, and forms the eastern boundary of the secondary district. 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 161 Having only traced the Coimbra limestone and sandstone for a few miles from that city, I am not aware how far they extend either to the north or south. The Serra de Busaco has been described to me as consisting of a sandstone resting on micaceous schist, and as this range of hills is exactly on the line of the Coimbra sandstone, it is possible that the sandstone of Busaco may belong to the same forma- tion, although some specimens from that locality in the Museum at Coimbra have a metamorphic appearance. The limestone of Coimbra is separated from the jurassic limestone chain west of Condeixa by several miles of flat country covered by subcretaceous beds. Until the organic remains have been examined, it cannot be determined whether it is strictly identical with any of the other jurassic limestones of Portugal ; itis however not improbable that the Coimbra sandstone may prove identical with the sandstone which near Buarcos overlies the carboniferous series of Cape Mondego, which belongs to the oolitie period and will be next described. Till this is ascertained, we must be content to class the Coimbra limestone and sandstone in the jurassic system without determining their exact place in the series. Limestone and Coal of Cape Mondego. It has been mentioned p. 147, that below the red sandstone of Buarcos, referred to the subcretaceous period, there is another bed of sandstone, of the oolitic period, connected with the coal and lime- stones of Cape Mondego: a good section of these beds is seen along the coast between Buarcos and the extremity of the Cape, exhibiting the following series in descending order :— 1. Red sandstones with some beds of marl, commencing a little west of Buarcos, where they dip E.S.E. 15°; farther west the dip is S.E. 40°. These sandstones appear to be the uppermost jurassic rocks seen in this neighbourhood. 2. A series of sandstones of various characters containing a few thin beds of impure limestone, which become more important in the lower portion. 3. Coarse limestone about 100 feet thick with some partings of sandstone with abundance of small oysters and other shells, dip S.E. 40°. 4. Sandstone of great thickness with some thin beds of limestone, containing Ostrzea, Terebratula, &c., dip S.H. 40°; in the lower part the limestones are thicker and more frequent. . Carboniferous series, viz. :— . Alternate thin beds of marl, limestone and sandstone, 15 feet. . Coal, 2 feet. . Alternations of white limestone and grey marl, 12 feet. . Coal, 1 foot. Marl and sandstone, 5 feet. Coal, 6 inches. . Carbonaceous shale alternating with limestone, 6 feet. . Coal, 1 foot. Alternations of shale and limestone, 8 feet. e SeWwo gorge 162 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Nov. 21, j. Coal, 1 foot. k. Grey marl, 3 feet. l. Coal, 34 to 4 feet; the only bed worked. m. Grey marl, 6 feet. n. Alternation of grey marl and white limestone. 6. A formation of great thickness, consisting of thin beds of bluish earthy limestone alternating with blue marl, the beds varying from six inches to two feet thick; this series resembles in appearance our blue lias: dip S.E. 40°. These beds are crowded with Ammonites, some of which are above three feet in diameter, and other shells. 7. I did not see the beds underlying the above, but I was told that on the north side of the Cape a red marl rose from beneath them. The organic remains found in the limestones Nos. 3 and 4, above the carboniferous series, are few in number, and of species which only serve to indicate the middle part of the oolitic series; they are as follows: Corbula trigona, Remer. Ostrea solitaria, Sow. Dianchora bicornis, n. s. Perna mytiloides, Lam. Mytilus Beirensis, n. s. Terebratula bisuffarcinata, Schlotheim. There appear to be six beds of coal known, forming a total thick- ness of about ten feet ; the quality is bituminous, but it contains a good deal of sulphur, which prevents its general consumption, and the mines have only been worked on a small scale: the mines are close to the sea, but the coast is too rough to allow the coal to be shipped on the spot, and it is carted to Figueira for shipment. M. Michon, the director of the works, was kind enough to supply me with every information concerning them, and to give me some specimens of a Zamites, which was the only plant he had observed in the beds; it was found in the grey marl (m) immediately below the principal bed of coal. TI could find no traces of any other plants among the rubbish of the mine. : Mr. Morris has had the goodness to examine the specimens, and finds it to be a variety of Zamites gramineus, a well-known species of the carboniferous shales associated with the inferior oolite on the coast of Yorkshire. His remarks on the subject will be found in the Appendix. The followmg species were found in the beds of blue marl and limestone No. 6, below the coal series; they clearly prove that these beds belong to the lower part of the oolitic series :— Terebratula Astieriana, D’ Ord. Ammonites Henrici?, D’Oré. Beirensis, n. s. — Humpbhriesianus, Sow. decorata, Von Buch. macrocephalus, Schlotheim. perovalis, Sow. —— modiolaris, Luid. Ammonites anceps, Reinecke. oolithicus, D’ Ord. Bakeriz, Sow. —— plicomphalus, Sow. Bronguiartii, Sow. ——. Three species, supposed to be — discus, Sow. undescribed. —— hecticus, Reinecke. J Perhaps on farther examination, the sandstones which lie above the coal series of Cape Mondego may prove to be identical with the red sandstones below the Coimbra limestone. This seems the most pro- bable classification of these detached masses of jurassic rocks. 1849.| SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 163 Limestone of Montemér-velho, Se. The town of Montemdr-velho, on the north bank of the Mondego, twelve or fifteen miles below Coimbra, stands on the southern extre- mity of aridge of limestone about a mile wide running to the N.N.E., which is raised unconformably at a high inclination through the sub- cretaceous sandstone district (see section No. 2, fig. 3). At Montemdr the limestone beds form a steep anticlinal axis ; but this is merely local, as a little north of the town they all dip S.E. 30°, and further to the north E. 30°. The ridge is of moderate height and dies away gra- dually in its course northward. The limestone is rather soft, white, and very argillaceous ; it contains abundance of Ammonites, Belemnites, and other shells which prove it to be of the age of the lias: the following is the list :— Gryphea obliquata, Sow. Ammonites catenatus, Sow. Plicatula spinosa, Sow. — spinatus, Bruguiere. Terebratula bidens, Phillips. Stokesii, Sow. ornithocephala, Sow. Thouarensis ?, D’ Ord. —— punctata, Sow. Belemnites paxillosus, Schlotheim tetrahedra, Sow. Nautilus truncatus, Sow Ammonites brevispina ?, Sow. Turrilites Beirensis, n. s. Braunianus ?, D’ Ord. ? I only followed the limestone for four miles to the northward of Montemor, but in crossing from Aveiro to Coimbra, I observed a limestone of precisely similar mineral character at Vendas Novas, four leagues north-west of Coimbra: this place is about twenty miles N.N.E. of Montemor, and is consequently on the exact strike of the Monteméor limestone; several fossil shells are common to the two lo- calities, and the list of those found at Vendas Novas connects the limestone of that place with the lias. I feel convinced therefore that this is the northern prolongation of the Montemér ridge of limestone. The following species were found at Vendas Novas :— Plicatula spinosa, Sow. Ammonites spinatus, Bruguiere. Spirifer Beirensis, n. s. Stokesii, Sow. granulosus, Goldf. Belemnites exilis, D’ Ord. Terebratula tetrahedra, Sow. —— paxillosus, Schlotheim. carinata, Lam. The beds at Vendas Novas dip 8.E. 10°, and rise very little above the level of the surrounding subcretaceous beds, with which they might easily be confounded, if the organic remains were not carefully observed. Their position is shown in section No. 1 (fig. 2). The prolongation of the line of the limestone to the N.N.E. would bring it across the road from Coimbra to Oporto near Agueda, but as I saw no trace of such limestone in that neighbourhood, I presume that beyond Vendas Novas it sinks below the subcretaceous beds. There is however a patch of similar limestone at Mealhada on the Oporto road, about three leagues north of Coimbra: its characters are exactly similar to those of the limestones of Montemér and Vendas Novas, and like them it contains the Belemnites paxillosus in abun- dance, so that it is doubtlessly part of the same bed, though on a dif- ferent line of strike. 164 PROCEEDINGS OF THE GEOLOGICAL society. [Nov. 21, The limestone of Mealhada is slightly exposed and its relations are not well seen: on the north and south it is soon covered up by the subcretaceous sands, but I did not see how far it extended in the other directions. Inmestone of San Pedro and Shale of Ramathaé, near Cintra. These beds are described at p. 122 of my former paper on the Neighbourhood of Lisbon, where they are erroneously stated to be continued to the coast along the north side of the range of granite: this is not the case, as on that side of the hills they stop close to the town of Cintra, and the beds which overlie the granite between Cintra and the sea belong to the subcretaceous series. In the shale at Ramalhad some organic remains occur, but usually in very bad condition, as the great masses of trap interstratified with the shale have altered its characters and almost reduced it to the con- dition of slate: the following were found by the side of the road close to Ramalhaé :— Ammonites, too much crushed Avicula. for identification. Posidonia Bronnii, Goldf. t. 113. f. 7. Pleurotomaria. The last is a species found in the lias of Wirtemburg, with which for- mation we must connect this bed until we have better evidence re- specting it. I have nothing to add to the former description of the San Pedro limestone ; the only organic remains observed in it were amorphous masses apparently related to sponges, which are very abundant in the limestone a little to the north of San Pedro. The shells mentioned at p. 123 of the former paper belong to the subcretaceous limestones. As the shale of Ramalhad overlies the San Pedro limestone con- formably, it is probable that the latter also belongs to the period of the lias. The preceding rocks are all the deposits north of the Tagus be- longing to the oolitic series with which I am acquainted. I believe that the high limestone range of the Serra de Arrabida near St. Ubes will also prove to belong to the same series: but the limestone hills along the coast between Coimbra and Cape Espichel, formerly de- scribed as the Espichel limestone, belong with the rest of that forma- tion to the subcretaceous series. (See ante p. 151, and Geology of Neighbourhood of Lisbon, p. 121.) The preceding descriptions of the various isolated jurassic deposits of Portugal, coupled with the study of the organic remains contained in them, lead to the following comparison of these rocks with the oolitic series of England, viz. :— The limestone of Monte Junto and subjacent sandstone are to be classed with the upper portion of the oolites. The limestone of Coimbra, resting on a great thickness of red sands, will probably prove next to the above in the descending order. The calcareous beds above the coal of Cape Mondego, surmounted by red sandstone, belong to the middle of the oolitic series. 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 165 The carboniferous beds of Cape Mondego must be compared to the oolitic coal of Yorkshire: their position in the series seems nearly the same, and the same species of Zamites has been found in both. The beds of limestone and marl below the coal belong to the lower part of the oolitic series. The limestones of Montemdr-velho, Vendas Novas, and Mealhada must be classed with the lias. In this list we seem to have representatives of the principal oolitic beds; yet it is probable that there are other jurassic beds in the Pe- ninsula which have no representatives in the district here described ; for it has been usual to class in the oolitic system the grey limestone of Gibraltar and the Ronda hills which rests on a thick formation of brown shale, neither of which rocks can be compared with any of the beds above mentioned. The limestone of San Pedro near Cintra has more resemblance in mineral character to that of Gibraltar than any other of the Portuguese limestones, but it would be premature to class them together while so little is known of either. This comparison of the jurassic rocks of Portugal with those of England is only made in the most general sense: the rocks of the two countries differ in mineral character, being in England oolites alternating with blue clays, and in Portugal hard compact limestones separated by ferruginous sands: it is only in the organic remains con- tained in them that we find any true resemblance. Sandstones of which the age is not yet determined. To complete the account of my observations of the secondary for- mations of this part of Portugal, it only remains to describe certain beds of sandstone of undetermined age, which lie within the area of secondary rocks. Red Sandstone of the Vouga.—Following the road from Coimbra to Oporto we meet near Agueda with a coarse, friable, white sand- stone dipping S8.E. 5°, which passes into a softer reddish sandstone and ferruginous sand which continue to within a quarter of a mile of Serdad, where they dip S. 2° or 3°; these are the last beds of the subcretaceous series which are seen in proceeding northward along this road. Just before reaching Serdad6, a red sandstone, dipping S. 15°, rises from below the beds just mentioned and continues with some irregu- larities of dip to the north bank of the Vouga, where its continuation to the northward is concealed by gravel covering the country up to the appearance of the micaceous schist at Albergaria velha. The red sandstone of Serdad has no resemblance to any of the Portuguese rocks yet described; it is a fine-grained sandstone of a deep brick-colour, in well-defined beds separated by thin layers of marl, and closely resembles the new red sandstone of our Midland counties. It cannot extend far to the westward of Serdad, as near the mouth of the Vouga the subcretaceous sands rest immediately on the Silurian rocks. I have no information respecting its extent eastward, and must leave its age in doubt. Yet its position in contact with the older schists being similar to that of the sandstones of Busaco and VOL. VI.—-PART I. N 166 PROCEEDINGS OF THE GEOLOGICAL society. [Nov. 21, Coimbra, makes it probable that these sandstones may belong to the same period and form the outer line of secondary rocks, But the different mineral character of these deposits is against the supposition. There are still several parts of the district north of the Tagus which must be explored, before the series of the secondary formations of that part of Portugal can be considered complete. The narrow line of country between the schists of the Deucga and Zezere and the jurassic chain of Monte Junto, the Serra d’ Aire, &c., must be fully examined to establish the connection between the limestone of Thomar and the other formations described. The south bank of the Mondego must also be examined, as we may there hope to find some connecting links between the various members of the jurassic series. And the boundary of the secondary district north of Coimbra must be visited, to determine whether any connection exists between the sandstones of Serdad, Busaco, and Coimbra. Until these spots have been visited, the map here offered of the northern half of Portugal can only be regarded as a rough approximation. GENERAL REMARKS. Throughout the district here described there is less variety of mineral character than are usually seen in the same range of forma- tions ; the whole consisting almost entirely either of ferruginous sand. and sandstone or of compact limestone, with very little clay or shale. The sands, whether of the tertiary, the cretaceous, or the oolitic periods, have all nearly the same characters, and can hardly be di- stinguished by their appearance, and most of the limestones of the cretaceous, subcretaceous, and jurassic formations have a similar compact structure, white colour, and conchoidal fracture. These resemblances between beds of different ages add to the difficulty of the first geological survey of the country, and might be pleaded in excuse for many errors; but they are also in themselves facts of interest, which show that the Portuguese rocks were deposited under conditions which varied little during long periods: some of these conditions may be ascertained from the comparison of the characters of the rocks and of the animals which have been entombed m them. To commence with the lower beds: the fine-grained, argillaceous limestones of Montemdr, Vendas Novas and Mealhada, referred to the age of the lias, seem to have been deposited in deep, quiet water : Ammonites and Belemnites are abundant in them, Brachiopoda are also common, but the Lamellibranchiata are rare, and I only met with one solitary Gasteropod of the genus Pleurotomaria. The calcareous series below the coal at Cape Mondego has also the characters of a deep-water formation: the limestones are argillaceous and alternate with fine marls; the fossils found in them were Tere- bratule and Cephalopoda, the Ammonites bemg in extraordinary abundance. The change from the beds just mentioned to the carboniferous series resting on them is so sudden, that it must be attributed to the upheaval of the bed of the sea soon after the deposition of the Cape 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 167 Mondego limestone, as we rise from limestones and marls full of Ammonites to a series of marls and sandstones, including several beds of coal and containing land plants, but without any remains of marine animals. And in the beds above this carboniferous series the organic remains present a complete contrast to those seen in the beds below the coal, being of the genera Ostrea, Perna, Dianchora, Corbula, and Mytilus, all probably inhabitants of moderate depths, with only one species of Terebratula and no Cephalopod whatever. To these succeed coarse sands and grits, which, like the Mollusca just men- tioned, indicate the existence of a shallow sea at a moderate distance from land. And this is the character of all the subsequent deposits, excepting the great calcareous formations of Coimbra and Monte Junto, containing Ammonites and Belemnites, which were probably formed in deeper water. The whole of the rocks of the subcretaceous series appear to have been formed near the land and in shallow water. The limestones in this series bear only a small proportion to the sandstones. In the lower division there are large accumulations of corals, which are so abundant at Alenquer and in the corresponding beds between Alhandra and Sobral as to form complete reefs: the species of Ostracee, Car- dium, Mytilus, &e., together with Gasteropoda often of large size, also indicate deposits in seas of moderate depth, and the bed of lig- nite found in several localities proves that land was then not far distant. The negative evidence is to the same effect; in these beds I only found one specimen of Belemnite and not a single Ammonite, while the Terebratule are very rare and confined to the lower part of the series. The hippurite limestone with subordinate beds of calcareous marl appears to have been formed in quieter water, but the organic remains found in it indicate that it was deposited in a sea of moderate depth: they are principally Lamellibranchiata, Gasteropoda, and Rudista, without any Cephalopoda or Brachiopoda. © Thus after the deposition of the older jurassic limestones nearly all the secondary rocks of this district appear to have been deposited in shallow waters, and for the most part in rough seas near acoast. But we cannot appreciate all the bearings of these facts till we know the characters of the formations of the same age in other parts of the Peninsula. The proportion between the new and the previously known species of organic remains is very different in the different secondary forma- tions of Portugal: mm my collection only about 45 per cent. of the fossils from the hippurite limestone are described species, in the sub- cretaceous beds 53 per cent., and in the jurassic series about 84 per cent. As the species of secondary European fossils hitherto described are nearly all from the north and middle of Europe, the proportion of described species in a Portuguese formation shows how many of the species are known to have been common to the seas of the north and south of the Pyrenees at the geological epoch in question. Before we can safely conclude from the above statement that the N 2 ne a ea aa re, 168 PROCEEDINGS OF THE GEOLOGICAL society. —[Noy. 21, inhabitants of the earlier seas had a wider range north and south than those of later periods, we must take into consideration the habits of the animals of which we find the remains, and see whether the differ- ences are due to greater powers of migration of the species of one formation over those of others; or whether they depend on the dif- ferent depths below the surface at which the shells may be supposed to have been originally deposited; for we may expect to find most widely diffused the remains both of animals capable of swimming out to sea and of the inhabitants of deep water, which being less affected by climate than those living near the coast, can live equally in very different latitudes. The followmg table shows the number of the previously described and of the new species of the four orders of Mollusks, which include most of the Portuguese secondary fossils, in each division of the geolo- gical series; and also the proportion per cent. which the previously known species bear to the whole im each case. In the Hippurite limestone :— paaeik pete’ pebeitinya Gasteropoda ......seceeeaes DIVE Z3ts 2 is 20 Lamellibranchiata ......... Were By -cheedesge 41 Brachiopoda .....cceesseeee —— ces eeeeee —— sssehyaas — Cephalopoda ......ces.eeee — _ waecbeeee ——" Shaina == In the Subcretaceous series :— Gasteropoda ....00....seeee EEO wincdane LRT pear 38 Lamellibranchiata .......+. De iilscndsee, LO eeeneaes 56 Brachiopoda ......sssseeees ig eee aa roa 100 Cephalopoda ..............- a ere a inane — In the Jurassic series :— Gasteropoda ...... eee eee nae a) eee — Lamellibranchiata ......... Phi ernie ee. 75 Brachiopoda ......ceeess+ EO) steecenes 2 aceeceeee 83 Cephalopoda ...... cesses Gag We oceetee a 86 PSEA shin seeteene 86 61 If we disregard the formations and look only to the character of the animals, we shall find that of the Portuguese specimens collected, 30 per cent. of the Gasteropoda, 54° 4, 55. 55. _+~Lamellibranchiata, 86°. 3, °,, 3, 4 Brachiopeda, 6° 3 gy ep aalepeaa are known to the north of the Pyrenees: thus it appears that the swimming Cephalopods and the Brachiopods are diffused equally widely, which can only be attributed to the latter living at great depths. The Gasteropods prove to be the most local, which is doubtless due to their mostly living near the shore. The Lamelli- branchs, which include species confined to the coast with others living at greater depths, hold an intermediate place in the scale. It is also to be remarked that the Brachiopods and Cephalopods are found in company and almost by themselves in the jurassic deposits ; while in the cretaceous and subcretacous beds, in which Gasteropods and Lamellibranchs are abundant, the two former orders are almost entirely wanting. 1849.] SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 169 It seems from this analysis that the different depth of water under which the beds were formed has been one principal cause of the dif- ferent proportions in which we find northern species entombed in the Portuguese formations. Yet after making every allowance on that head, there seems to have been a somewhat greater power of migration in the earlier periods, as the known species of Lamellibranchs are proportionally more numerous in the jurassic than in the subcretaceous beds, and in these than in the hippurite limestone, and the known Gasteropods of the subcretaceous beds are proportionally almost twice as numerous as those of the hippurite limestone. I have dwelt at some length upon these speculations, because I believe that this is the first time that any large collection of secondary fossils from so southern a part of Hurope has afforded the opportunity of comparing the inhabitants of the southern seas of the secondary periods with those of the secondary seas of our latitudes. The secondary collections hitherto made in Europe extend over many degrees of longitude, but have been very limited in latitude, and have therefore come from countries with moderate differences of climate. I cannot conclude without expressing how much I am indebted to Mr. Morris for the assistance he has given me in the examination of the whole of my collection of fossils, and to Mr. Edward Forbes for his kindness in examining and describing the Echinodermata brought from the beds here described. 170 PROCEEDINGS OF THE GEOLOGICAL socizTY. (Nov. 21, APPENDIX. General List of the Organic Remains found in the Secondary Strata of Portugal. Genus and Species. References. Formations. Localities. PLANTA. ZAMITES gramineus, Phillips, sp. Geol. Yorksh.|Jurassic ssssscesseeeees Cape Mondego. var. Mundee. | vol.i.t.10.f.23 post, t. 26. fe ok ECHINODERMATA. Brissus subdepressus ...|Forbes, t. 25.f.6. ........./Subcretaceous ...... Figueira. SQUEIZER scp Siss9: Forbes, t. 25. f.5. .........(Hippurite limestone .|Near Lisbon. CipARIS clunifera ..,......|Agassiz, Echinod. de la/Subcretaceous.........|)Alenquer; near Suisse, t. 21. f. 19-22. Sobral. glandifera ...... Goldfuss, t. 40.f.3 .......4. Subcretaceous......... Alenquer. leviuscula ...... Agassiz, Echinod. de la|Subcretaceous......... Figueira. Suisse, t. 21. f. 18-20. DIaADEMA Lusitanicum ...|Forbes, t. 25.f.4. .........;subcretaceOuS......... Mamarosa. TUGG iach ecenceia Forbes, t. 25. f.3. ........./Subcretaceous......... Praia de Macams. EcuInus Olisiponensis ...|Forbes, t.25.f.1. .........|Hippurite limestone ./Near Lisbon. EcCHINOPSIS subuculus ...... Forbes, t. 25.f.2. .........,;Subcretaceous......... Figueira. TOXASTER Couloni? .......[AGASSIZ .......006 eeaiteraiess Subcretaceous.........|Figueira. CONCHIFERA. ANOMIA ; COMVEXA Tancareess Sowerby, Geol. Trans., 2nd|Hippurite limestone .|Papel. Series, vol. iv. t. 14. f. 7.|Subcretaceous......... Praia de Macams. laevigata .....000. Sowerby, Geol. Trans., 2nd|Subcretaceous......... Praia de Macams. Series, vol. iv. t. 14. f. 6; d’Orbigny, Pal. Franc. i Crét. t. 489. f. 4—6. ARCA Moutoniana...... d’Orbigny, Paléont. Franc.|Hippurite limestone .|/Papel; Lisbon. T. Cret. t. 321. Olisiponensis ...|n.s., t. 14. f. 1. ......ec0ee. Hippurite limestone .|Lisbon. Passyana? ......\d’Orbigny, Paléont. Frang.|Hippurite limestone .|Lisbon. T. Crét. t. 327. f. 1-2. ARTEMIS Cordata’ vices MiSep Ci QLh roe eree ees Subcretaceous......++: Near Sobral. elegantula ...... TeiSes its MAR aon mnwacmmcare ae Hippurite limestone .|Papel. inelegans ......... Ta Sipy Ue 20 ete ee a calueellsh len Subcretaceous......... Praia de Macams. ASTARTE GISCUS) ses ieseeaees Ms Sepite SST AOS tec Subcretaceous.......+. Near Sobral. AVICULA Olisiponensisi.. lsiS. belie deal esapreeveres Hippurite limestone .|Lisbon. CAPRINULA DYCVIS MEO. eenesk ss tSe tte Peds ok OC Be Metae ce Hippurite limestone .|Lisbon. BOISSYis.ceeose eee: d’Orbigny, Paléont. Franc.|Hippurite limestone .|Lisbon. T. Crét. t. 540. post, t. 16. 1849.| SHARPE ON THE SECONDARY ROCKS OF PORTUGAL. 171 Genus and Species. References. Formations. Localities. pemreesaee | sees CAPRINULA (con- tinued). d’Orbignii ...... Me Sis ts 1G. tl Oc 25h Biaen Hippurite limestone ./Lisbon. Doublieri.........|Caprinella, sp. d’Orb. Pal,|Hippurite limestone .|Lisbon. Franc. T. Crét. t. 541, post, t.17.£.3 & 4. CARDIUM COLTS ATUM, .04+0. (Me Sy t. 14. £. Be conrceveenss Hippurite limestone .|Lisbon; Bucellas Subcretaceous......... Fontanellas. dissimile? ...... Sowerby, Min. Con. t. 553./Subcretaceous....,.... Near Sobral. fee Olisiponense ...\n. S., t. 14. f.4 ......,..+.-|Hippurite limestone .|Lisbon. CorBuLa GAEINALA bees re any d’Orbigny, Pal. Franc. T./Subcretaceous.,.......; Near Leiria. Crét. t. 388. f. 3- compressa ..,...(d’Orbigny, Pal. Franc. T.|Subcretaceous......... Near Alenquer. Crét. t. 388. f. 6-8. COstgetagen: a dceces We Seq. tare beta marucapackens Subcretaceous......... San Pedro de Mu- riel. Edwardi ......... West bears teas da voates sane Subcretaceous.......+. Near Sobral. THI OND, «gaia ieccare Roemer, Oolith, t. 8. f. 5 .JJurassic .....00..-000 Cape Mondego. CyPRINA COLOTUT os cesses TeSep Ung in ep al iBannore cede Hippurite limestone ,/Lisbon. PROUOSA vcec soe Wa Sib alos Wool wean eea.® Hippurite limestone ,|Lisbon. securiformis...... WMeSsg Geto tevlm Ov cigkcleaies Subcretaceous......... Near Sobral ; DIANCHORA Alenquer. bicornis ........- Ths Ses. be @Oe ke 4 G6 Secceaceds- JUYASSIC ...00. eguue nan Cape Mondego. DIcERAS AWN sata cise sree’ n.s., t.15.f.3. and t. 20.f. 9.| Hippurite limestone .|Lisbon Subcretaceous......... Praia de Macams. EXoGYRA CONICA ......... ....sowerby, Min, Con. t.605.|Subcretaceous.........,;Mamarosa ; Sar- f. 1-3, jeuto-mér ; San Sylvestre; Fi- gueira. Olisiponensis ..,jn. s., t. 19. f. 1. & 2......, Hippurite limestone ,.|Lisbon. DUCAEAL sss < At ere : ¢ ~ Senet wp wregeeanttet a Rant err receenrWe pba a IE al 5 pings . E A St Vid oh E i Yo pig oa Giga aa ial | ; Diss simak aes 13 BIS eR yma SS ips Ss ~~ ay - = LDAP, id bear h - i LL FT pe 2 B 22 Tt 2d 7>)7 fecit. SLD CSpwerbr Ure Be Ty) AI A MECEL os Geol. Journ. Vol VI. £1.20 SLD CUSowerby fectt. oe ial es ¥ 6 Roe oe : El she * : et . ; ; t = ¢ ss “ i a ; ory 4 J , ‘ + 7 - ; = ; - ‘J ‘ ‘ ' me ; Md * - j , ‘ ‘ ’ Ny i . ‘ f Woe 7 je { 7] “ 4 < ‘ Bats M ot t + 8 ‘ ‘ ‘ ’ 7 mt = eA. hy ct ; i , nee a -e . z t x = ; ‘ / d ) ae » \ 7 P ‘ > ‘ aa ty o oy v € Quart. Geol. Journ. Vol. VL. Ft. 2. SDe C. Sowerby fectt. Quart. Geol. Journ. Vol VI. Fl. 22 TDe C. Sowerby reer 4 JS De C Sowerby fect. 0 / Ouart. Geol. Journ. Vol VI. PL 24 an eee RUAN BNE SLe C Sowerby tecit PDE. Sowerby fect , » 9 ee Ouart. Geol. Journ. Vol VI £26. aS SMe C Sowerby tect. 1849.] MORRIS ON MAMMALIAN REMAINS AT BRENTFORD. 201 Fig. 3. Diadema rude, from the subcretaceous beds. Fig. 4. Diadema Lusitanicum, from the subcretaceous beds. Fig. 5. Brissus scutiger, from the Hippurite limestone. Fig. 6. Brissus subdepressus, from the subcretaceous beds. PLATE XXVI. Fossils from the Jurassic Series. Fig. 1. Mytilus Beirensis. Fig. 4 & 5. Dianchora bicornis. Fig. 2. Spirifer Beirensis. Fig. 6. Turrilites Beirensis. Fig. 3. Terebratula Beirensis. Fig. 7. Zamites gramineus. DrEcEMBER 5, 1849. Count Achille de Zigno, of Padua, Robert Aglionby Slaney, Esq., M.P., Ernest Noel, Esg., William Lee, Esq., and Cornelius Nicholson, Esq., were elected Fellows of the Society. The following communications were then read :— 1. On the Age of the Upper Tertiaries in ENGLAND. By SearRxes V. Woop, Esq., F.G.S. [This paper was withdrawn by the author with the permission of the Council.] 2. On the Occurrence of MAMMALIAN Remains at BRENTFORD. By Joun Morris, Esq., F.G.S. Tue discovery of mammalian remains in the vicinity of Brentford has long been well known to geologists. It is more than thirty years since Mr. Trimmer obtained a valuable collection from this district. An account of these remains and of the conditions under which they were found, was published with illustrations in the ‘ Philosophical Transactions’ for 1813. In 1838 I collected from an excavation, for the reservoir of the water-works near Kew Bridge, numerous horns and bones of the ox and deer, and bones of the elephant ; traces of lignite also, but no remains of shells, were observed. I should not, therefore, have laid before the Society the following remarks, had not the progress of the railway-works in that neighbourhood exposed some sections, which not only fully corroborated previous observations, but afforded some new facts connected with the history of the deposit, as well as a considerable number of mammalian bones, for the pre- servation of which we are indebted to the active zeal of Mr. Thomas Layton, jun. _ The sections alluded to occur about 100 yards north of Kew Bridge, where a branch or rather loop line of the South-Western and Windsor Railway passes under the high road at the entrance to Brentford. ‘The section here given occurs north of the bridge, where the entrance to the station is completed. This section gives the principal features of the deposit, as exposed in the deepest part of the railway cutting, which extended about one- 202 PROCEEDINGS OF THE GEOLOGICAL SocieTy. |[ Dec. 5, 8 1. 1. Vegetable mould; 1 foot. Ds 2. Brickearth, a fine brownish loam; 4 feet. 3. Fine sand, mostly stratified and obliquely la- minated, with occasional wavy and irregular veins of small gravel ; 6 feet. 4, Sand, with light-coloured clay and irregular gravel, containing bones; 6 to 8 inches. 5. Ferruginous gravel and sand, with patches of clay ; 1 foot. 6. Clayey sand and sandy gravel, with occasional large flintstones, partly ferruginous at the upper part, containing bones and shells; 1 to 2 feet. 7. Ferruginous sand and gravel; about 6 inches. 8. Light clayey sand and ferruginous gravel, with boulders of quartz, granite, rock with am- monites, &c., also bones, &c. of ox, deer, &c.; 6 to 7 feet. 9g. London clay. third of a mile, and presented great variations in the order and rela- tive thickness of the sands and gravel, which pass into one another in a very irregular manner. No remains were, I believe, found in the brick earth and sand (2 and 3); the sand (3) throughout its whole extent was stratified and obliquely laminated, some of the layers being more ferrugmous than the others, and occasionally interstratified with veims of small gravel; the ferruginous gravel (5) is of less regular thickness, the upper surface bemg sometimes eroded and the hollows subsequently filled with a coarse greyish sand and light clay (4), containing bones ; the clayey sand (6), also containing bones, is the chief depositary of the shells, which were generally in a perfect state of preservation, the Anodons retaining their usual brown epidermal covering. The chief mass of the ferruginous gravel (7) consisted of rounded and angular chalk-flints of various sizes; but occasionally intermixed with them were a few pebbles and small boulders of other rocks, as London clay septaria with Teredine, indurated greensand, sand rock with ammonites, fragments of pyritical ammonites (Oxford clay 2), coarse reddish sandstone, white quartz, granite, &c. The bones, although occurring in all the layers below No. 3, were most abundant in the lowest stratum; on one side of the railway, a vein of sand, containing shells, was observed, intercalated with this gravel bed. Below the gravel bed is the London clay upon which the whole deposit rests, but the depth of the clay was variable and not accurately determined. 1849.| MORRIS ON MAMMALIAN REMAINS AT BRENTFORD. 203 The section above given, although differmg in minor details, pre- sents similar general characters to those recorded by Mr. Trimmer as occurring in the clay-pits examimed by him, one of which is more than a mile distant ; there can be little doubt, therefore, of the syn- chronism of this deposit; the later excavations have also afforded, with the exception of the hippopotamus, similar mammalian remains, with the addition of the great cave tiger and reindeer. The shells were but few in number in this locality as compared with the more eastward deposits in the Thames valley. After a careful search, and with the assistance of Mr. Layton, I could only find the following eight recent species :— Bithynia impura. Limneus stagnalis. Succinea amphibia. Pisidium amnicum. Valvata piscinalis. Cyclas cornea. Limneus auricularis. Anodon anatina. Not even fragments of Cyrena trigonula and Unio littoralis, now extinct (at least m England), were observed, although these species are common at Ilford, Grays, Erith, Stutton, &c., where they are associated with a large number of our present indigenous, fluviatile and ter- restrial mollusca. From the general features, both physical and fossil, of this deposit, which has now been traced over a considerable area in the neigh- bourhood, I am inclined to consider it as resulting from fluviatile action, and that at a period when a river, far more deep and extensive than the present stream, flowed along the valley. Even allowing the base of the deposit to be level with high-water, a river of considerable depth must have existed, to have accumulated and arranged twenty feet of solid materials, and that not in a very violent manner, for scarcely any of the bones exhibit the least trace of attrition, most of them being perfect, and many belonging to the same individual ; thus rendering it nearly certain that they could not have been drifted from any great distance, but were probably the remains of those animals which lived and died not far from the banks of that stream, where they subsequently became entombed in the same deposit with the fluviatile mollusca. The mammalia associated together in this deposit consist of the elephant, rhinoceros, hippopotamus, aurochs, short-horned ox, red deer, reindeer, and the great cave tiger or lion; the discovery of the latter animal (a well-preserved ulna of which has been identified by Prof. Owen) is highly interesting; hitherto, I believe, the remains of this carnivore have (with one exception, viz. that of North Cliff, Yorkshire) been obtained only from the ossiferous caverns. The occurrence of the reindeer is a point equally interesting and important, not only from its remains being but rarely found in this country (two instances only being cited by Prof. Owen), but from the association of this arctic form with other mammalia generally considered indicative of a warm climate. Thus, its co-existence with the great cave tiger, from the presumed tropical character of the genus to which the latter belongs, might be regarded as somewhat 204 PROCEEDINGS OF THE GEOLOGICAL society. [ Dec. 5. anomalous ; on this pot however Prof. Owen*, speaking of the genus Felis, justly observes, ‘“‘ There is no genus of mammalia in which the unity of organization is more closely maintained, and in which, there- fore, we find so little ground in the structure of a species, though it may most abound at the present day in the tropics, for inferrimg its special adaptation to a warm climate.” With regard to the relative age of this deposit, I had formerly considered it} as synchronous with the numerous mammalian beds which occur throughout the valley of the Thames. The evidence, however, is not very satisfactory, masmuch as the presence of pebbles apparently derived from the drift might lead to the inference of its being posterior to that period, and the absence of the Paludina mar- ginata, Cyrena trigonula, and Unio littoralis, may distinguish it from the beds at Ilford, Grays, Erith, &c. Still, perhaps, sufficient value has not been assigned to certain specific mammalian remains of the later tertiary deposits, as tests of their relative position; nor can we feel the full importance of slight specific differences until we are acquainted with the true and exact value of the succession of the different groups of mammals, during the more recent geological changes; and the geologist should use great caution in marking the exact bed from whence the remains that he submits to the comparative anatomist are derived, even though he obtain them from the same valley. Independently however of these considerations, there is a singular fact, which must not be overlooked as connected with the present subject, viz. that it is generally along those valleys where the present drainage of the country is effected that we find the most extensive deposits of mammalian remains and recent shells; and consequently very little alteration can have taken place as regards the physical configuration of the country since the period of their deposition. List of Mammalia found at Brentfordt. Elephas primigenius. Cervus tarandus. Bison priscus. Rhinoceros tichorhinus. Bos longifrons. Hippopotamus major. Cervus elaphus. Felis spelza. * British Fossil Mammalia, p. 162. + Mag. Nat. History, 1838, p. 539. t Mr. Thomas Layton, jun., has presented a collection of the mammalian re- mains to the British Museum. 205 DONATIONS TO THE LIBRARY OF THE GEOLOGICAL SOCIETY, November |st to December 31st, 1849. I. TRANSACTIONS AND JOURNALS. Presented by the respective Societies and Editors. AMERICAN Journal of Science. Second Series, vol. vill. no. 24. Philosophical Society, Proceedings. Vol. v. no. 43. Athenzeum Journal, November and December 1849. Chemical Society, Quarterly Journal. No. 8. Cornwall, Royal Institution of. Thirtieth Annual Report, 1848. France, Société Géologique de, Bulletin. Deux. Série, tome vi. feuilles 27-34. Indian Archipelago, Journal of the. Vol. ii. no. 9. Trish Academy (Royal). Transactions, vol. xxii. part 1. Proceed- ings, vol. iv. part 2. Leeds Philosophical Society. 28th and 29th Annual Reports. Philadelphia, Academy of Natural Sciences of, Journal. New Series, vol. i. part 3. ' Proceedings, vol. iv. nos. 9 and 10. Philosophical Magazine, November and December 1849. From R. Taylor, Lsq., F.G.S. Il. GEOLOGICAL AND MISCELLANEOUS BOOKS. Names in italics presented by the Authors. Brongniart, A. 'Tableau des genres de Végétaux Fossiles. Burmeister, Dr. Hermann. Die Labyrinthodonten aus dem bunten Sandstein von Bernburg, zoologisch geschildert. Erste Abth. Trematosaurus. VOL. VI.—PART I. Q 206 DONATIONS. Dana, J. D. United States Exploring Expedition, during the years 1838-42. Geology, with Folio Atlas of Plates. Hausmann, J. F. L. Studien des Goéttingischen Vereins Bergman- nischer Freunde. Band 5. Heft 3. Hennessy, Henry. Abstract of Papers read before the Geological Society of Dublin. Hogg, John. Remarks on Mount Serbal, bemg the true Mount Sinai, with Map. Morris, John. Note on the Genus Siphonotreta, with a description of a new species. Observations on Mr. Hancock’s paper on the Excavating Sponges. Pictet, F. J., et W. Roux. Description des Mollusques Fossiles qui se trouvent dans les Grés verts des Environs de Genéve. 2nde livraison, Gasteropodes. Stevenson, W. F. 'The Composition of Hydrogen and the Non-de- composition of Water demonstrated. Zigno, Achille de. Atti verbali della Sezione di Geologia, Mineralo- gia e Geografia, estratti dal volume degli atti della IV. Riunione degli Scienziati Italiani, ch’ ebbe luogo in Padova nel Settt® 1842. ————. Introduzione allo Studio della Geclogia. Part 1. —e eee Sulla Giacitura dei Terreni di Sedimento del Trivigiano Memoria. Nota intorno alla Non-Promiscuita dei Fossili fra il Bian- cone e la Calcarea Ammonitica delle Alpi Venete. Sul Terreno Cretaceo dell’ Italia Settentrionale Osserva- — zion. Sopra due Fossili rinvenuti nella Calcarea dei Monti Pa- dovani Memoria. Zoology of the Voyage of H.M.S. Samarang, during the years 1843- 46. No. iv. part 2, and no. 5. From Messrs. Reeve. THE QUARTERLY JOURNAL OF THE GEOLOGICAL SOCIETY OF LONDON. PROCEEDINGS OF THE GEOLOGICAL SOCIETY. DECEMBER 19, 1849. The following communication was read :— On Craters of Denudation, with Observations on the Structure and Growth of Volcanic Cones. By Sir Cuarues LYELL, Pres. Geol. Soc. In the first edition of my ‘ Principles of Geology,’ published in 1830 (vol. i. ch. 30), I explained the grounds of my objection to the theory previously advanced by Baron von Buch to account for the origin of the Caldera of Palma, the Gulf of Santor, and other bowl-shaped cavities of large dimensions, for which he proposed the name of “Craters of Elevation.” I regarded the circular escarp- ments surrounding these vast cavities as the remnants of cones of eruption, the central parts of which had been destroyed, and I con- ceived that the removing cause had been chiefly, if not wholly, en- gulfment. In the second edition of my ‘Principles,’ published in 1832, or two years later, I discussed more particularly the origin of the single deep gorge, which in Palma, Barren Island, and other so-called elevation- craters, forms a breach in the circular range of cliffs, surrounding the central cavity. This ravine or narrow passage I attributed ‘‘to the action of the tide during the gradual emergence from the sea and up- heaval of a volcanic island’’ (ch. 22. vol. i. p- 452), ene I at the VOL. VI.—PART I. 208 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. _[ Dec. 19, Fig. 1.—View of the Isle of Palma, and of the entrance into the cen- tral cavity or Caldera.—From Von Buch’s ‘‘ Canary Islands.” WWSS Fig. 2.—Mup of the Caldera of Palma and the great ravine, called ** Baranco de las Angustias.’—From a Survey of Capt. Vidal, RN; AS3z. — AS ; QU ; LNOTEN 5 If N\ ‘ \ IN WAM WER sey hs SC N WS SS SS = WUE N \\ = Se 9 SS=i Juan Graje = ZS i ZH ZL Pt., 780 ft. high, * astxil y SSX LE LL Z EL 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 209 same time alluded to its analogy to the single passage leading into the lagoons of many annular coral islands or Atolls. Although I then distinctly announced this theory in regard to such narrow ravines, the idea had not occurred to me that the same de- nuding power of the waves and tides, which were thus appealed to as adequate to remove the rocks once filling such deep gorges, must of necessity have exerted a like action on the walls of the craters them- selves. I well knew from the excellent description published by Von Buch of Palma, an island to which I specially alluded, that the long and deep chasm called Baranco de las Angustias, which alone breaks the continuity of the rocks enclosing the caldera, and was bordered on both sides by steep cliffs, was not less than between six and seven miles in length, bemg at its upper extremity 2000 feet or more in depth. I ought therefore, in consistency, to have inferred, that the same ocean, which I supposed to have stood successively at various levels, and in the course of ages to have ground down and carried away so vast a volume of rock, from this channel, must during the same long period have excavated a part of the hollow once occupied by similar and equally destructible materials. By referring to the annexed map, fig. 2, from Capt. Vidal’s ‘ Survey of Palma,’ the reader will observe that the sea cliff at Point Juan Graje, 780 feet high, now forming the coast at the entrance of the great ravine, is continuous with an inland cliff which bounds the same ravine on its north-western side. No one will dispute that the pre- cipice at the base of which the waves are now beating, owes its origin to the undermining power of the sea. It is natural therefore to attri- bute the extension of the same cliff to the former action of the waves exerted at a time when the relative levels of the island and the ocean were different from what they are now. Of late, after fully reconsidering the subject, I have come to the conclusion that the origin of a great part of the Caldera of Palma was probably due to denudation, and that the same holds true of other analogous cavities, such as are seen in Teneriffe, and many volcanic islands, so well described by M. von Buch in his classical work on the Canaries. Santorin in particular, which has been selected as furnishing the best type of a crater of elevation, owes, I believe, the chief part of the extension of its circular gulf to denudation, the whole crater together with the surrounding rocky islands having subsided bodily since the denudation, so as to be now half submerged in the waters of the Mediterranean. Before I proceed to treat more im detail of this and other volcanos, T shall offer a few preliminary remarks, to prepare the geologist for the reception of the views about to be proposed. In the first place it is admitted, that many of the volcanos, in which these large crateri- form hollows exist, have been formed wholly or in part beneath the level of the sea; 2ndly, the quantity of solid rock assumed by me to have been worn down and carried away through a narrow channel by the waves and currents (as the islands emerged) is by no means great, when contrasted with the masses removed from many elliptical areas, which have been called valleys of elevation, such as the Wealden, or R 2 210 PROCEEDINGS OF THE GEOLOGICAL society. [ Dec. 19, the smaller valley of Woolhope. The latter has been described by Sir R. Murchison, and more recently by Mr. Phillips*. It is 44 miles in diameter, and resembles in size as well as in some of its leading features the Caldera of Palma, the beds, in the boundary eliffs encircling the excavated space, dipping im all directions outwards, and the cliffs for that reason retaining more easily their steepness or verticality. ordly. If the crater of a submarine volcano be upraised and begin to emerge, the sea will still flow into it on its lowest side, and the circular basin will then be filled and emptied alternately by the flux and reflux of the tide, or by the rise of water blown into the opening by prevailing winds, and then fallig again as soon as this force ceases to act, by which means a passage will be kept open, the crater bemg scoured out like estuaries which have narrow entrances. On the efficacy of this last mode of aqueous erosion I must particularly insist, as it aids us more than any other in comprehending the theory of denu- dation-craters. The Basin of Mines in the Bay of Fundy illustrates the manner in which a large bay, communicating with the ocean by a narrow strait, may be filled and half-emptied every tide, so that the waves and currents may sweep out in the course of centuries a vast volume of mud and sand, and produce on all sides of the bay long ranges of cliffs annually undermined, several hundred feet per- pendicular, some composed of soft red marl, others of hard quartzose grit, and others of columnar basalt. The Bay of Fundy it is true would not present, if it were upraised and laid dry, so circular a hol- low as the so-called crater of elevation, but there are numerous coves on a part of the coast of Dorsetshire which are as perfectly circular, if not more so than the Gulf of Santorin or the Caldera of Palma, and in which the single breach effected by the sea on one side is not larger in proportion to the entire girdle of encircling cliffs. These cliffs moreover, which every geologist attributes exclusively to the denuding action of the sea, are precipitous, and most lofty at the head of the bay or farthest from the entrance, where they consist of imelined strata of chalk. Lulworth Cove, which is 1300 feet across, is the most perfect example (see fig. 3). In this case the hardness of Figt 3: Coast of Dorsetshire. IN {i \ | MUI ww AAG mvt Nt Uy Ai win Zz, ro SSS Lulworth Cove. barrow Cove. Cove. * Murchison, Silurian System, Part I. p. 428, and J. Phillips, Mem. of Geol. Survey, vol. ii. p. 167. 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 21 the Purbeck and Portland strata prevents the waves and tides from breaking down and widening the seaward barrier, and the compara- tive softness of the vertical or highly inclined beds between the bar- rier and the chalk at the head of the bay promotes the enlargement inside the entrance. Athly. But there are certain valleys in Australia, described by Mr. Darwin, which from their depth, the steepness of their boundary cliffs, and the narrow gorges by which the sea has entered to hollow them out, afford perhaps a still more striking explanation of the mode of operation, to which I shall refer in great part the origin of such craters as Palma, the Gulf of Santorin, and others of similar large di- mensions. [allude to those valleys near Syduey in New South Wales, by which the great platform of sandstone, 1200 feet thick, is pene- trated. The traveller, says Mr. Darwin, when walking over the sum- mit plains, finds himself suddenly at the brink of a continuous line of lofty cliffs, so perpendicular, that he can strike with a stone the trees growing at the depth of between 1000 and 1500 feet below him. At the distance of several miles he beholds the opposite line of cliff, rising up to the same height with that on which he stands, and formed of the same horizontal strata of sandstone. So continuous are the bounding lines of cliff, that to descend into some of these valleys it is necessary to go round twenty miles; but what is still more remarkable, these valleys, although several miles wide in their upper parts, generally contract towards their mouths to a mere chasm, impassable to man or beast. Thus the gorge of the Cox river is only 2200 yards wide, and about 1000 feet in depth. Mr. Darwin at first asked himself whether the mass of stone removed from these great amphitheatrical depressions, had not subsided ver- tically ; but was compelled to abandon this notion on considering the narrow promontories which projected from the platforms ito the valley. He was also struck with the resemblance of the inland ba- sins or bay-like recesses to the present bold sea-coast, where there are similar recesses forming fine harbours, connected with the sea by narrow mouths, sometimes not more than a quarter of a mile in width, the cliffs being formed of similar sandstone. 5thly. It must also be remembered that in the coasts of volcanie islands, such as Palma, Santorin, St. Helena, and others, there are lofty cliffs of basaltic and other igneous rocks, often traversed by dikes which have been formed by the undermining action of the sea, and are still wasting away. Mr. Darwin has particularly dwelt on the enormous cubic mass of hard rock pared off by the swell of the At- lantic from the coasts of St. Helena, where there are perpendicular cliffs from 1000 to 2000 feet in height, consistmg of basaltic strata traversed by dikes (p.91). Inthis island also, as well as in St. Jago and Mauritius, he has observed in his volume on Volcanic Islands, p. 93, that the ring of basaltic mountams forming what is commonly called “the crater of elevation,’ must once have been nearly or quite continuous, although now broken. Some very wide breaches have, he observes, been evidently effected by the denuding action of the waves. All these islands, he concludes, have been elevated in mass. 212 PROCEEDINGS OF THE GEOLOGICAL sociETy. [Dec. 19, It will be seen therefore that to account for the excavation of certam large crateriform cavities in some of these same islands, I am merely introducing a force, which is already acknowledged to have been most energetically exerted in destroying extensive masses of rock formerly environing the spaces called elevation-craters. Having said thus much of the denuding or removing power, I shall next offer a few prefatory remarks on the mode of origin of the dome-shaped volcanic masses, of which I consider the boundary rocks of every denudation-crater to be the basal remaims. Mr. Scrope, writing in 1827, attributed the formation of a volcanic cone chiefly to matter ejected from a central orifice, but partly to the injection of lava into dikes, and to that force of gaseous expansion, the intensity of which im the central parts of the cone is attested, he said, by the local earthquakes which often accompany eruptions*. But it was reserved for M. E. de Beaumont, seven years later, to poimt out that the extent, uniform thickness, and compact structure of many sheets of basaltic lava, which constitute the flanks of many volcanic cones, such as Etna and Somma, leave very little doubt that they were ori- ginally poured out on a surface, much less inclined to the horizon than the angle at which they now slope. ‘To the same observer we are indebted for most valuable researches into the laws governing the flow of lava streams, the result of which he published after his visit to Etna in 1834. In his memoir on that mountain he endeavoured to prove that the numerous up-filled fissures or dikes are the evi- dence and measure of the elevation of the distended volcanic mass, consisting of sheets of lava and alternating conglomerates, and that the whole mountain is probably undergoing upheaval bodily from time to time, as often as it is traversed by star-shaped cracks, such as oc- curred during the eruption of 1832. In the later edition of my ‘ Principles+’ I referred to the labours of M. de Beaumont, and admitted that a greater part of the beds ex- posed in the precipices of the Val del Bove were ‘originally less in- clined, some of them perhaps much less so thannow.” At the same time I attributed the change of position to the “ successive fracturing, distension and upheaval of the cone,’ not to a sudden upthrow. Whether I still underrated the amount of unequal elevation by which certain beds are believed to have been tilted and changed from their pristine horizontality, I know not, but I feel as convinced as ever that I was right in continuing to reject the hypothesis of elevation-craters, of which MM. de Beaumont and Dufresnoy have been the able and strenuous advocates. When repeating in my different publications the objections previously urged by myself and cthers to the theory of Von Buch, I always cited the argument so strongly insisted upon b M. Constant Prévost, that if beds of non-elastic materials had yielded suddenly to a violent pressure directed from below upwards, we should not find a circular cavity with an even and unbroken rim, but an irregular opening where many rents converged, and these rents * Geological Transactions, 2nd Series, vol. ii. p. 341. + See edition of 1847, p. 401. 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 213 would now be seen breaking through the walls of the crater, and widening as they approached the empty central space*. Instead of any such open rents being visible in the walls of the Caldera of Palma, and in analogous crateriform cavities, we invariably find dikes or up- filled fissures, in which, as well as in tortuous veins, often forming a reticulated mass, the melted matter was clearly consolidated before the boundary cliffs were formed. The origin therefore of all such rents, numerous as they are, was wholly antecedent in date to the whole movement assumed as the cause of the elevation-crater. I have also in every edition of my works uniformly contended, in com- mon with Messrs. Scrope, C. Prévost, and others, that in mountains like Etna, Mont Dor, and the Cantal, we must look to that area where we now find the greatest thickness of lava and fragmentary ejections as the chief and permanent source of the alternating lavas, tuffs, scorize, and conglomerates composing the volcanic cone. The increase of the cone, so far as it consists of such superimposed igneous products, I compared to the exogenous growth of a tree, and in Etna and some other volcanos a series of superimposed slopmg beds has been piled up successively to a thickness of more than 4000 feet. We may call the injection of lava, and the distension and upheaval caused by the hydrostatic action of imprisoned vapours, to which M. de Beaumont has justly attributed much greater importance than I had previously conceded, or even than Mr. Scrope had assumed, the endogenous growth of the mountain. The intensity of this last- mentioned mode of increase is much greater in the more central than in the marginal parts of a volcano. For this reason we perceive near the margin or base of the cone that the lava and beds of scorize, as they gradually thin out, become intersected by fewer and fewer dikes, until these at length entirely cease to appear. Not only the number, but the size or width also of such dikes may often be seen to augment as we approach nearer and nearer to the central axis of the cone. Other generalizations on the origin and growth of cones and craters I shall defer to the sequel, as they will be best explained when I am commenting on the structure and probable mode of formation of par- ticular volcanos. PALMA. To one of the most remarkable of these, the island of Palma, I shall first allude. Von Buch has given us a graphic picture of what seems to be the most splendid and perfect example yet discovered of a huge and deep cavity, surrounded on all sides by a circular range of precipices which are 4000 feet in height, the beds dipping out- wards in all directions from the centre of the void space, which is about six geographical miles in diameter. The sloping beds consist chiefly of basalt alternating with conglomerates, composed in part of rolled masses of similar basalt. Here, therefore, we seem to have evidence of the subaqueous origin of a portion at least of the volcanic accumulation, while the highest part of the cone may have raised * Principles of Geology, ch.24. Mém. de la Soe. Géol. de France, tomeii. p. 91. 214 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Dec.19, itself, like Stromboli, and been exposed to the power of the waves. The inclination of the beds corresponds to that of the external slope of the island, being greatest towards the central hollow axis, and less steep near the sea. The intersecting dikes and veims are more and more abundant as we approach the crater, and therefore are most numerous where the slope of the beds is greatest. This is seen by aid of a transverse section of the entire succession of beds obtained in the cliffs bounding the one deep baranco which extends from the sea-coast to the crater. The origin of this deep ravine, a pheenome- non, says Von Buch, common to all “ craters of elevation,” and which recurs in the Great Canary, the island of Amsterdam, Barren Island, and, as we shall presently see, in Santorin, is left wholly unexplained by the hypothesis of sudden upheaval, unless we are prepared to assume that the same engulfment which swallowed up the central mass once filling what is now the hollow axis of the cone, has ex- tended to one side and one side only of the encircling zone of rock (see figs. 1 & 2, p. 208). Had there been several such gorges inter- rupting the circular and solid girdle which encloses the caldera, it might have been argued with some plausibility that such openings were due to the fracture of a non-elastic mass, which, however slowly upraised, could not expand and stretch, because even the less com- pact beds were fortified by ribs of the unyielding stony substances constituting the dikes. According to Von Buch, the mass upheaved in Palma fell back into the middle of the crater *, but sections seem wanting to show that the nature and structure of the bottom of the great hollow, where the ground rises very considerably in the centre of the caldera, are such as to lend countenance to this conjecture. The theory of denudation briefly stated at the commencement of this paper may explain not only the excavation of the caldera, but may account for its enormous size; and what is still more satisfactory, it absolutely requires the existence of a great baranco through which the abstracted rocky ma- terials or the missing portions of the cone have been swept out m the form of mud, sand and gravel. To refer the evacuation of the Caldera of Palma to explosion is inadmissible, for the same reason that M. de Beaumont has very properly rejected a similar hypothesis in regard to the Val del Bove on Etna, viz. because if so vast a volume of solid matter had been blown out into the air, it must when it fell down again have formed a dense bed of fine dust and angular fragments of stone, such as does not envelope the surface or exterior slope of the island. Sections of such an envelope would have been seen in the ravines or barancos, some of them 500 feet deep, which radiate to- wards all points of the compass, from the rim of the caldera to the sea, without however interrupting by their upper or shallower extre- mities the continuity of thatrim. As to the origin of these numerous barancos, M. von Buch is of opinion, that the torrents now flowing in some of them, even when the snow melts in the higher parts of the truncated cone, are too inconsiderable to cause them. He sup- * Description des tiles Canaries, p. 285. French edition, 1836. 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 215 poses them to have been produced when the island was suddenly up- raised, an hypothesis which I regard as inadmissible, because they never intersect the rim of the escarpment. If on other grounds we conclude that the elevation of Palma from the sea was gradual, we are bound to reflect whether the waves may not have contributed as well as torrents acting on rocks of unequal hardness to produce such ravines. SANTORIN. After I had indulged in the above speculations in respect to the origin of the Caldera of Palma, it occurred to me that the circular gulf or crater of Santorin offered a serious objection to the theory of denudation, because the boundary cliffs of the Gulf plunge suddenly ito very deep water. It is clear that while the land and sea stand at their present relative levels, the bottom of a crater 1000 feet deep could never have been hollowed out by the denuding force of waves and currents: but learning from my friend Capt. W. H. Smyth, that a new survey of Santorin had been recently executed, under the di- rection of Capt. Graves, I obtained, through the kindness of Capt. Becher, of the Hydrographical department of the Admiralty, an un- published chart, in which the soundings around and between this group of islands are laid down with great minuteness. Capt. Smyth also allowed me to consult a paper recently communicated to the Geo- graphical Society by Lieut. Leycester, who has been actively engaged, together with Lieut. Mansell, in the late survey. From these sources I have derived data by which it will appear that the case of Santo- rin, so far from militating against, is, on the contrary, strongly con- firmatory of the denudation theory, besides throwing no small light on the mode in which new volcanic mountains are gradually formed in the centres of many craters of denudation. The largest of the three islands surrounding the circular gulf of Santorin is called by Lieut. Leycester, Thera (see Map, fig.4). It is of a horse-shoe form, and has an external coast-line of eighteen miles. It is three miles wide from east to west, and, as MM. Boblaye and Virlet ascertained, consists of volcanic matter, with the exception of its southern part, where Mount St. Elias (fig. 4, D), 1887 feet high, occurs, being com- posed of limestone and argillaceous schist. The volcanic mass is quite independent of these older formations, and abuts against them. It is made up of alternating beds of trachytic lava, tuff, and conglomerate, which, as M. Virlet has shown, have a gentle dip outwards from the centre of the Gulf, towards which they terminate abruptly in a steep and often perpendicular cliff. That these beds, and similar ones occurring in the other two eastern islands, Therasia and Aspronisi, are the lower portions of a great cone or flattened dome, the centre of which has disappeared, was the opinion arrived at by MM. Virlet and Boblaye, in the French ‘Expedition of the Morea.’ In the cliffs, says M. Virlet, the separate masses of trachyte and obsidian are seen to mould themselves into the inequalities of previously existing surfaces formed by fragmentary and conglomerate beds. Neither the solid nor the incoherent masses constitute wide-spreading sheets, but are dis- 216 PROCEEDINGS OF THE GEOLOGICAL society. [Dec. 19, Map of Santorin in the Grecian Archipelago, from a Survey in 1848, by Capt. Graves, R.N. The soundings are given in fathoms. Fig Lp “9 2 30°" 29 ia Lat, 36°2VN A. Shoal formed by submarine volcanic eruption in 1650. C. Mansell’s Rock. B. Northern entrance. D. Mount St. Elias, 1887 feet high. Fig. 5.—Section of Santorin, in a N.E. and S.W. direction, from Thera through the Kaimenis to Aspronisz. . Thera. Sea. Aspronisi. The three Kaimenis. « Fig. 6.—Part of the Section fig. 5, enlarged. The three Kaimenis. Old. New. Little. 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 217 continuous and dove-tailed into each other, except one grand deposit of white tufaceous conglomerate, which forms the capping of all the islands. M. Virlet found that the vesicles or pores of the beds of tra- chyte were lengthened in the several directions in which they would naturally be drawn out, had they flowed as melted matter towards different points of the compass from the summit of a cone, the axis of which once occupied the centre of the gulf. From the structure, irregularity, and interrupted nature of the beds, and their moderate dip, not exceeding in Thera three or four degrees, there seems no reason to assume that they have undergone any change from their original position, except such as may have arisen from general up- ward and downward movements of the whole island. . The length of the outer coast-line of the three islands taken together is about thirty miles. Aspronisi is not more than a mile in circuit, and only 300 feet high. It is surrounded by dangerous shoals for a distance of about a third of a mile, as if it had recently wasted away by the action of the sea; and in the geological chapter before cited of the ‘Expedition of the Morea,’ it is stated that the waves are con- stantly preying on the marginal cliffs of the three islands, so as to en- large the intervals between them*. ‘That these islands were once united has been the conclusion of every geographer and geologist who has seen them; but the late survey by Capt. Graves may be said to have set the question for ever at rest. The subaqueous rim of the crater has been traced, first from Cape Acrotiri in Thera to Aspro- nisi, the depth of water varying from five to ten fathoms, and then from Aspronisi to Therasia, where there is the same depth, one spot, called Mansell’s shoals (fig. 4, C), beg no more than nine feet under water. Throughout the circuit of these two lines of shoal, constituting the unbroken subaqueous rim of the crater, the water was found to deepen suddenly on the inside, or towards the gulf; but in the third channel, called the northern entrance (fig. 4, B), about a mile wide, between Therasia and the nearest part of Thera, a remarkable breach is disco- vered in the continuity of the submarine walls of the great bowl. Near the land on both sides the water is shallow for a certain distance, as if the cliffs had wasted away. Then there is a plunge to 100 fathoms, and in the middle of the passage no less than 195 fathoms, or 1170 feet. This deep ravine in the bed of the sea is significantly spoken of by Lieut. Leycester, as the “‘door into the crater.” It is evi- dently the “‘ portillo’’ of Santorin, or its “‘ Baranco de las angustias.” It is the single chasm through which, when the Santorin archipelago stood more than 1000 feet higher, the contents of the vast crater of denudation were swept by the sea; and it is a remarkable fact, that its depth precisely agrees, to within a few inches, with the greatest depth discovered, after minute soundings, in any part of the gulf. It is also important to remark, that outside the islands, where the sound- ings deepen much more gradually than in the inside of the gulf, they reach in some places, as for example about two miles south-west of Aspronisi, to depths of 250 and 260 fathoms, showing that the Gulf * Expédition de Morée, vol. ii. p. 259. 218 PROCEEDINGS OF THE GEOLOGICAL Society. [Dec.19, of Santorin, deep as it is, is still shaliower than some of the adjoin- ing parts of the Mediterranean, and might, if upraised, present a dry crater connecting by a chasm with the sea. The greatest depth of the crater or gulf according to the late sur- vey was found to be between the shores that are highest; that is to say, between that part of Thera where Merivali is situated and the opposite cliffs of Therasia, which are about four miles distant. Here the soundings reached 213 fathoms. The height of the escarpment at Merivali is 1171 feet, that of the high land in Therasia 936 feet, the cliffs on both sides above water and below beimg very steep and in great part perpendicular. If therefore, says Lieut. Leycester, the crater were empty, the observer looking down into it from Merivali would behold a frightful abyss 2449 feet in depth, the bottom con- sisting generally of reddish or brownish clay, and the opposite side, or that of Therasia, would be only 235 feet less deep. A vast circu- lar cavity, nowhere less than 1200 feet deep, would be seen to be eighteen miles in circumference, the encircling cliffs broken in one place, and one only, by a ravine 1170 feet deep. The walls of the great crater would be nearly twice as high on the north-east as on the south-west side, on the whole very uniform in outline; but at Scau- ~ rus a narrow promontory would jut out from the steep cliff, about one-third of a mile into the gulf. In the middle of this great caldera (the waters bemg drawn off) a single volcanic mountain would appear, bearing the same relation to the surrounding deep sea and circular escarpment which the Peak of Teneriffe bears to its moat and bastion, as described by Von Buch, or which the active volcano in the centre of Barren Island bears to the marine channel and outer girdle of rocks by which it is surrounded. This central mountain (see sections figs. 5 & 6, p. 216) is about five miles and a half in circumference at its base, and is surrounded on all sides by deep water. Its longest diameter is about two miles, m a direction from north-east to south-west. It has five summits, which spring from a ridge at the height of about 1000 feet from the bottom of the crater. Three of these summits, called the Kaimenis, rear their heads above the present level of the waters. The north-eastern, called the Little Kaimeni, or little burnt island, is 222 feet above water, formed by eruption in 1753. There is a cone on it having a crater eighty feet deep, and on the north side of it a considerable bank, of large blocks of lava and ashes. The top of this cone is 1550 feet above the base of the mountain. The middle, or New Kaimeni, was produced during erup- tions in 1707 and 1709. It was composed at first of two parts, which were afterwards united. Its summit consists of a cone, which rises 351 feet above water. Its sides slope at an angle of 33°, and its shape, well delineated by Bory St. Vincent in plate 37. fig. 2 of the Morea Expedition, is precisely that of cones of single eruption-im Auvergne, or on the flanks of Etna. The crater on the summit is eighty yards in diameter, according to Lieut. Leycester, and the highest point of the cone is 1629 feet above the bottom of the abyss. The south-western island, or the Old Kaimeni, is 328 feet above water, or twenty-three feet lower than the highest of the other peaks. The channel which 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 219 separates it from the New Kaimeni is in one part 100 fathoms deep. The two other summits spoken of are submerged cones, one occur- ring on the north and the other on the east of the Kaimenis, the north- ern peak being twenty-four fathoms under water and 1158 feet high, the eastern peak twenty fathoms, giving it a height of 1251 feet above the bottom of the crater. Their summits are flat. They spring from the same ridge as the Kaimenis, and the whole mountain with its five summits nearly bisects the gulf in a north-east and south-west direc- tion, a direction not assigned to the Kaimenis in maps published pre- viously to the late survey (see Map, fig. 4. p. 216). From a history of the successive formation of different parts of this central volcano, or volcanic ridge, we derive the knowledge of facts of great geological importance, for we are taught that the Kai- menis owe their present elevation not only to the heaping up of cones of fragmentary matter, but to the bodily though partial upheaval of portions of the trachytic mass, bearing on its surface a thin layer of pumiceous ash, containing marine shells. The rise of this bed of pumice, first called the White Island, in the year 1707, is on record, and it has been examined of late years by Mr. Edward Forbes, who made a collection of the marine shells contained in it, among which were both univalves and bivalves, of the genera Pectunculus, Arca, Cardita, Trochus, and many others, all recent species of the Mediter- ranean *, in a fine state of preservation, and implying that the sea- bottom on which they lived, when enveloped by a fall of ashes, was between twenty and thirty-five fathoms in depth. The state of the bivalves, their shells double with their valves closed, with the epi- dermis remaining, indicated that they had been suddenly destroyed. We know therefore from the habits of these mollusca, as observed b Mr. Forbes in the Mediterranean, that an upheaval of at least 220 feet was required to bring them up to the level of the sea, above which they now rise to the height of five or six feet. This bodily upheaval of a certain mass of ashes does not appear to have affected the other two islands equally, if at all, at the same period, still less to have ex- tended to the outer islands; for if so, such ports as Phira, built on the water’s edge, on a talus of fallen fragments from the vertical cliff, would have been carried upwards. We have here then an indispu- table proof, in the Gulf of Santorin, that in the gradual reconstruc- tion of a voleanic mountain in what was previously the original centre of eruption, large masses of solid matter may be lifted up in mass, 150 or 200 feet, and sustamed at that height, while other parts of the volcano in the immediate vicinity do not participate in the move- ment. This power of the lava or gases to carry upwards, to a height of 200 feet or more, a stratified deposit, which M. Virlet considered as having floated like cork on the top of a denser fluid, is a pheeno- menon which may perhaps aid us in comprehending how, in some steep isolated hills, ike the Puy Chopine in Auvergne, the volcanic mass may have been uplifted, together with large fragments of the granite on which it reposed, as MM. von Buch, Le Coq, and Dau- beny have held. We learn that when the new island Neokaimeni * British Association Report for 1843. 220 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. { Dec. 19, was formed in 1707, it went on increasing irregularly, and sometimes was lowered on one side while it gained height on the other. At different periods also during the growth of the island, isolated rocks rose up in the sea at different distances from its shore, some of them appearing and disappearing at intervals. There were many evidences of eruption before a visible crater was at length formed, so that we may infer that an intumescent mass of pasty or fluid trachyte was forcing up the top of the hill, as we see lava-currents, when they meet with an obstruction, swell up because they are encased by and con- fined within a solid exterior, the sides of which often slope at an angle of more than 40°. The large open rents seen on the surface of the Old Kaimeni or Hira attest the distension of that island, durmg the injection of lava beneath it. In a word, the whole history of these central islands shows that they owe their origin to the successive and intermittent action so characteristic of volcanos, and lends no support to the hypothesis of a smgle paroxysmal explosion, by which either a gigantic mountain or crater can be formed at one effort. Had the denuding action of the sea never removed the central portions of the ancient cone, all those masses of brown trachytic lava and pumice which have now gone to the production of the central volcano, called the Kaimenis, would have been expended partly in the filling of fis- sures with melted matter, forced upwards, partly in the outpourimg of lava, and ejection of scorize from a permanent central vent. For in some cases, as in the Sandwich Islands, we see craters much loftier than that which crowns Etna emit streams of lava of enormous vo- lume. But it happens more commonly in volcanos, that, as they gain in height, the pressure of the central column of lava overcomes the resistance offered by the sides of the cone, so that the latter give way at some points. ‘There can therefore be little doubt that a large pro- portion of the materials now composing the Kaimenis would, if the great dome had remained entire, have been emitted in the form of lateral cones. Had this occurred, the volcanic strata now encircling the Gulf of Santorin would have been intersected by veins and dikes, whereas none of the geologists who have visited Santorin make any allusion to such dikes, and Mr. Edward Forbes tells me he observed none of them in any of the three outer islands, Thera, Therasia, and Aspronisi. We must consider therefore these three masses as the basal remains of a large dome or cone, so far removed from the ori- ginal centre of eruption as not to have been subject to injection from below. As the theory of denudation requires us to suppose in the case of Santorin an oscillation of level, that is to say, first the gradual rise of a cone of submarine origin and secondly its partial submergence, it is worthy of remark that Lieut. Leycester states that on the east side of Thera there is a road now twelve fathoms under water, which formerly led from Perissa to Camari, and which was above water before the earthquakes of 1650, in which year a volcanic eruption occurred in the sea about three miles and a half north-east from Cape Colombo in Thera, where vapour and flames were thrown out and the sea was covered with pumice, and where after some months a shoal (fig. 4, A, 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 221 p. 216) was left having ten fathoms water over it. This shoal Captain Graves surveyed, and the soundings were found to deepen im all di- rections, demonstrating the existence of a submarine conical emmence. Lieut. Leycester was also told of houses seen at the bottom of the sea on the east of Thera, near the site assigned for the ancient Eleusis ; and a similar statement was made of ruins under water, at the base of the steep cliffs of Therasia; but as on this coast inside the gulf the water deepens very suddenly from the base of the cliffs, an earthquake may have thrown down some buildings ito the sea. It is therefore unsafe to draw any positive conclusion in favour of subsidence from such data. When we reflect on the oscillations of land which have occurred within the last eighteen centuries, on the site of the Temple of Serapis near Naples, we may well imagine much greater movements of 1000 or 2000 feet to have happened in the course of the geological period during which Santorin may have been exposed to denudation. I may observe however, that if a general upward movement should now recommence in this archipelago, so that the crater should emerge at the rate of a few feet or yards in a century, the waves would have power to tear down the rim where it is now perfect at a slight depth under water, namely between Therasia and Aspronisi and between the latter island and Thera. The same force which is now denuding the cliffs of those islands would readily undermine rocks of diversified and partly incoherent composition, during a continual change of level from century to century. The effects of this slow waste would appear in the form of wide breaches in the outer wall or ring of volcanic rocks, so that the condition of Santorin would approach much more nearly than now to the broken basaltic escarpments of St. Jago and Mauritius, as described by Mr. Darwin. There has been some controversy as to whether the fundamental argillaceous schist seen in the south-eastern part of Thera, or the main island, crops out also in Therasia; but if so, it would not affect the theory of denudation above proposed; for we must conclude with Mr. E. Forbes that the original voleano of Santorm was formed in the bed of the Mediterranean, on which the limestone mass and ar- gillaceous schist of Mount St. Elias, now 1887 feet above the sea, formed a submarine mountain, against which the south-eastern base of the great cone abutted. It is therefore very possible, though we have as yet no certain data for the fact, that the same pre-existing in- equalities of the sea-bottom may cause similar ancient rocks to crop out in a part of Therasia. ISLAND OF ST. PAvL. The voleanic island of St. Paul, situated in the midst of the Indian Ocean, lat. 38° 44’ south, long. 77° 37' east, and surveyed in 1842 by Captain Blackwood, R.N., may serve in some degree to aid us in con- ceiving how such an archipelago as that of Santorm may have been formed (see figs. 7, 8, 9). In that portion of the volcano, probably a very insignificant part of the whole, whether in height or area, which at present emerges above the level of the wide ocean, we have a crater 222 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [ Dec. 19, Pie: Map of the Island of St. Paul, lat. 38° 44' S., long. 77° 37' E., surveyed by Capt. Blackwood, R.N., 1842. a> NS S Ww WY wy) sabi en yw ag 4 x AN S2y Ay anion. A, \ E Entrance nearly dry at Le, \y My Nine-pin q LY Wy m - \ ieee, rock. & gw BS NW wy, Wg low water ——S>S= —— —— = —S— i te = if tay, yy e a Wot ce RS j —<\ 6 a7] we) os = Ht WHY eS 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 223 one mile in diameter surrounded by steep and lofty cliffs on every side, save one, where the sea enters by a single passage nearly dry at low water. In the interior of the small circular bay or crater there Fig. 9. Side view of the Island of St. Paul (N.E. side). Nine-pin rocks two miles distant. Captain Blackwood, R.N. slopes away in every direction from the crest of rocks encircling this erater. The highest peak is 820 feet above the level of the sea. If we suppose considerable oscillations of level to occur by gradual move- ments of upheaval and subsidence, the sea which has had power to wear away part of the island and produce lofty and perpendicular cliffs, would continue to keep open the smgle entrance, and as it deep- ened it would also enter and undermine the walls of the crater, so as to widen itsarea. Although by this means what is now the central and higher portion of the island would be entirely destroyed, still high interior cliffs would be produced, and a section of part of the volcano, now submerged, would be laid open in the deep ravine excavated on the eastern or lower side of the island. On every other side the rim of the enlarged crater or caldera might remain unbroken. SOMMA. The evidence of Somma having been originally a submarine volcano, has appeared more and more satisfactory in proportion as recent ob- servations have been multiplied. MM. von Buch and Dufresnoy affirm that the tuff which surrounds the mountain to the height of 1900 feet above the sea, contains marme shells analogous to those which I found at the height of 2605 feet on the neighbouring volcanic island of Ischia, all of which, except one, were of species now living in the Mediterranean. As some of the component beds of lava preserve throughout large spaces a uniform texture and are inclined at an angle of 30°, it is inferred by MM. von Buch, De Beaumont, and Dufresnoy, and probably with good reason, that they have now a much steeper slope than they had originally. On such a slope, they observe, such wide and compact sheets of lava could never have been formed. If, instead of imagining the superimposed tuffs and lavas to have swelled up like a great bubble according to the elevation-crater hypothesis, we suppose that they gained their additional steepness when they were traversed at successive periods by the dikes and veins with which they are now reticulated, we may account for the high angle of their dip, while at the same time the multitude of dikes, so far exceeding those seen at any other neighbourimg pot of the Phlegreean fields, points to this spot as the grand focus of eruption im ancient as well VOL. VI.—PART I, s 224 PROCEEDINGS OF THE GEOLOGICAL society. [Dec. 19, asin modern times. It explains, in short, why Somma, like Vesuvius, towers above all the other volcanic eminences. The summit of the submarine dome may probably have had a gentle slope on all sides, not exceeding perhaps 8° or 10°, although we have yet to learn in regard to subaqueous lavas, whether, moving through a denser and more resisting medium than the atmosphere, they may not spread in wider sheets and assume a compact texture, or an inclination exceeding that required to produce the same effects when their course is subaérial. The more general absence of ravines and valleys in the bed of the sea, where volcanic eruptions occur, would promote the spreading out of the melted matter in an even sheet, and the pressure of the incumbent water would check the expansion of the gases and prevent the mass from acquiring a more open and cel- lular texture. When M. Pilla had attentively observed in 1837 and afterwards in 1845 the similarity of the disposition of the beds in Somma and the modern Vesuvius, he could not resist the conclusion that both were formed in an analogous manner, and he rejected the theory of elevation-craters as applied whether to the one or the other*. Ata later period however M. Pilla admitted, that a sheet of basalt 1000 metres above the sea in Somma, inclined at an angle of 24° and very compact, proved that there had been an upheaval of the masst; an opinion which is compatible with the views embraced in this paper respecting the gradual increase of a cone by internal and external additions. That a vast number of eruptions were concen- trated within a narrow space is assumed by M. Dufresnoy himself, who considers the dikes of Somma as having been the feeders of successive beds or sheets of lava. It was not overlooked that a long series of eruptions occurring within very confined limits must in the course of time have given rise to a conical mass composed in this instance of superimposed fragmentary and porphyritic beds. Such a result how- ever was opposed to Von Buch’s hypothesis, and in order to escape from it in this and other analogous cases, a very arbitrary hypothesis was resorted to ;—a depression in the bed of the sea was assumed to have pre-existed, in which the beds of lava and scoriz accumulated in horizontal masses, and the position of the mass thus formed was finally inverted, the convex side being made to project upwards in- stead of downwards. Somma is the remains of a crater about three miles in diameter, the walls of which we may infer, from a passage in Plutarch, were before the great eruption of Vesuvius in the year 79, very perfect and entire, except on one side, where there was a single breach. Dr. Daubeny has shown in his comments on the passage, that when Spartacus encamped his gladiators in the crater in the year 72, Clodius the Preetor besieged him there, and keeping this smgle entrance carefully guarded, let down his soldiers by scaling ladders over the steep precipices which sur- rounded the cavity, now called the Atrio del Cavallo, where the insur- gents were encamped{. Originally therefore Somma had the usual form of craters of denudation, a single ravine interrupting the circuit” * Pilla, cited by Archiac, Hist. des Progrés de la Géol. tom. i. p. 538. + Archiae, ibid. p. 518. ~ See Daubeny’s Volcanos, p. 216. 1849. ] LYELL ON THE STRUCTURE OF VOLCANOS. 220 of the walls, and the fossa grande was perhaps a continuation of this ravine, and was hollowed out by the sea as the mountain was slowly raised above its level; but to what extent in this instance an original crater of eruption may have been widened by the sea, I will not ven- ture to speculate. Monte Nuovo. MM. von Buch and Dufresnoy regard this cone and crater as con- sisting of solid beds of white tuff previously horizontal, which were suddenly upheaved in 1538, so as to dip away in all directions from the centre with the same inclination as the sloping surface of the cone itself. 'To me it appears, that in addition to all the arguments derived from the absence of rents in the walls and rim of the crater, and the uniformity of structure of the whole funnel-shaped cavity from top to bottom, we have direct historical testimony against such an hypothesis. The cone is 440 English feet high and a mile and a half in circumference, the crater within a few feet as deep as the cone is high. The dip of the beds, from 18° to 20°, is not so great as that which Mr. Darwin observed in the beds of several craters of eruption in the Galapagos Islands, where the tuffs or mud-streams are inclined at angles of from 20° to 30°*. We have four descriptions given us by eye-witnesses, of the origin of Monte Nuovo, and there is I think no real discrepancy between them. Two of these narratives, viz. those of Faleoni and Pietro di Toledo, are cited by Sir Wiliam Hamilton ; another is that of Francesco del Nero, recently published (1846) in the ‘ Neues Jahrbuch,’ and translated in the Quarterly Journal of the Geological Society for 1847, while a fourth is that officially drawn up by the physician Porzio at the request of the Viceroy of Naples. Francesco del Nero mentions the drying up of the sea near Puzzuoli, and how the soil where the present volcanic orifice exists sank down about forty feet in the morning, and then about midday began to rise up again, so that, where it had subsided four hours before, it was ele- vated into a hill from which fire issued, and where subsequently a great abyss was formed. Such was the violence, the noise and the glare of light, that this eye-witness who was in his garden was much terrified. Many stones and much earth were cast out by the subterranean fire, so that they accumulated round the opening in great quantity. He then describes the shape of the hill, and finishes by referring to Por- zi0. Pietro Giacomo di Toledo, after mentioning previous earth- quakes and a slight general rise and drying up of the bed of the sea near the coast, says that at last, on the 29th Sept. 1838, the earth opened near Lake Avernus, and a horrid mouth was seen from which were vomited furiously and with a noise like thunder, fire, stones, and mud composed of ashes. Some of the stones were larger than an ox. 'The stones went as high as a cross-bow can carry, and then fell down, sometimes on the edge and sometimes into the mouth itself. The mud was of the colour of ashes and at first very liquid, then by degrees less so, and in such quantities that in less than twelve hours * Volcanic Islands, p. 107. s 2 226 PROCEEDINGS OF THE GEOLOGICAL socieTy. [Dec. 19, with the help of the above-mentioned stones a mountain was raised. When on the third day the eruption had ceased for a time, people looked down into the crater and saw the stones boilmg up in the middle. The day after, or fourth day, the crater began to throw up again, and on the seventh much more, and some persons were knocked down by the stones and killed. Falconi’s account also alludes to the earthquake and the bursting open of the earth, and how ashes and pumice-stones mixed with water were thrown up, and how the sea retired*. Porzio says, that a large tract of land between Monte Barbaro and the sea near Lake Avernus, was seen to raise itself and of a sudden to assume the form of a growing hill, and in the night this heap of earth (terre cumulus), as if opening its mouth, vomited forth a quantity of fire, pumice-stones, and ashes. On comparing all these contemporary statements, I infer that when the ground had first sunk down on the site of the future hill, the lava gradually propelled it upwards again, so that it was distended till it burst. The force of the escaping gases then hurled mto the air large fragments of the soil, mixed with mud and pumice, part of which fell back into the boiling gulf, while a part fell over the edge of the crater and contributed to the building up of the cone. We can scarcely expect to find in the walls of such a crater, any consider- able remains of the beds of tuff, which after subsiding and being again elevated must have been much shattered and torn to pieces by the elastic vapours and incandescent lava shot through them. All the descriptions would lead us to refer the great mass of the hill to the ejected mud and stones, accumulated in the course of a week by the intermittent volcanic action, and I can discover nothing implying such an upheaval of previously solidified and horizontal beds of tuff, as might lead us to expect that the walls of the crater would be found to consist of that more ancient formation. Von Buch indeed is said to have found some marine shells of existing Mediterranean species, like those which occur in the tuff of Campania, in some of the beds now exposed on the edges of the crater. Such shells may have been ejected in the mud mixed with sea-water which was cast out of the boiling gulf. If however they occur near the bottom of the funnel- shaped hollow, it is possible that some fragments of the original strata which were raised and burst through by the lava and gases may re- main, or some of the huge fragments cast up mto the air may well be discoverable in such a position. Since writing the above I have received a memoir on the volcanic region of Campania by Signor Arcangelo Scacchi, published in the Memoirs of the Royal Academy of Naples for 1849, in which he entirely concurs with me in rejecting the theory of upheaval for As- troni, Monte Nuovo, and other cones of that district. The position of the trachyte of the Solfatara and of Astroni are shown to be dif- ferent from what they would have been had the protrusion of the tra- chytic masses been the upheaving cause. In regard to Monte Nuovo, Scacchi remarks, that Porzio’s account * Campi Phlegrei, pp. 70, 77. 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 227 upon the whole corroborates the doctrine of its having been formed by eruption, in proof of which the following passage is cited from Por- zio’s description of the event: ‘“‘ Verum quod omnem superat admi- rationem, mons circum eam voraginem ex pumicibus et cinere plus- quam mille passuum altitudime una nocte congestus aspicitur.”’ Sig- nor Scacchi also adds, that the ancient temple of Apollo, which is now at the foot of Monte Nuovo, and the walls of which still retain their perfect perpendicularity, could not possibly have maintained that po- sition had the cone of Monte Nuovo really been formed by upheaval. Speaking of the fossil marine shells found in the tuff of Monte Nuovo, the same geologist observes, that as the tuff of the new vol- cano was formed in great part out of fragments of the ancient marine, shell-bearing tuff, the appearance of such fossils is easily explained. In one part of the circuit of Astroni he alludes to beds of ejected materials which for a short space are inclined at an angle of 40°, and which he therefore imagines may have been partially dislocated, although the materials of the rest of the same cone remain in their original position. Here I may poimt to the fact mentioned by Mr. Dana in his account of the Sandwich Islands, that strata of ejected substances have sometimes an original inclination of 40° in the “ cin- der cones,” although in the ‘‘tufa cones” formed near the sea, the slope of the beds does not exceed an angle of 30°. Erna. The great valley on the east side of Ktna, called the Val del Bove, which forms a grand amphitheatre between four and five miles in dia- meter, is surrounded for more than three parts of its circuit by nearly vertical precipices which vary from 1000 to nearly 3000 feet in height. As this hollow is not in the centre but on the flanks of a great coni- cal mountain, the precipices at the upper end of the valley are the loftiest, and they diminish gradually in height towards the lower side. The original form of the lower boundary of this enormous cavity is somewhat obscured by deluges of modern lava which have passed over it ; but there can be scarcely a doubt, that were these re- moved, the nearly circular escarpment surrounding the vast cavity would be complete, although of slight elevation on the lower or east- ern side where the lavas have poured over the edge of the rampart, seeming to have scaled it, just as they passed over the walls of Cata- nia in 1669. There seems however to have been always one point, where there was a breach in the boundary cliffs of the Val del Bove. This was situated at the south-eastern end of the valley and is called the Valley of Calanna, a narrow ravine, on one side of which perpen- dicular precipices 400 and 500 feet high display a succession of vol- canic strata intersected by a few dikes. The Valle di San Giacomo is the continuation of the Val di Calanna, and I conceive them to stand in the same relation to the Val del Bove, which the fossa grande probably held to the Atrio del Cavallo, or which the Baranco de las angustias holds to the caldera of Palma. After my visit to Etna in 1828, I suggested that the Val del Bove may have been produced by engulfment, an opinion which M. de 228 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [| Dec. 19, Beaumont has adopted ; and he has well remarked that it could not be attributed to explosions, for in that case vast showers of ejected matter comprising the former contents of the deep gulf or valley would have been apparent on the flanks of Etna. Without denying that some part of the missing rocks may be referable to engulfment, IT am now disposed to suspect that their removal may have been chiefly due to the denuding action of the sea, which probably availed itself of a breach in some lateral crater, or perhaps some partial sub- sidence, to gain access to and scoop out a circular bay, and carry out- wards in the course of ages the debris of the undermined rocks. On consulting my notes made in 1828, I find that this was my first 1m- pression on entering the great valley ; but the extent of surface covered by modern lava-streams, under which the bottom of the Val del Bove, as well as the north side of the Val di Calanna are buried, con- ceals so much of the ground, as to render it difficult and somewhat dangerous to speculate on the origin of the vast hollow. I may how- ever remark, in reference to aqueous action, that although no signs have been discovered of marine shells in any beds of fragmentary matter, composing the cliffs which bound the Val del Bove, yet ma- rine organic remains have been traced to the height of 800 feet above the sea near Trezza. Nor can there be a reasonable doubt, that if the lower parts of the great mountain were not covered with modern lava and ashes, similar proofs of the former presence of the sea would be discoverable at much greater heights. We might mdeed expect to find them at a higher elevation than any of the marine tertiary strata in Sicily, and these occur in the centre of the island as high as 3000 feet above the sea. If in the vicinity of Vesuvius beds contain- ing marine shells of recent Mediterranean species have been upraised to heights of between 2000 and 3000 feet, we are prepared to sup- pose that the uplifting force may have been developed with equal, if not greater intensity on the site of Etna, although no sections can be obtained in consequence of the enormous outpourings of lava and showers of scorize by which the older portions of the mountain are masked. The marine strata, containing shells of recent species, which crop out along the eastern and southern base of Etna, consist in great part of volcanic materials, of tuff, scoriz, and: ashes washed down into the sea, and of rolled pebbles of lava, as at La Motta near Catania, such as the destruction of the ancient denuded parts of a great cone may have furnished. The origin of some‘ of these may have been contem- poraneous with the excavation of the Val del Bove when the cliffs encircling that valley were washed by the waves of the sea. In reference to the question of denudation, I may ask those who have visited and may revisit Etna to consider whether the rocks called Musarra and Capra, which appear to be outstanding masses of ancient lavas intersected by dikes, rismg up near the middle of the Val del Bove, are not best explained by supposing them to be remnants of the once continuous cone not entirely carried away by the waves and cur- rents; also, whether the ridges of very ancient and crystalline volca- nic rocks called Rocca Giannicola and Rocea del Solfizio, which stand 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 229 out in relief from the cliffs at the head of the great valley, have not owed their preservation to their superior hardness, and consequent power of resisting aqueous action. There are in the tertiary lime- stones of the Val di Noto, in Sicily, circular valleys where the steep boundary cliffs have been shaped out into a great succession of ledges, separated by small cliffs, often producing an effect which I have compared (see ‘Principles,’ 1st edit. 1833, p. 110, vol. 11.) to the seats of a Roman amphitheatre. The precipitous rocks of white limestone thus carved out are sometimes 500 feet high. The period of this extensive denudation was very modern, geologically speaking, and we may infer that when the sea had power to shape out such cavities in rocks of uniform solidity and compactness, it may have exerted a far greater denuding energy on such alternations of stony and incoherent materials, as those now constituting the boundaries of the Val del Bove. The dimensions of Etna are on a sufficient scale to have produced a large crater of denudation, had a cavity been excavated in the sum- mit or centre, instead of on the flanks of the cone. Suppose the vol- canic mass not to have been cut away to a greater distance from the axis of the mountain than the middle of the Val del Bove ; there might have been a cavity formed three or four miles in diameter, encircled by escarpments from 3000 to 4000 feet im height. The dikes in that case would have been most numerous in the vicinity of the original and principal centre of eruption. At the nearest point to this centre now accessible is a rock already alluded to, called Giannicola, agreeing in mineral composition with the lavas of Etna, but highly crystalline, and massive, which Hoffmann describes as almost resembling gra- nite in structure, and between 150 and 200 feet wide. The deeper, therefore, we are enabled to see into the composition of the volcano near its central axis of eruption, the more massive and crystalline are the contents of upfilled fissures. I have offered in the ‘Principles of Geology’ an explanation of the fact on which M. de Beaumont has dwelt with much emphasis, that the more ancient parts of Etna have in the course of the last 2000 or 3000 years scarcely received any superficial accessions of lava and scorize (see ‘ Principles,’ 7th edit. p. 398, 1847). The dome-shaped or conical mass was probably several thousand feet less elevated when it was originally formed. After its bodily up- heaval the eruptions would become more and more lateral and basal, or in other words, the exogenous growth of the cone would shift its chief place of development. Yet the focus of eruption continued in the loftiest part of the cone where the lava still rises to a great height, and often overflows, whenever lateral eruptions occur. Mr. Hopkins has suggested, that if the denudation of the Wealden was anterior in great part to its elevation, the removal of an incumbent weight of matter from the central area might have enabled the expan- sive force to act with greater intensity on that space where so much less pressure remained to be overcome. In accordance with this view, we might expect that the Val del Bove, after the abstraction of volcanic masses varying in thickness from 500 to 4000 feet, would have become 230 PROCEEDINGS OF THE GEOLOGICAL sociETy. _[ Dec. 19, the almost exclusive theatre of eruptions. If such has not been the case, it is doubtless because the permanence of the site of habitual volcanic vents depends on deep-seated chasms and fissures in the earth’s crust extending downwards many leagues, and which cannot be affected by changes of a comparatively superficial nature. It is the opimion of M. de Beaumont, that the sheets of compact lava and alternating beds of scorize, which are now inclined in some of the cliffs encircling the Val del Bove at angles of 20°and 27°, were originally so horizontal that the lava emitted from different vents on the platform where they accumulated, flowed with equal freedom in every direction. To this circumstance he attributes the parallelism throughout a wide area, and the compact nature of a vast series of sheets of lava separated by more than 100 intercalated beds of pulverulent matter, cmders and angular fragments, such as are commonly cast out of craters during eruptions. The most cogent argument relied upon to compel us to embrace this view of original horizontality, is derived from the alleged fact that many of the dikes, intersecting the perpendicular cliffs alluded to, terminate upwards at different heights, and on reaching particular sheets of lava are there seen to blend, or ‘articulate’? with them. The dikes are therefore imagined to have been feeders, or the channels by which the lava rose up from below. The argument is ingeniously put in these terms. ‘‘ Had the fluid matter been poured out on an inclined plane, the bed when consoli- dated would have formed an elbow with the dike like the upper bar of the letter F, instead of extending itself on both sides like that of a T (Mém. pour servir, vol. iv. p. 149), and, moreover, the series of sheets of lava would have been more numerous in parts of the mountain farthest from the axis, for all the dikes which were feeders or sources of lava would have poured their contents down the sloping cone and never upwards.’ Although the rectangular junctions here alluded to escaped my observation in 1828, and I have not revisited Etna since M. de Beaumont wrote his account of them, I shall take the liberty of offermg a few comments on his statement of facts and method of interpreting them, as they appear to me so extraordinary that I feel at least entitled to demand, that the writer should acknowledge some difficulties in which his theory would involve us. In the first place I would ask, whence came the intercalated, inccherent and frag- mentary beds? M. de Beaumont can hardly escape the inference, that they have been emitted from the same orifices as the dikes, if these last were really the feeders of sheets of lava flowing out into the atmosphere. But if the lapilli and scorize were cast out at the same points of eruption as the lavas, how could they possibly be of the same thickness near the vents and at a distance from them? If an even plam had existed at the commencement of these fissure erup- tions, it would soon have acquired an irregular surface, for larger heaps of scorize would have been heaped up near the edges of the supposed linear vents, than at greater distances from them. I may also observe, that if vertical fissures gave vent originally at their upper extremities to horizontal sheets of lava so as to form dikes, joming at a right angle with the incumbent beds of lava, these dikes (fig. 10. a, 6, e) 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 231 would be thrown as much out of the perpendicular as the beds they intersect, when the latter were tilted by subsequent movements. The dikes therefore which have been feeders ought to slope at angles of Fig. 10.—Volcanie Dikes. My YY ij me Tp Hy Wh dL Y Uy, y Ui Mii between 23° and 27° to the horizon, whereas in the drawing which I made of cliffs in the Val del Bove, I have represented them as nearly all perpendicular. Had I seen a dike appearing to blend upwards with a sheet of lava, I should not have inferred any actual connection, unless I could have scaled the cliff, which is unfortunately inaccessible, and, hammer in hand, tested every inch of the junction. But had I thus assured myself of the fact, I should have first inquired whether the dike may not have sent off ves or branches which had penetrated between pre-existing parallel strata. If, however, I abandoned this idea as improbable because a sudden change of direction at right angles could scarcely occur or very rarely in such intrusive veins, I should have speculated on the possibility of such dikes having been filled partly from below and partly from above. After violent eruptions, the flanks of Etna have been fissured, and a bright light emitted from the rents has shown that there was incandescent lava below, although it has sometimes never reached the surface. It is conceivable, therefore, that lava-currents, descending from the higher and more central parts of the cone, might in their way fill up some rents of this kind, the tops of which are often left gaping after eruptions. Such a conjecture would at least relieve me from the extreme embarrassment in which I am placed by M. de Beaumont’s hypothesis, for | am not called upon in that case to regard the dikes as the feeders of a series of uniform and parallel beds of lava, with their accompanying strata of intervening lapilli and scoriz. The whole might then be imagined to have been poured out or projected from a permanent and powerful central vent, the eruptions being on a grand. scale, so as to allow of a considerable degree of uniformity in the spreading of the materials over wide areas, on the sloping side of a great cone inclined at angles between 4 and 10 degrees. A steeper inclination may have been afterwards acquired during the distension and injection of the mountain mass. 232 PROCEEDINGS OF THE GEOLOGICAL SociETY. [Dec. 19, We may naturally ask whether M. de Beaumont’s notion of the existence of such linear vents as the dikes above alluded to, is borne out by the analogy of the phenomena of other active voleanos. Mr. Darwin tells me that in St. Jago he saw horizontal sections of the bases of small craters, and the mass of rock which had formed the source or feeder was of a circular, not a linear form. He has also given us the section of a cone of eruption in the Galapagos (Volcanic Islands, p. 109), where we have a most perfect natural dissection of a crater. In that case we see a series of inclined parallel beds of ba- salt, separated by beds of loose, fragmentary scoriz, all parallel, and very uniform. Three of the sheets of lava unite with an irregular mass or column of the same substance, which was evidently the axis of the crater. The other streams of lava were no doubt, says Mr. Darwin, originally united to the same column, before it was worn down by the sea. Such a junction bears no resemblance to the dikes in the Val del Bove, because the lava has risen up a circular crater, and not by a linear fissure, and a cone has been formed ; whereas it is precisely the absence of such small cones connected with dikes on Etna, which presents the difficulty to which I now allude. Since the above remarks were written, I have perused Mr. Dana’s valuable work, on the Geology of the United States’ Exploring Expe- dition, published in 1849, and which reached London after this paper was drawn up. His observations on the great volcanos of the Sand- wich Islands tend greatly to confirm my views, in regard to the forma- tion of large flattened domes of volcanic matter poured out from a central vent, and they show that wide and extensive sheets of compact basalt and greystone have been formed on slopes considerably exceed- ing those which M. de Beaumont thought possible. In two of the principal volcanos of Owyhee, for example, Mounts Loa and Kea, we Pies tt. Mount Loa, in the Sandwich Islands. (Dana.) a a. Crater at the summit. 6. Crater of Kilanea. have examples of huge flattened volcanic cones 15,000 feet high (see fig. 11), each equaling two and a half Etnas in their dimensions, from the summits of which, and from vents not far below the summit, suc- cessive streams of lava, two miles or more in width, and sometimes twenty-six miles long, have been evolved. They have been poured one after the other in every direction from the apex of the cone, down slopes varying on an average from 4° to 8°, but in some places consi- derably exceeding that inclination. Mr. Dana, indeed, convinced him- self from actual observation, that, owing to the suddenness with which the lava cools, it may occasionally form on slopes equaling 25°, and still preserve considerable solidity ; nay, it is even, he says, possible, from what he saw in the great lateral crater of Kilanea (fig. 11 4), 1849. | LYELL ON THE STRUCTURE OF VOLCANOS. 233 that a mass of such melted rock may consolidate on a slope of no less than 50° or even 60°, and be continuous for 300 or 400 feet. ‘Such masses are narrow,” he adds, ‘‘ but if the source had been more gene- rous, it is not difficult to see that they would have acquired a greater breadth, and by a succession of ejections upon each cooled layer, even a considerable thickness might have been attained*.”’ The same author has also shown, that in the cinder-cones of the Sandwich Islands the strata have an original inclination of between 35° and 40°-+, while in the tufa-cones formed near the sea, they have a slope of about 30°. No one who reads the work alluded to will be of opinion, that the laws governing the formation and consolidation of sheets of basaltic or other kinds of lava have as yet been fully ascertained, or that the original inclination which they may have when flowing down the flanks of a volcanic mountain has been definitively determimed by the emi- nent French geologist who has collected together so much valuable information on the subject. There is another class of facts, however, brought to light by Mr. Dana’s investigations, which bear directly on the rectangular junctions of dikes and streams of lava to which I have called attention in refer- ence to the Val del Bove. He has shown, that, while copious streams of lava have been recently known to pour out from Mounts Loa and Kea from openings 13,000 feet above the level of the sea, there have been other contemporaneous fissures, produced at various elevations on the flanks of the same dome, out of which lava has streamed, unaccom- panied by the ejection of any scorize. It appears that the lava is so liquid, that the entangled gases escape very freely from it, without casting up to great heights in the air liquid jets of the molten rock, to which volcanic dust and cinders owe their origin. Now as these rents are described as running in various directions, it is quite clear that currents of lava descending from higher points must, as often as they pass over them, give rise to junctions resembling those in the Val del Bove, though not strictly at right angles. Still it is quite necessary in the case of Etna, where we have to account for enormous masses of interpolated scorize, and where there has been so much viscidity in the lava, to derive the beds of fragmentary matter, as I before sug- gested, from a higher and more powerful and permanent central vent, for they could never have proceeded from the lateral openings or dikes without disturbing that uniformity and parallelism of the strata, on the existence of which M. de Beaumont has so emphatically insisted. It is not a little satisfactory to me to discover that Mr. Dana, with whose opinions I was previously unacquainted, has been led by his extensive examination of the volcanos of the Pacific Islands to reject Von Buch’s theory of elevation-craters, although he has not alluded to the denu- ding action of the sea as affording an explanation of the large dimen- sions of many of the so-called cavities, such as Santorin, and the others on which I have dwelt in the preceding pages. * Dana, Geol. of Amer. Explor. Exped. p. 359, note. { Ibid. p. 354. 234 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Dec.19. Monts Dor anp CAnrTAL. That the name of craters of elevation should have been given to large conical masses, in no part of which can any crater be discovered, whether of denudation, or engulfment, or eruption, is a singular in- stance of theoretical language, mvented originally for distinct phe- nomena, becoming applied to another set of conditions, which are only in a small degree analogous. Although no craters are now discern- ible on the summits of Mont Dor and the Cantal in Central France, it is probable that they once possessed them, as I believe the greatest number of eruptions to have proceeded from the highest part of each mountain, where there is the greatest thickness of erupted lava and ejected matter. At this central point and around it, where so large a volume of basalt, trachyte, pumice, scorize, and other materials, whether solid or fragmentary, were emitted, the chief upheaval also may doubtless have occurred, and the slope of the conical mass may perhaps be greater now than it was originally. Yet as the average inclination of the dome-shaped mass of the Cantal is only 4°, and that of Mont Dor 8° 6’, we may reasonably question, after studying Mr. Dana’s description of the recent additions made to the flanks of Mounts Loa and Kea, the one having a slope of 6° 30', the other of 7° 46', whether there is any real necessity for supposing, that the basaltic currents of the French volcanos were at first more horizontal than they are now. The advocates of the elevation-crater theory, having assumed that the voleanic beds were in their origin almost horizontal, in Central France, found it indispensable to imagine, that a large cavity pre- existed in the granite, the lowest part of which comcided with what is now the highest part of the dome. At length, to use an expression of Ehrenberg in his paper on Volcanic Infusoria, ‘‘ the concave beds were converted into a convex dome,”’ and this as usual is referred toa paroxysmal effort of the subterranean force*. This subject has been so ably discussed, in the controversy between MM. de Beaumont and Dufresnoy on the one side, and MM. Constant Prevost and Virlet on the other, that I need say no more on the sub- ject. A closer observation of existing volcanos will decide whether the truth lies between the opinions of the opposite schools, and whether Messrs. Scrope, Constant Prevost, myself and others who have referred these mountains to successive eruptions proceeding chiefly from a cen- tral vent, have judged correctly, and how far we may have underrated the elevatory force, of which the intensity would no doubt be greatest at the point where the eruptive and injecting forces have been most energetic. That both the one and the other, however, have operated gradually, and with intermittent violence, not by any single great par- oxysm, I feel as convinced as ever. * Quart. Journ. Geol. Soc. vol. ii. p. 74, Memoirs. Jan.9,1850.| FLETCHER ON DUDLEY TRILOBITES. 235 JANUARY 9, 1850. The followmg communications were read :— 1. Observations on DupLEY TRitoBITES. By THomas WILLIAM Fuetrcuer, F.R.S., F.G.S., &e. Genus Licuas. Tue genus Lichas has received little attention from British paleeon- tologists, and even Burmeister was compelled to omit any notice of it from the want of characteristic specimens. In the hope of being enabled to contribute some materials towards a more perfect know- ledge of the genus, I am induced to offer to the Society a notice of several undescribed species which have recently been found im the Wenlock limestone of Dudley. 1. Licuas Bucxiano1, Milne-Edw., sp. Pu. XXVII. figs. 1-5 ; and Pu. XXVII. dis, figs. 1, la, & 16. Synonyms.—“ Trilobite de Dudley,” Al. Brongniart, 1822, Crust. Foss. pl. 4. f. 9. Peltura Bucklandi, Milne-Edw. Crust. v. i. 345. pl. 34. f. 12. Arges Anglicus, Beyrich, Untersuch. tber Tril. 2 St. t. 1. f. 3. This trilobite was first named by Prof. Milne-Edwards. Its ce- phalic shield is figured by Dr. Beyrich from a Dudley specimen. M. Brongniart, in his ‘ Histoire naturelle des Crustacés fossiles,’ had previously given, under the name of ‘a Trilobite from Dudley,” a figure of the under surface from a drawing by Mr. Stokes; merely remarking that the addition of spines to the tail, and the form of the cephalic shield, appeared to indicate a species differmg from Calymene Blumenbachi. The general form of the present species is oval and depressed ; its length is about an inch and a quarter, and its width three-quarters of an inch; the length of the thorax exceeds that of the cephalic shield and tail, which are about equal, the axis or middle division being narrower than the lateral portions. Large tubercles cover the ce- phalic shield, which is less than a semicircle, and is deeply indented at the sides by the production of the front. The glabella is large, broad, widest below, and divided into five tumid lobes; the forehead lobe is linear, and separated by deep curved sulcations from the short, ovate, upper lateral lobes, which are of about equal width with it; these are smaller than the lower lateral lobes, which project consider- ably below them. No basal lobes are visible in this species. The neck lobe is prominent and broadest in the middle, and the neck furrow distinct. Hyes forward, small, and prominent, placed beneath the la- teral indentation of the head, close to the lower lateral lobe of the gla- bella (PL. XX VII. dis, fig. | 6). Front margin narrow, the part above the indentation being angular. Facial suture running immediately beneath the front margin, and.curving downwards to the eye, parallel with the upper part of the glabella, below the eye curving outwards, 236 PROCEEDINGS OF THE GEOLOGICAL society. [Jan.9, and terminating on the posterior margin. Eyelid tubercular, len- tiferous surface smooth. Wings of moderate size, but not projecting forwards much beyond the eye; the posterior angles produced into rather short, broad spines. Hypostome almost equal in breadth to the upper part of the glabella above the lateral indentation, rounded at its insertion, and broadly truncate at its extremity. A strong concentric furrow separates the slightly convex anterior portion, which is deeply punctured, and a notch on each side divides it into two lobes, while sculptured lmes with a few puncta occur only on the broad outer margin. The thorax has eleven rings, the axis is moderately convex, and not so wide as the glabella ; it becomes gradually narrower towards its posterior part, and is divided by strong axal furrows from the pleurze, which are semicylindrical; they are bent backwards at about a third of their length; the terminations of the pleuree are separate, acute, and tubercular beneath. The tail is semi-oval with a spinous border ; its axis convex, not quite equal in width to its lateral parts, and extending two-thirds of the entire length of the tail; a narrow ridge from its apex connects it with the raised border of the tail; on its upper part are two distinct rings, and one or two more indistinctly marked. The lateral lobes are flattened. Two narrow and sharply raised ribs arching outwards and ornamented with tubercles are placed on the anterior portion of each side, and produced into short spines extending beyond the raised margin of the caudal shield; five similar spines occurring on the margin below make up the entire number of nine spines, one of which is terminal. The in- terstices between the ribs, as well as every other part of the animal, are covered with large and small tubercles. Variations.—One young specimen (fig. 3. Pl. XXVII.) has the margin immediately in front of the indentation with projecting angles almost produced into spines. The lower lateral lobes of fig. 1. Pl. XXVII. are narrower and less tumid than in most specimens, and the forehead lobe is wider in front than is usual. 2. L. wirsutus, n. sp. Pu. XXVIIL. figs. 6, 6 a, & 75eane Pi. XXVII. dis, figs. 2 & 2a. The body rings (Pl. XX VII. dcs, fig. 2) are much tuberculated, the axis tapering backwards, pleurze bent backwards, and slightly down- wards, the anterior ones at nearly half, and the posterior at about one- third of their length. Tail semi-oval, not mcluding the six strong spines. Axis subconical, extending about two-thirds of the tail, its width about equal to that of the lateral portions, with one strong ring upon the anterior portion and transverse rows of tubercles indicating the position of three or four indistinct rmgs. A narrow ridge extends from the apex of the axis to the bifurcate extremity. Two lateral ribs on each side, arched slightly outwards and sharply raised, are produced into thick tubercular spines extending beyond the raised margin. Interstices roughly granular with large tubercles ; small tubercles oc- curring between the large ones and appearing upon the spines of the border. From the great similarity in the arrangement of the tubercles upon 1850. | FLETCHER ON DUDLEY TRILOBITES. 237 the axis and sides, I am induced to regard Pl. XXVII. fig. 7, as the young of this species; the connecting ridge, however, is shorter in this specimen. The termination of the axis as represented in the figure is too obtuse. The young specimen last mentioned exhibits the incurved margin ; it is very convex and strongly marked with concentric lines, which also cross the spines. It has three lateral ribs on each side; but the middle rib probably represents the tubercular interstice of the older specimen. 3. L. Gravil, n. sp. Pr. XXVII. fig. 8; and Pl. XXVII. dvs, figs. 3, 3a, & 36. The outline of the cephalic shield is nearly semicircular, but slightly gibbous in front, and the surface granular, but not coarsely tubercu- lated. Glabella very large and regularly convex, as broad in front as behind. Forehead lobe continuous from the narrow front margin to the neck lobe, and narrowing posteriorly, but expanding suddenly at the base, where it has a slight prominence on each side. Its anterior part is wider and more convex than the upper lateral lobes, which it overhangs. Upper lateral lobes pointed, but rather obtusely below, and not extending to the neck furrow. Lower lateral lobes triangular in form, and smaller than the upper ; basal lobes small, narrow, ellip- tical, and placed widely apart; neck lobe broad, but not very promi- nent. All the furrows which divide the lobes of the head are shallow. Facial suture following the course of the anterior part of the glabella as far as the eye, its posterior course being unknown. Wing trian- gular and pointed, supporting the lunate eye upon a raised tubercular base ; surface covered with tubercles of unequal size, and the incurved front edge strongly and concentrically striated (Pl. XXVII. dis, figs. 3, 3a, 36). Kye moderate in size, and separated only by a slight furrow, not by any portion of the cheek, from the lower lateral lobe of the glabella. I have named this new species after my friend Mr. John Gray, of Dudley, whose fine collection is well known to all admirers of Silu- rian fossils. The head of this species has been figured in the ‘ Memoirs of the Geological Survey,’ vol. u. pt. 1. pl. 8, from a Malvern specimen, which was too imperfect to name. 4. L. Satreri,n.sp. Pu. XXVII. figs. 9 & 9a; and PL. XXVII. ‘bis, fig. 4. Glabella regularly convex, and broader in front than at the base ; forehead lobe linear, more convex than the upper lateral lobes, about equal to them in width, not expanded below, but extending to the neck lobe. Upper lateral lobes ovate in form, and pointed in their lower portion ; lower lateral lobes slightly tumid; cheeks (of which I find only a small portion supporting the eye) moderate in size, and separated from the glabella by a shallow groove. Eyes large and convex, the eyelid (rather exaggerated in fig. 9 a) nearly the size of 238 PROCEEDINGS OF THE GEOLOGICAL society. [Jan.9,— the lower lateral lobes ; it is placed very forward, and quite apart from the glabella. Large and small tubercles cover the whole surface, some of the former appearing almost spmous. The larger tubercles are symmetrically disposed, about four pairs being placed at regular intervals along the forehead lobe. This new species is named after my friend J. W. Salter, Esq., of the Geological Survey of Great Britain, in acknowledgement of his kind assistance in determining the species, and of much valuable in- formation received from him. 5. L. Barrannil, o.sp. Pu. XXVITI. fig. 10; and Pt. XXVII. dis, fis: 3: Strong tubercles of unequal size cover the whole surface of the tail, which is almost semicircular, its length being only two-thirds of its breadth ; the axis is wider than either of the side lobes,—it is sub- conical, and moderately convex in its upper part for rather more than half the length of the tail, then contracted suddenly to less than half — its former width, but does not taper to a point; it is depressed in its lower portion, so as to subside into the general surface of the tail considerably in advance of the bifurcate apex. The upper part of the axis is divided into three distinct rings, followed by a broad cen- tral tubercle. Each of the flattened sides of the tail consists of three foliaceous pleure or lobes terminating in broad projecting teeth, and separated from each other by narrow sharp furrows; each lobe is marked obliquely along its middle by a groove; the two upper lobes are directed outwards, their tips, projecting and acute, are recurved ; the third or posterior lobe is directed entirely backwards, and even inwards, to meet the corresponding lobe of the opposite side, from which it is separated by the broad terminal notch. The pleural grooves of the two upper lobes extend nearly to the tips, but run only a short distance in the posterior lobes. The incurved under portion is concentrically striated. This remarkable species has been named after my friend and correspondent M. Barrande, of Prague, whose forthcoming work on the ‘Systéme Silurien du centre de la Bohéme’ will doubtlessly en- hance a reputation already well established. L. Bucklandi is of more frequent occurrence than the other spe- cies, which are rare. EXPLANATION OF PLATE XXVII. Fig. 1. Lichas Bucklandi; a small specimen differing slightly from the usual form. Fig. la. Ditto, upper side, magnified. Fig. 1 6. Ditto, lower side, magnified. Fig. 2. The same species, of the ordinary form. Fig. 3. Lower side of a young specimen, with the front of the head very angular. Fig. 3a. Ditto, magnified. Fig. 4. Lower side of a full-grown specimen. Fig. 5. Tail of a young individual. Fig. 54. Ditto, magnified. Quart. Journ. Geol. Soc. Vol. VE. PL XXVIL.. ? OT Tet ; er geo WH Baily fecit. seem eS M.& N. Hanhbart bop. Tigs 1-5 Lichas Bucklandi,M.Edw> lid 6,7 Lhicsutus, Fletcher, M6 6.L.Grayit,Fletcher . Hid 9... Galteri, Fetch. Fio. 10. l. Bacrandn, Fletch. The figures marked+ are mapmbed 2% times Quart: Journ.Geol. Soc. Vol VI. PL, AXVIL das t s _— MAN Henbart Imp* +f oe | CR. Bone. Fiv.t, Lichas BucWendt._ Fiy. 2 __L. hirsutus._ Mg. 5. L. Gray. aig, L. Salterz._Fip 5, L. Barrandn._The fipures marked + are mapnified. a “ A 1850. | BRODIE ON THE INFERIOR OOLITE. 239 Fig. 6. L. hirsutus. Fig. 6a. Ditto, magnified. Fig. 7. Young specimen of L. hirsutus ? Fig. 7a. Ditto, magnified. Fig. 8. L. Grayit. Fig. 9. L. Salteri. Fig. 9a. Ditto, magnified: the eyelid on the right side is exaggerated in size. Fig. 10. Z. Barrandii: under surface of the tail, showing the incurved striated margin. Figs. 1, 4, 5, & 8 are from specimens in the cabinet of Mr. John Gray, to whose kindness I am indebted for the loan of them; the remainder are from my own collection. EXPLANATION OF PLATE XXVII. dis. Fig. 1. Lichas Bucklandi. A nearly perfect specimen; the first thorax-joint is lost,—its pesition is indicated in 1 a by dots. Fig. la. A highly magnified view of the same. Fig. 1 6. Outline, showing the eye and facial suture. Fig. 2. L. hirsutus; showing ten of the body rings and the tail. Fig. 2a. The tail magnified. Fig. 3. L. Grayii; one side of the glabella, with the lateral and basal lobes; the course of the facial suture posteriorly is indicated by dots. Fig. 3a. The same; the wing, with the eye. Fig. 3 6. Ditto, viewed from the front. Fig. 4. LZ. Salteri; a good specimen, showing the regular arrangement of the tu- bercles on the head. Fig. 5. ZL. Barrandii; a perfect tail. Figs. 1 6, 3, & 4 are from Mr. Gray’s collection; the rest are from my own. 2. On certain Beds in the INFERIOR OOLITE, near CHELTENHAM. By the Rev. P. B. Bropiz, M.A., F.G.8S. With Notes on a Section of LeckuHampton Hit. By H. E. Srricxyanp, Esq., MA., F.G.S. Tue inferior oolite in the immediate neighbourhood of Cheltenham, has been already well described in the ‘‘ Geology of Cheltenham,” by Sir R. Murchison, Mr. Buckman, and Mr. H. E. Strickland; but as there is a very interesting bed called ‘the roestone”’ by local geolo- gists, which, however, for obvious reasons it will be better to name * shelly freestone,’ containing several new and peculiar fossils, many of which have not been previously noticed, it may be desirable to lay a brief account of it before the Society. The outer escarpments of the Cotswold Hills are composed of the inferior oolite and lias, and form an important feature in the geology of the county, presenting bold headlands along the vales of Glouces- ter and Berkeley, in some instances rising to the height of more than 1000 feet above the level of the sea, and extending in a tor- tuous line for several miles from north-east to south-west. They constitute the eastern boundary of the Severn; the towns of Chel- tenham and Gloucester lying in bays at the foot of this range of hills, the base of which consists of lias, surmounted by a variable thickness of oolite. VOL. VI.—PART I, T 240 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 9, The followmg divisions (see Section, p. 242) of the oolitic strata at Leckhampton Hill, near Ohelteshata where the shelly freestone may be most advantageously studied, have been principally proposed and adopted by the authors of the work above reterred to; although. later investigations by Mr. Strickland prove, that their relative thick- ness is greater than has been generally supposed, and I have there- fore followed his admeasurements. The summit of the hill is capped by a rough, gritty stone, loaded with casts of Trigonia costata and T’. clavellata ; but neither this, nor the thin and very fossiliferous band of clay which separates it from the ‘ Gryphite grit,” are well developed in this section. Hence the latter (No. 2 of Section, p. 242) may here be more correctly said to be the first stratum m descend- ing order. It is a coarse calcareous grit, full of the Gryphea cym- éium and numerous other shells, the former of which is character- istic. The oolite marl*, or cream-coloured marly oolite, which suc- ceeds (No. 5 of Section, p. 242), is in places hard and concretionary, but often friable, and breaks up irregularly by the action of frost: it may be estimated at seventeen feet in thickness. It contains a large species of Natica, Plagiostoma, Arca, Rostellaria, and Terebratula fimbria; the last, which occurs in profusion, marks and is confined to this bed. It is locally rich in corals, one species occurring in large blocks exceeding two feet in length, and generally speaking, like the Pisolite, must have formed a coral-reef in the ancient ocean. It has also been subject to much denudation, not only when it first emerged from the waves, but probably at a later period ; for the corals and shells are frequently water-worn, and many of the former enter largely into the composition of the oolitic gravel which fills up hollows in the lias plain beneath. Towards the south this mar] is not so readily traced, until it appears again at Crickley and Birdlip, the top of the hill being composed of the great and more important underlying mass, which forms the thickest division of the inferior oolite, upwards of a hundred feet thick, and which is used for building and other purposes. It is ordinarily termed ‘‘freestone” (No. 6 of Section), and in part forms a fine-grained, light-coloured oolite, closely resembling the Bath freestone, and is nowhere absolutely destitute of organic re- mains, the harder stone being made up of comminuted fragments of shells and corals. The more perfect specimens are almost entirely confined to two or more shelly masses, one of which may be seen at the summit of the hill on the south, where it crops out, and has been broken up and water-worn. ‘There it becomes flaggy, and bears a striking mineralogical resemblance to certain beds in the Forest marble and Great oolite, and this is the prevailing character of these subor- dinate groups. One of these upper shelly layers may be traced from * The oolite marl reappears near Stroud, and, with very slight lithological va- riations, is similar to that at Leckhampton. It affords, like the latter, many shells peculiar to it, but they are more numerous and better preserved. Mr. Lycett’ s fine collection contains several species which have not yet been observed in the vicinity of Chelteniam. Viewed as a whole, the shells are remarkably distinct from all other beds in the great and inferior oolite.. Mr. Lycett possesses more than 130 species from this stratum. ° 1850. | BRODIE ON THE INFERIOR OOLITE. 24) north to south along the whole of the escarpment, and at one spot near the Devil’s Chimney, where the freestone is thickest, it shows itself about eighteen feet below the oolite marl, and is there a coarse crystalline rock, mainly composed of shells and corals, a foot and a half thick. The more interesting fossiliferous division of the free- stone immediately overlies the Pisolite (“ Pea-grit” of Murchison*), and attains a thickness of seventy-five feet. It is a coarser and softer oolite than the upper part of the freestone, of a yellowish-white colour, and abounding in a great variety of small shells and corals, many of which belong to new species, and which are strikingly con- trasted with those in the superior and inferior beds. Since the free- stone is traversed at irregular intervals by certain shelly layers, con- taining the same characteristic fossils, and the whole evidently forms one connected stratum, which has been exposed, apparently, to cur- rents of water of greater or less intensity, and the shells and corals in consequence more or less abraded, it will be better to adopt the term “shelly freestone+,”’ instead of “‘roestone,”’ which simply means oolite. As the Pisolite can be followed all along the line of the escarp- ment, the lower shelly beds in the freestone can be accurately defined ; but the upper fossiliferous strata, from the height of the cliff, are more difficult to distinguish. They may be best examined on the western brow of Leckhampton Hill, where the oolite marl above, and the Pi- solite below, form very good horizons for marking the course of the intervening freestone. On the north and south the freestone is much reduced in thickness, and at the more southern end of the hill the higher beds are not exposed ; but at the northern extremity, opposite Cheltenham, the upper series is largely developed. The general and true dip is at an angle of about seven degrees to the south-east. The freestone and associated deposits extend for several miles along the entire line of the Cotswolds, m the district now under review, where they present occasional lithological variations, but are in most cases equally rich in organic remains. On the whole, Leckhampton Hill affords a good type of the lower oolitic system constituting the outer edge of the Cotswold chain in its range from north-east to south-west across Gloucestershire, although there are, as may be ex- pected, certain local distinctions in the comparative thickness, mine- ralogical structure, and zoological contents of particular beds. The superior strata, however, above the Trigonia grit, are not exposed at Leckhampton, but occupy the higher grounds on the east, up to their junction with the Stonesfield slate. With the permission of my friend Mr. Strickland, I subjoin the following corrected section of Leckhampton Hill, from the Trigonia grit to the lias inclusive. * Geology of Cheltenham, 1834, p. 12. sections figs. 1 & 2. + The term ‘shelly freestone’”’ must be understood to apply to the lowest and more fossiliferous division of the freestone just above the Pisolite, and to the other shelly bands which are interspersed amongst it. The word “ freestone” has been already given by Sir R. Murchison to the upper part, and may therefore be used in contradistinction to the above, though in common parlance it may with pro- priety designate the entire sequence between the oolite marl and the Pisolite. T2 i t Leckhampton Church. 242 PROCEEDINGS OF THE GEOLOGICAL society. {[Jan. 9, Section of Leckhampton Hill, on the scale of 180 feet =% inch. | ee — j feet. in DD PRONG PTI < Cseencer ore qeeenarene pean ee aneaanoe eee eer pee 2 Geypaive eerie ST UAE ekadaw cso cewsutowsecdecenen ee 7 0 3. Rubbly oolite, with many fossils ...................cs00e 24 0 4, Fragmentary oolitic freestone, apparently unfossili- Ey ferous...... wessesteteee sees eteeeeeees cpetseseeesestenecnes 26 0 | Inf. Oolite, . Oolite marl with Terebratula fimbria .......21000 0.205. LW igi | 930 ft 6. Freestone, quarried for building, with shelly layers at ? irregular intervals, the thickest and more fossili- ferous portions at the base ............ 2... eee eee ee eee 106 6 7. Pisolite (“‘ Pea-grit’’) and ferruginous oolite (‘ Be- lemnite bed”) and Sand*¥ <2... ....ssc.ncnsensene 42 0) SB. “Upper ids, AUOUt co. a0. do cota ewonsean anew = seaccescetene 180 0 Le OlF Maristone, dhOut 2s Fe ees eae eee 50 0 749 Ht 10. Lower lias (probably 600 feet thick) .............0000. 519 0 F Total height above the Sea ...:.pesccc--sse- a NEEM s |) Seem sandy clay, much mixed with, green ————— EO oe sand, and passing downwards into a conglo- — —— == == =2 | 1. Tabular septaria, with numerous fossils. merate with round flint pebbles, and partly rounded pebbles of chalk and red clay. Con- tains afew Ditrupa plana. 3 to 4 feet. d. Mottled clays—dark red (upper part of). The occurrence of pebbles of the underlying mottled red clay in the lower part of the basement of the London clay “ce” is a fact here to be particularly noticed. The organic remains found in this bed are as under :— Cardium Plumsteadiense, Sow. Ostrea, a large undetermined species. Corbula, a finely striated species. Pectunculus brevirostris, Sow. Cytherea obliqua, Desh. Pyrula tricostata, Desh. Ditrupa plana, Sow. sp. Rostellaria Sowerbyi, Want. Natica glaueinoides, Sow. Teeth of Lamnert. Traces of carbonized vegetables and wood. Passing over to the northern part of the Hampshire tertiary di- strict, the only good section of this bed that I am acquainted with was exposed in a cutting on the Railway at Clarendon Hill, three miles E.S.E. of Salisbury. (See fig. 2.) * For an outline map of the tertiary strata, see Quart. Journ. Geol. Soc. vol. iii. pl. xiv. + I have omitted the name of the species, as I feel in doubt as to which of Agassiz’s species to refer it. It probably is the L. elegans, or there may be more than one species. The same species accompany this bed throughout its entire range. postions * —S The chalk crops out about 60 feet below ‘‘c.’’ - Stratum ‘‘c’”’ here contaims no organic remains, except the teeth of the same species of Lamne which occur at Clarendon Hill, and which we shall find to accompany this bed very constantly in the London district. This pomt forms the apex of a long and roughly triangular area, occupied by the tertiary eocene strata, and stretching eastward to the German Ocean. The southern side of this triangle extends from Pebble Hill to the cliff near the Reculvers in Kent, a distance of about 100 miles, and the northern side from Pebble Hill to Woodbridge in Suffolk, nearly 140 miles. Owing to the thickness of the London clay in the tract between these two lines, it is only by well-sections that we can learn anything of its basement bed. If however we follow the outcrop of the beds, we shall find this stratum coming to the surface with much regularity along the southern edge of the tertiary area, whilst along its northern edge it forms a more broken and irregular line. This arises from the tertiary deposits being, on the south from Inkpen to Croydon, tilted up at a considerable angle against the ridge of chalk hills, which throws them out sud- denly and sharply, whereas towards the north they rise gradually, and form with the chalk a tolerably regularly inclined plane from their outcrop from below the London clay to the edge of the chalk escarp- ment, disappearing only gradually according as the chalk attains a higher level, and adapting themselves to all the irregularities and variations of the surface. | On this latter side, therefore, the tertiary strata often form hills overlooking the chalk district, whilst on the south side the chalk hills almost constantly command fine and extensive views over the tertiary area. In following the basement bed of the London clay eastward from Pebble Hill, it will be convenient to take these two sides of the triangle separately. It happens that many of the beds between the chalk and the London clay are of considerable economical value for their sands, and tile and pottery clays, and they are consequently worked to a great extent. A zone of brick and tile fields in fact marks their outcrop from Marlborough to Ewell on the one side, and to Woodbridge on the other. We are thus furnished with a series of sections, such as we obtain in no other part of the English ter- 1850.| PRESTWICH ON THE LOWER TERTIARY STRATA. 299 tiaries. They enable us to trace the sands and mottled clays with- out much difficulty over a large district ; but although these lower tertiary beds are so frequently worked, and their relation to the chalk underlymg them is often shown, the sections nevertheless rarely exhibit the overlying lower beds of the London clay. At the base of the chalk hills between Inkpen and Basingstoke there are a considerable number of sections, more or less perfect, of these lower tertiary beds. One of the best and most illustrative is in a brick-field at Itchingswell, two miles westward of Kingsclere. (See fig. 4.) Fig. 4.—Section at Itchingswell. SANK < ~ SS 6. London clay ; upper part bluish grey passing down into brown; sandy at base; a few calca- reous concretions, and a few fossils. (The lower part of this bed should perhaps be in- cluded in ‘‘ @.’’) ce. Ferruginous sand and iron sandstone mixed with green sand, and full of round flint pebbles, varying in size from 1 to 14 inches in diameter; no fossils except a few teeth of Lamne. d. Mottled clay and sands. The chalk outcrops at a distance of about 50 feet from ‘‘ e.’’ at Itchingswell. be) Organic remains of stratum “ec, Cancellaria leviuscula, Desh. Nucula. Cytherea obliqua, Desh. Panopea intermedia, Sow. Ditrupa plana, Sow. sp. Pectunculus Plumsteadiensis, Sow. Ostrea, large species. These fossils occur at the base of ‘3,’ just above ‘‘c.”’ A section at Chinham, one mile and a half north-east of Basing- stoke, on the line of railway from that town to Reading, showed the basement conglomerate bed passing gradually upwards into the mass of the London clay. The organic remains were numerous, but in a very friable state. (See fig. 5.) Fig. 5.—Section at Chinham. London clay ; thin-bedded brown clay with- out fossils passing downwards into dirty yellow sands with seams of brown clay, and then into a sandy light-coloured clay ‘*¢,’? with seams of green sand and a few round flint pebbles occasionally concreted into small flat masses by carbonate of lime; traces of vegetable matter; shells abundant in the seams and patches of green sand, but very friable and generally in the state of casts. Average thickness of ‘‘c’’ 5 feet. d. Mottled red and brown clays ; upper surface slightly uneven and worn. The junction with the chalk, which crops out immediately on the opposite side of the small valley formed in these lower sands, is not exposed. Organic remains of stratum “ec,” at Chinham. Cassidaria striata, Sow. Fusus, small species. Cardium Plumsteadiense, Sow. Modiola elegans, Sow. Cytherea ovalis, var. ?, Sow. Natica glaucinoides, Sow. Ditrupa plana, Sow. sp. —— Hantoniensis, Pilh. 260 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 23, Ostrea, small species. Rostellaria ? Pectunculus Plumsteadiensis, Sow. Teeth of Lamne. Pyrula tricostata, Desh. Hence this bed may be traced by Old Basing, Odiham, Farnham*, to Guildford, where an interesting section of it was exposed on the lme of railroad a few hundred feet north of the present station. (See fig. 6.) Fig. 6.—Section at Guildford. N. ( Brown London clay without fos- sils, passing downwards into rellowish sand, and then into ‘*e,?? mixed yellow sand and clay and green sand; full of round flint pebbles, but without organic remains. . Yellow sandy clay full of shells, perfect and in fragments (Cy- rena, Cerithium, and Ostrea). 2. Very dark clay mottled red. 3. Light greenish clay mottled red, passing down into mottled clays of different colours and sands. The junction with the chalk is not exposed. The outcrop of this latter is however seen a few yards nearer Guildford. This section is of much interest from the circumstance of a thin layer (1 of d) of the fluviatile shells of the Woolwich beds occurring on the top of the mottled clays and under stratum “c.’’ This is the most westerly point at which these shells have, I believe, been yet observed. They consist of several species of Cyrena, Cerithium, and Ostrea. The line of separation between beds ‘‘c” and “‘d” is waved and irregular. Passing by Leatherhead, Epsom, and Ewell to Croydon, no good section of this bed is exhibited ; indications of it occur only here and there. It then trends suddenly to the north, but still it is not exposed until we reach Lewisham, where, in one of the pits near the summit of Loam-pit Hill, the London clay, with a thin basement conglo- merate bed, may be seen overlying a bed of light-coloured sand. (See figs 72) Fig. 7.—Section at Loam-pit Hill. SS = 2. Brown clay mixed with flint gravel. [= = 6. London clay; laminated brown clay with septaria oc- = casionally. No organic remains yet found. = > = = === ¢. Round flint pebbles in brown clay, and in places sand. No organic remains. =d. Light yellow and whitish sands. 8 to 10 feet exposed. The pits lower down the hill show in disconnected sections the * Two miles W.N.W. from this town J have recently found in a brook above Lower Old Park Farm, detached blocks with numerous fossils of this “‘ Basement bed.” 1850.| PRESTWICH ON THE LOWER TERTIARY STRATA. 261 series of the Woolwich fluviatile beds, and the underlying sands re- posing upon the chalk*. At Counter Hill, stratum ‘‘c”’ is two feet thick, and shows very distinctly the irregular and worn surface of ‘‘d,”’ on which it reposes ; «‘q”’ is there thinner, of a nearly pure white colour, and contains numerous small patches of small round flint pebbles. On the line of the Croydon Railway immediately south of the New Cross Station, is a section of this bed, which has already been described by Mr. Warburton in 1844+. For the sake however of showing its con- nexion with the foregoing details, I here give a diagram of that part of the cutting, showing the conglomerate bed at the base of the Lon- don clay. (See fig. 8.) Fig. 8.—Section at New Cross. Ser 5. London clay; tough brown clay with septaria, but without organic remains. ——————————__— = [remains. —- =e. Dark ochreous sand full of round flint pebbles. No organic ZZ Va. {ecllow sand and clays forming the upper part of the series == = of the Woolwich fiuviatile beds hereafter to be described. The chalk has been reached at a depth of about 100 feet beneath stratum “ec.” We must now make a slight deviation in order to examine a well- section at Hampstead, the particulars of which were communicated to the Geological Society in 1834 by Mr. Wetherellt. It was shown, that the London clay was there underlaid by a compact rock, five feet thick, formed of green sand, with numerous round flint pebbles, and cemented by carbonate of lime, reposing upon a series of sands and mottled clays overlying the chalk. The following are the organic remains he gives from this rock :— Rostellaria lucida, Sow. (? Sow- Pleurotoma. erbyi, Mant.) Venus incrassata, Desh. sp. (? Cytherea Natica glaucinoides, Sow. obliqua, Desh.) Nucula. Scales and teeth of fishes. Panopea intermedia, Sow. Lignite. Cardium nitens, Sow. We are now arrived at a point of considerable difficulty. So far the range of this stratum has been regular, and the line of demar- cation between it and the upper part of the mottled clays and sands has been well-marked ; but on reaching the neighbourhood of Croy- don and London a different order of thmgs commences. The mottled clays disappear except in small quantities, and in a few places; large and thick beds of round pebbles set im, interstra- tified with a peculiar series of fluviatile and freshwater beds. The London clay recedes further to the north, leaving a large and more * For a better section than any now exposed of these beds, see Dr. Buckland’s paper in the Trans. Geol. Soc. vol. iv. p. 285; also Phillips and Conybeare’s Out- lines of the Geology of England, p. 49. T Quarterly Journal of the Geological Society, vol. i.p.172. See also Phillips and Conybeare, Geology of England, p. 48. t Trans. Geol. Soc. 2nd Series, vol. v. p. 131. * 262 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 23, hilly district, stretching from Croydon to beyond Gravesend, occu- pied solely by this sandy and pebbly series reposing on a base of chalk, and only in a very few cases showing a capping of the London clay. The difficulty is, whether we are to consider any of the pecu- liar fossiliferous, sandy or conglomerate beds of Woolwich, Bromley, and adjacent districts as a fuller development of the basement stratum of the London clay, or whether they all belong to a distinct and underlying series. I am rather inclined, on structural evidence, to the latter opinion ; nevertheless, on paleeontological grounds it might be presumed that a passage here exists between the two series. We however yet feel the want of a few good sections to settle clearly this point, to which I shall have occasion to revert more fully in another part of this paper. : At various points beneath the outlier of London clay at Shooter’s Hill are indications of the basement pebbly bed of the London clay ; and some years since there seems to have been at Plumstead a deeper and better section than any now existing; for in some of the early numbers of the ‘ Mineral Conchology,’ Mr. Sowerby described a group of shells from this locality which bore a strong general resemblance to those of the bed we are describing. The following is a list of the shells he enumerates :— Cardium Plumsteadiense, Sow. Fusus labiatus, Sow. sp. Calyptrza trochiformis, Lamk. Melania inguinata, Defr. Cerithium variabile, Desh. Neritina uniplicata, Sow. Fusus latus, Sow. sp. Panopza intermedia, Sow. costatus, Sow. Pectunculus Plumsteadiensis, Sow. —— gradatus, Sow. sp. Planorbis (?) hemistoma, Sow. Mr. Morris informs me that he has here found casts apparently of the Cyprina Morrisii. From Mr. Sowerby’s description, I cannot learn whether the fos- sils were all found in the same bed; I should be inclined to believe that they were not. The Planorbis hemistoma, Neritina uniplicata, and some species of Fusus, I have never found associated with the Panopea intermedia and Cardium Plumsteadiense, so characteristic of the basement bed of the London clay. Still, if this bed was here accumulated under more fiuviatile conditions, there would be no valid objection to such an association of organic remains in this part of the series. About six miles to the north-west of this spot, a cutting on the Eastern Counties Railway, at Maryland Point, near Stratford-le-Bow, exposed a very illustrative section. (See fig. 9.) Fig. 9.—Sectzon near Stratford. E. Pe ree At «/.+421°a. Ochreous flint gravel. ee | AS Fa) ===. Brown clay (lower part of London clay ?). ee | 1. Clayey green sand. 2. Yellow and ochreous sand. 3. Yel- ce low and ochreous sand, with round flint pebbles and nu- merous fossils. It occasionally forms calcareous concreted masses. aS 2 ————————————— SSS 3 ' d. 1 to 3. Brown, dark grey and yellow clays. 4. Yellow sand —————— 4 | (5 feet), reposing upon a considerable thickness of mottled SSS SSS clays not exposed, 1850.| PRESTWICH ON THE LOWER TERTIARY STRATA. 263 Organic remains of stratum “ec,” at Maryland Point. Cardium Plumsteadiense, Sow. Pectunculus Plumsteadiensis, Sow. Cytherea obliqua, Desh. Pleurotoma, a small ribbed species. Calyptrea trochiformis, Lamk. Rostellaria Sowerbyi, Mant. Fusus. Tellina ? Melania inquinata, Defr. Scalaria. Natica glaucinoides, Sow. Teeth of Lamne. Ostrea Bellovacina, Lam. A boring Mollusk, probably a Litho- Pectunculus brevirostris, Sow. domus. It will be observed that this bed is here as well characterized as at Clarendon Hill or Chinham, and that, with the exception of a single specimen of the Melania inquinata, its fauna does not at all resemble that of the Woolwich fluviatile beds. This solitary specimen had also the appearance of having been rolled and worn. The low country along which this bed outcrops from Stratford to Horndon is covered with gravel and exhibits no sections. Some years since, however, a group of shells, similar to the above, was found at Stifford Bridge near Purfleet, and specimens of them are, I am in- formed by Mr. Morris, now in the Geological Museum at Cambridge. On the south side of the Thames, another outlier of the London clay exists, I believe, on the Swanscombe Hills near Greenhithe, but although I have examined them closely, I have not been able to meet with a section of the basement beds. We next arrive at the fine sections at Upnor on the banks of the Medway two miles north of Rochester. We there have nearly all the beds between the London clay and the chalk exposed in a few large sections. For the present it will be sufficient to exhibit the upper part of the section on the banks of the Medway, a short distance beyond the Castle*. (See fig. 10.) Fig. 10.—Section at Upnor. eS» —— 6. London clay ; upper part dark brown and very tenacious, pass- ing down into sandy lighter coloured beds. No organic re- mains have been yet found in it. | 1. Brown clay and ochreous sand, with traces of lignite. Gs ey 2. Light greenish sand, with a few patches of friable SRA 4 shells. 3. Fine yellow sand, with a few shells. 4. In- durated clay, with numerous shells and traces of plants. 5. Yellow sand, the upper part full of round flmt pebbles, and the lower part abounding in shells. Concreted masses, full of shells, not uncommon. SS 7d. 1. Light yellow and whitish sand; upper surface indented ——————— == by stratum ‘‘c;’’ contains a few shells (Ostrea and Cyrena) in irregular patches, and occasionally an un- derlayer of large Ostrez. 2. A series of dark tough clays, with subordinate lignite and beds full of the fluviatile shells of Woolwich. 3. Variable yellow sands, reaching probably to the chalk, at a depth of 50 or 60 feet below ce C22? * This section is described by Mr. Morris in the Proc. Geol. Soc. vol. i. p. 451. 264 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan..23, 33 Organic remains of stratum “c, at Upnor. Cardium nitens, Sow. Cytherea ovalis, var.?, Sow. Plumsteadiense ? Sow. Glycimeris or Panopea. Nn. Sp. @. Melania inguinata, Defr. Cytherea or Cyprina, large gibbous sp. Natica Hantoniensis? Pilk. Calyptrea trochiformis ? Lamk. Ostrea. Cerithium variabile, Desh. Pectunculus Plumsteadiensis, Sow. Cyrena cuneiformis, Sow. Pleurotoma. obovata, Sow. var. Rostellaria Sowerbyi, Mant. tellinella ?, Fer. Teeth of Lamne. The undoubted admixture at this spot of several species of estuary shells of the Woolwich beds with the ordinary fauna of stratum “‘e”’ is to be noticed. Thence through Sittingbourne to Faversham, I have met with no section of this bed. In the year 1841 Mr. Trimmer*® called attention to a fossiliferous sandstone overlying the lower sands which repose - on the chalk, on the hill above Boughton between Faversham and Canterbury, and mentions the occurrence there of four species of mollusks. I visited this locality with Mr. Rees in 1843, and we obtained from it a considerable number of other fossils, but owing to the state in which they are preserved, the following list must be received with some doubt. The bed consists of layers of very hard and compact siliceous sandstone with subordinate bands of iron sandstone. One of the upper seams of the latter contains rounded flint pebbles, and abounds with extremely well-marked impressions and casts of shells, but the substance of the shells is in all cases re- moved. The superposition of the bed is not shown. It is about five feet thick. At a short distance above it the London clay appears, and below it, in the valley, the chalk outcrops. 93 Organic remains of “ec,” near Boughton. Astarte. Fusus latus ? Sow. sp. Calyptrea trochiformis, Lamk. , long narrow species, same as at Cardium nitens, Sow. Upnor. Plumsteadiense, Sow. ——, nl. sp., same as the Hedgerley sp. , 1. Sp. &. Melania inquinata, Defr. Cerithium variabile, Desh. Natica glaucinoides, Sow. Cyrena cuneiformis, Sow. Panopea intermedia, Sow. obovata?, Sow. Pectunculus brevirostris, Sow. Corbula longirostris, Desh. Plumsteadiensis, Sow. Cytherea ovalis, var. ?, Sow. Pyrula ? Cytherea or Cyprina, a large gibbous sp. Rostellaria Sowerbyi, Mant. The estuary species of mollusks are here less numerous than at Upnor, and the marine species show an increase. This bed thence passes by the north of Canterbury to the cliffs be- tween Herne Bay and the Reculvers+, where a remarkably fine section of the lower part of the London clay and of a large portion of the underlying strata is exposed. These latter here put on a character very different to any we have hitherto observed. Both the fluviatile * Proc. Geol. Soc. vol. iii. p. 457. + See paper by Mr. W. Richardson, Proc. Geol. Soc. vol. ii. p. 78; also the paper before quoted of Mr. Morris. 1850.| PRESTWICH ON THE LOWER TERTIARY STRATA. 265 beds of Woolwich as well as the mottled clays are entirely wanting. Still the physical or paleontological characters are such as to warrant our considering as the basement bed of the London clay the twenty feet of sands immediately underlying the London clay, although there is here no passage between them. This bed is well exhibited in the centre of the cliff east and west of the ravine at Bishopstoke, two miles east of Herne Bay. (See fig. 11.) Fig. 11.—Section near Herne Bay. a. Brown and yellow clay, more or less mixed with ochreous flint gravel. 6. London clay; upper beds of a brown colour, and with a few small septaria covered with vermiform impressions, passing down into laminated dark grey clay, more or less sandy, with carbonized vegetable matter. Traces of Ditrupa plana and of two species of Nwmmulites occur in the lower part of this clay; other fossils are extremely scarce. fa. Thin irregular seam of green sand; ferruginous clay and afew round flint pebbles, 2 to 3 inches. 2. Very light yellow sands with tabular con. creted masses of sandstone and iron sandstone; -@ these are frequently overlaid by a mass corre- J sponding in size of dark clay; very friable shells are irregularly dispersed throughout this bed in small layers and in patches; on the under side of the blocks they are particularly abundant, casts chiefly. 3 & 4. Small flint pebbles with a very irregular series of thin beds of clay and of ferruginous sandstone full of casts of shells. Teeth, vertebree and bones of fishes of frequent occurrence. d, Light greenish clayey sands; upper surface worn and indented by the pebble bed above. Beneath are some very fossiliferous clayey sands. Organic remains of “c,” in the Herne Bay cliffs. Astarte. Natica glaucinoides, Sow. Buccinum junceum, Sow. Hantoniensis, P2k. Cardium nitens, Sow. Nucula margaritacea, var. 8, Desh. Plumsteadiense, Sow. , longer sp. , Nl. Sp. @. Ostrea, small sp. Cerithium variabile, Desh. Pectunculus brevirostris, Sow. Cytherea obliqua. Plumsteadiensis, Sow. ovalis, var.?, Sow. Pleurotoma comma, Sow. Cytherea or Cyprina, a large gibbous sp. , a second sp. Cyprina Morrisii, Sow. Pyrula. Corbula revoluta, Sow. Rostellaria Sowerbyi, Mant. Fusus tuberosus?, Sow. , nh. sp. large and striated. » 0. Sp. Scalaria. Modiola. Vertebre, bones and scales of fishes. Natica labellata, Lamk. Teeth of Lamne. The estuary species, it will here be observed, have almost entirely disappeared, and we have a fauna presenting a very close analogy with that of stratum ‘“c” at Sonning Hill near Reading and Claren- don Hill near Slaten: Still at Herne Bay, and more especially at Boughton and Upnor, the fauna differs in some measure from the one which I consider to be synchronous with it to the westward of London. The bed itself also appears more distinctly separable in mineral character from the London clay. We will now return to our starting-poimt at Pebble Hill, and thence 266 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. ([Jan. 23, follow the northern outcrop of this deposit to Woodbridge. ‘Taking a line by Newbury and then northward of Woolhampton to Reading, I know of but one tolerable section of this bed; it occurs in a brick- field on the summit of the hill at Englefield near Theale*. The London clay caps the hill to the depth of twenty to thirty feet. It is brown and sandy, and contains at its base a band of tabular septaria,— very ferruginous and containing a few rounded flint pebbles. These septaria are occasionally full of the casts of the following shells :— Cardium. Panopea intermedia, Sow. Calyptrza trochiformis, Lamk. Pectunculus Plumsteadiensis, Sow. Ditrupa plana, Sow. sp. Rostellaria Sowerbyi, Mant. Nucula ? Soft, brown wood in fragments. Natica. Teeth of Lamne. The sands and mottled clays outcrop immediately under these beds, and the chalk appears at the northern base of the hill. At Reading Mr. Rolfe has pointed out a thin stratum overlying the Plastic clay series, and containing the following organic remains f: Cytherea obliqua, Desh. Ditrupa plana, Sow. sp. Pectunculus brevirostris, Sow. Modiola elegans, Sow. Natica glaucinoides, Sow. In addition to these I have found Cardium Plumsteadiense, Sow. Scalaria. nitens, Sow. Ostrea. But by far the best section, and one showing a considerable length of the basement bed of the London clay, was exhibited on the line of the Great Western Railway at Sonning Hill between Reading and Twyford. The cutting, which is sixty to seventy feet deep and about a mile long, traverses the mottled clays. These are covered in the highest parts of the cutting by three to four feet of brown clay with subordinate and irregular layers of yellow sand, the whole mixed with seams and patches of greensand and with some round flint pebbles. Irregular layers and masses of these materials, cemented by carbonate of lime and full of well-preserved shells, are of common occurrence. (See fig. 12.) A thick bed of ochreous flint gravel caps the section. Bie 2: = ection at Sonning Hill. SBT, Sa eee See IP a. Ochreous flint gravel. a 6, Brown London clay, with septaria. c. Yellow sand, with irregular seams of brown cla and green sand ; a few round flint pebbles, an numerous tabular calcareous concretions. Fossils dispersed throughout, but peculiarly abundant in the calcareous blocks. Thickness varies from 4 to 5 feet. d. Upper part of the sands and mottled clays. Sur- face worn and irregular. =—— = = =— The chalk lies at about 70 to 80 feet below ‘‘c,’’ but is not exposed. * T have found traces of this stratum at several places on the hills both to the N.E. and S8.W. of Theale, but only in small road-side cuttings. f Trans. Geol. Soc. 2nd Ser. vol. v. p. 127. The similarity of the organic re- mains of these beds at Reading, Watford, Hampstead, and some other places, has already been pointed out by Mr. John Morris so far back as January 1837 (Proc. Geol. Soc. vol. ii. p.452). In the determination of the fossils of many of these lists I have to express my obligation to Mr. Morris. ee Se a ae 1850. } PRESTWICH ON THE LOWER TERTIARY STRATA. Organic remains of stratum “cc,” at Sonning Hili. G ; Astarte. Calyptrea trochiformis, Lamk. Cardium Plumsteadiense, Sow. ee Sow. micas: Sbrga: Desh. ovalis, var. ? Sow. Ditrupa plana, Sow. sp: Fusus. Modiola elegans, Sow. depressa, Sow. Nucula. Ostrea puichra, Sow. Panopea intermedia, Sow. Pectunculus brevirostris, Sow. Plumsteadiensis, Sow. Pleurotoma. Rostellaria Sowerbyi, Mant. , nN. Sp. a. Scalaria. Venericardia ? Voluta denudata? Sow. Spatangus. Natica glaucinoides, Sow. Teeth of Lamnze. Hantoniensis, Pzk. The Ditrupa plana, Cardium nu. sp., Cytherea obliqua, Modiolu elegans, Natica glaucinoides, Ostrea pulchra, Pectunculus brevi- rostris, and. the teeth of Lamne, were here particularly abundant. The more hilly character of the country, and the slight dip of the strata, now cause the outcrop of this bed to expand over a wider area, and to take a very irregular line, which can only be followed at intervals. At Holywell near Maidenhead a group of fossils from a bed of this age was described by Mr. Warburton* in 1821. These fossils are now in the museum of the Society, and consist of the following species : Calyptrea trochiformis, Lamk. Natica glaucinoides ?, Sow. Cardium nitens, Sow. Panopeea intermedia, Sow. Plumsteadiense, Sow. Pecten. Cyprina or Cytherea. Pectunculus Plumsteadiensis, Sow. Ditrupa plana, Sow. sp. Pleurotoma. Fusus. Tellina. Modiola elegans, Sow. Teeth of Lamne. In the midst of the chalk district and nearly ten miles to the north of the main body of the tertiaries, I have met with a well-cha- racterized outlier of the basement bed, underlying a capping of London clay, forming the high hill at Lane End four miles west of Wycombe. I found the fossils in blocks of very ferruginous septaria in some small shallow pits on Lane End Common. They were in the state of casts and impressions, and were extremely abundant in some places. They consist of the following species :— Cardium nitens, Sow. , i. Sp. @. Cytherea obliqua, Desh. Calyptrea trochiformis, Zamk. Modiola elegans? Sow. Natica glaucinoides, Sow. Pectunculus Plumsteadiensis, Sow. Teeth of Lamne. Fusus. No good section is exposed. Another small but interesting outlier occurs on the chalk at Tilers’ Hill, one and a half mile east of Chesham. Several brick-pits are worked on the summit of this hill, exhibiting in a series of clear sec- tions the several beds from the chalk to the London clay, which here consists of a brown clay with large septaria. At the base of the London clay is a layer of one to two feet of rounded flint pebbles in sand and clay. To this succeeds a series of sands, with some pebble beds, reposing on the chalk. (The section of this hill will be * Trans. Geol. Soc. 2nd Ser. vol. i. p. 52. 268 PROCEEDINGS OF THE GEOLOGICAL society. ([Jan. 23, given in a future paper.) The organic remains found here during a very short visit were as under :— Cytherea obliqua? Desh. Teeth of Lamne. Natica glaucinoides ? Sow. Returning to the main line of outcrop, we reach, about midway between Maidenhead and Uxbridge, the small village of Hedzerley, immediately to the south-west of which, in a brick-field on the slope of the hill, is a very interesting section first visited by Mr. Morris and myself in 1842, at which time the section was much clearer than I found it last autumn. The abundance and fine state of preserva- tion of the organic remains at this place far surpass anything that we had then, or that I have since, seen in any part of the tertiaries westward of London, excepting perhaps Sonning Hill. The fossils are preserved in large tabular masses of calcareous clayey green sand containing a few rounded flint pebbles, at the base of the London clay, and immediately overlying the mottled clays. (See fig. 13.) Fig. 13.—Section at Hedgerley. aaa a Mixed gravel and clay. == Ob. London clay: 1. brown and bluish clay with septaria ; 2. brownish clay. Fossils scarce in these beds, which attain a thickness of 35 feet at a short distance south- ward. c. Blackish clayey sand and green sand, underlaid by flat tabular masses of green sand with a calcareous cement and full of fossils. The small round flint pebbles not numerous. == = = == === qd. Mottled clays—light greenish grey and red. SSS SE: The chalkis reached at a depth of 45 feet beneath “‘e,”’ 393 Organic remains of stratum “c,” at Hedgerley. Cardium nitens, Sow. Ostrea. —— Plumsteadiense, Sow. Pectunculus Plumsteadiensis, Sow. , i. Sp. & Panopza intermedia, Sow. Cassidaria striata, Sow. Pleurotoma, large smooth sp. Corbula revoluta, Sow. Pyrula tricostata, Desh. Cytherea obliqua, Desh. Rostellaria Sowerbyi, Mant. ovalis, var. ? Sow. -, . Sp. smaller. Ditrupa plana, Sow. sp. Tellina. Fusus, large finely striated sp. Scalaria. , broad smooth sp. Vertebre of fishes. Glycimeris ? Teeth of Lamne. Modiola elegans, Sow. Wood in fragments. Natica glaucinoides, Sow. A boring Mollusk, probably a Lithodo- Hantoniensis, P7k. mus. Nucula. The concretionary calcareous masses have a brown and weathered appearance, and have been here and there bored into by some mollusk. These blocks are literally full of shells, amongst which the Cardium n. sp. a, Cytherea obliqua, Natica glaucinoides, Nucula, Rostellaria Sowerbyi, and the Ditrupa plana, are most abundant. The shells are well-preserved, some with their nacre, but, as at Sunning Hill, their substance is rather soft and friable. ae e/a 1850.] PRESTWICH ON THE LOWER TERTIARY STRATA. 269 Proceeding by Uxbridge to Watford, occasional imperfect indications of this bed are met with. On the Birmingham Railway, at Bushey near Watford, the mottled clays with the basement bed of the Lon- don clay were exposed, in a section which I was too late to see in a good condition. ‘The superposition, however, was sufficiently appa- rent. The following organic remains were found there by the late Dr. James Mitchell :— Cardium nitens, Sow. Cytherea obliqua, Desh. Plumsteadiense, Sow. Nucula. ——., N. Sp. @. Panopea intermedia, Sow. Cytherea ovalis, var.? Sow. Rostellaria Sowerbyi, Mant. Diverging five miles to the south, the chalk comes so near to the surface in the valley at Pmner near Harrow, that it is worked b shafts sunk through the supericumbent tertiaries. The following is a section of one of these shafts. (See fig. 14.) Fig. 14.—Section at Pinner. 6 London clay. 1 abe 1. Large tabular septaria. 2. Sands. 3. 3 Pebble bed. FF —S—SSSSSSSSSSSa_aaa_la__== =S=> \d. Mottled clays (1 and 2) witha few subordi- _—————— 1 nate beds of sands (3). 4. Impure E SSS | green sands with green-coated flints. = SSS __SSSSS= —_SSSL—-_-_==—_=S==—-=S=-_ZaZla=—l=S=== \ ee The works were not in operation at the time I visited this spot, and I was unable to procure any of the fossils said to occur abundantly in the stratum which I have marked “c. 1.” Passing eastward by Shenley Hill, no good section of this bed occurs until we reach a brick-field one mile east-south-east of Hat- field, and immediately adjoming the east side of Lord Salisbury’s park. This pit exposes a complete section from the lower part of 270 PROCEEDINGS OF THE GEOLOGICAL SociETY. (Jan. 23, the London clay to the chalk. It may, with fig. 14, serve to show the general relative position of stratum “e” to the chalk, but ex- hibits neither the thickness nor the variety usual in this lower series. (See fig. 15.) Fig. 15.—Section near Hatfield. E. Ww. . Grayel—roughly-rounded flint, white quartz, and other pebbles, in nearly white sand. . London clay; avery dark grey and brown clay passing down- wards into a yellow sandy clay. . Sandy brown clay, mixed in its lower part with a few round flint pebbles. Organic remains not numerous. (The division between “‘6”’ and “ec”? is not well marked, and should probably be placed lower.) d. 1. A series of thick beds of light yellow and ash-coloured sands, mixed in places with clay. 2. Coarse green sand and clay, full of large, partly rolled, green-coated fiints. f. Chalk. The only fossils I could here determine were an Astarte much re- sembling the species common at Herne Bay, Ostrea, and teeth of Lamne. Fragments and traces of other shells requiring further ex- amination are met with. Thence by Essenden* to Hertford no sec- tions of this bed are exposed. The next one is m a brick-field on George’s Farm, one mile south-east from Hertford on the London road. (See fig. 16.) Fig. 16.—Section near Hertford. ES es Gino a2 siya it-447 a. Brown clay mixed with flint gravel. vo ay London clay; grey and yellow clay passing downwards into dark grey sandy clay. Casts of shells in clay and pieces of soft brown wood not uncommon. The lower part of this probably belongs to Came = = = ¢. Round flint pebbles in brown clay, with a few teeth of SSS SSS SSS SSS Lamne. 4 to 8 inches. = === d. Light greevish sand, with traces of mottled red clay, : passing down into light ash-coloured sand. : > a a! ig ON fik Siw Ace cia feo 22 ou fe The chalk outcrops at a depth of about thirty to forty feet below «“¢2? The organic remains here found in the lower part of “6” and nn “e” are not numerous, and are badly preserved in the form of soft clay casts. Sufficient, however, of them remains to determine with but little doubt the undermentioned species :— * In a well dug here, I am informed that a mass of shells ten feet thick occurred immediately below the London clay, at a depth of 100 feet. 1850.| PRESTWICH ON THE LOWER TERTIARY STRATA. 271 Panopeea intermedia, Sow. Fusus. Pectunculus Plumsteadiensis, Sow. Ostrea. Cardium, n. sp. «? Teeth of Lamne. Astarte ? We now enter upon a tract of country, which is so thickly and uniformly covered by beds of gravel and boulder clay drift, that it is rarely that the smallest section of the tertiary beds is visible. Oc- casionally where the chalk is worked we find a small capping of the sands and mottled clays immediately overlying it ; but taking the line of country by Stanstead, Bishop Stortford, Easton near Dunmow, to Great Yeldham, I have not been able to find a single section of the basement bed of the London clay. Between Yeldham and Sudbury in Suffolk, however, in a brick-field on the brow of the hill near the village of Gestingthorpe, there is a small section in which the basement bed of the London clay may, I think, be identified, although the only fossils 1 could find in it were the teeth of the usual species of Zamna. (See fig. 17.) Fig. 17.—Section at Gestingthorpe*. N. S. SI —————————— 7 Saat Boulder clay drift. SS aa) }, London clay; upper part of brown sandy clay, with the com- mon bluish facets, and containing a few small sandy ochreous | concretions ; passes down into yellowish sand laminated with greyish clay. No organic remains yet found. i] SS eC. Round flint pebbles in sand and clay. Teeth of Lamne com-< SSS mon. No other fossils. d. Bright yellow sands. - The chalk outcrops near the base of the hill at a depth probably not exceeding sixty to eighty feet beneath “c.”’ Continuing over the same irregular hilly district, intersected by narrow and small river- valleys, we pass by Sudbury and Layland to Hadleigh. On a hill one mile K.N.E. of this town, the lower beds of the London clay are worked together with the underlying sands. (See fig. 18.) 18.—Section near Hadleigh. Ay 2/s.7ia. Mixed clay and gravel. 6. London clay; brown clay passing downwards into a dark grey sandy clay, with a few shells and teeth of Lamne. = ¢, Round flint pebbles in sand and clay, with teeth of Lamne. d. Light-coloured sands. SSeS The chalk crops out at a short distance below this pit. * This section, with two near Hadleigh, and three or four near Ipswich, re- quire further examination. VOL. VI.—PART I. x 272 PROCEEDINGS OF THE GEOLOGICAL society. [Jan. 23, The next section is at Whitton Street, two and a half miles north- west of Ipswich. In some fields to the westward of the high road there are two pits, one of which exhibits the following section. (See fig. 19.) Fig. 19.—Section near Ipswich. ———————— =a. Mixed clay and gravel. —————————————— Se, London clay; brown and occasionally light bluish-grey clay, with a few small ferruginous concretions, passing down into SSS slightly micaceous brown clay laminated with ochreous and === yellow sand. No fossils. sand and brown clay. Teeth of Lamne@ not uncommon. No other fossils, ———————————— d. Light ash-coloured sand, with a few small clayey concretions. No fossils, The chalk is not here reached, but it crops out at a short distance lower down the hill, and at a level of not exceeding thirty to forty feet below stratum “‘c.” There are some pits adjoming Ipswich near the Woodbridge road which exhibit sections of the London clay over- lying sands which I believe to belong to the lower Eocene series. I have not examined these pits in detail. Passing on to Woodbridge, we arrive, at a distance of one mile south from this town, and on the banks of the river, at the Kyson brick- field, a spot well known by the circumstance of the teeth of the Monkey having been found there*. The exact position of the bed in which these remains occur has been considered rather problematical, but I have little doubt that it belongs to the basement bed of the London clay+. (See fig. 20.) Fig. 20.—Section at Kysont. 6. London clay. Above this clay, and a little higher on the slope of the hill, the red crag crops out. ce. Round flint pebbles in yellow sand. Teeth of a Lamne common ; those of a species of Monkey rare. This crops “out on the level of the river. d d. Light-coloured sands; depth unknown. Large = —— : Ostr ee said to occur’ in some concretions in the - upper part of this bed. * Owen, Annals Nat. Hist. vol. iv. p. 191. + It has been already assigned by. several geologists to the beds beneath the London clay. x I cannot quite depend upon this section, as I have mislaid my original notes of it. 1850.] PRESTWICH ON THE LOWER TERTIARY STRATA. 273 Organe remains of stratum “c,” at Kyson*. Macacus eoceenus, Owen. Cheiroptera. Didelphys? Colchesteri, Charlesworth. Teeth of Lamne. Hyracotherium cuniculus, Owen. I have found slight traces of fossils in the clay bed ‘‘6,”’ but they were too imperfect for determination. A larger section of the London clay is worked near Melton Street, two miles north-east of Woodbridge. Beyond Woodbridge to the coast the Eocene strata are continuously overlaid by the Crag, and sections of them become still less frequent. On the coast the cliffs at Bawdsley show a section of red crag reposing on the London clay, but these cliffs are not contmued to that point (probably not far northward) where the beds below the London clay would crop out. We have now traced this basement bed of the London clay at in- tervals in a belt wrapping round the tertiary series for the length of 250 miles. In the central portions of the tertiary district, the base of the London clay, although not exposed, is reached in many well-sections. Everywhere the same leading features as we have shown to exist at the outcrop, present themselves at greater depths. The organic remains found in this stratum, unlike those of the London clay, which so generally exhibit internally some form of pyritical or calcareous infiltration giving the fossil a solid form, are usually extremely friable, and have rarely undergone any mineral substitution. The ordinary material of the rock passes into the interior of the shell. The shell itself is almost always preserved, although in a very earthy and friable condition. Still, where care is taken, or when they are imbedded in calcareous masses, they can be obtained in a very perfect state. | Owing to the persistent range of this bed and its distinctive cha- racter, I have, to give it a definite designation for the convenience of reference, termed it “the basement bed of the London clay,” although viewing it always merely as a subordinate member of the London clay. ConcLusION. The preceding descriptions I believe embrace, with two or three exceptions, all the principal sections exhibiting the superposition of the basement bed of the London clay. Although, considering the extent of the line of outcrop, they are not very numerous, the intervals between them are sufficiently short to trace this deposit from place to place with considerable certainty. The details of each may vary * These fossils are as rare as they are curious. They have been found chiefly by the careful and minute search instituted by Mr. Colchester, who, I believe, had the sands and pebbles (‘‘ c’’) frequently sifted and examined on purpose. A like close examination might possibly bring to light similar fossils at other localities, especially at those where the structure so nearly resembles that at Kyson (as in figs. 17, 18, & 19). So scarce are these fossils, that in the short visits I have paid to all these pits (Kyson included), 1 have never found anything but the teeth of the Lamna. xe 274 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 23, in a few points, but they all present a general resemblance. This may not however be considered sufficient for our object—such thin and ordinary beds might be subordinate to some other portion of the Kocene series, and not peculiar to this part of them, and therefore some other proofs of their position may be thought necessary. Tn the first place, all the sections im the tertiary district show, by evidence of the clearest kind, that the London clay forms a nearly homogeneous mass, several hundred feet thick, of tough clay of a predominating brown colour—that throughout its whole body it nowhere presents any subordinate beds of a mineral character essentially different from that of its ordinary argillaceous type—and that its organic remains are very irregularly dispersed, abounding in some parts and being entirely wanting in others. This clay occupies an area which is very well defined. Now wherever, without a single exception that I am aware of, the lower beds of this clay outcrop, there is found underlying them a basement bed of a conglomerate character and with or without organic remains—and these, if present, invariably belong to one and the same group of fossils. Further, if we go more into the chalk district, we shall find that whenever the out- liers of the lower tertiary sands and mottled clays without organic remains, attain a thickness on an average of from 50 to 100 feet, the basement bed of the London clay invariably sets in. Again, this deposit always exhibits a peculiar mineral character, the chief feature of which is the presence of rounded flint pebbles, mixed with yellow, green, or ferruginous sands in variable proportions. Inter- mingled with the conglomerate bed, or in the thin sandy layer above it, are frequently found numerous organic remains belonging to a fauna of about forty species, many of which are persistent throughout the greater part of the range of this stratum. Now although the London clay does not always contain organic remains, nor is the basement bed always fossiliferous, neither is the mineral character of one or the other always exactly alike, nevertheless the concurrent testimony afforded in each case, either by position, or by organic re- mains, or by lithological structure, although the force and value of one or the other class of evidence may vary materially, is I consider, in all the instances I have adduced, sufficiently strong to prove the position assumed. I cannot admit, as has been urged, that the absence of organic remains in the lower beds of the London clay, at New Cross, Upnor, Gestingthorpe, Kyson, and elsewhere (see Sections 8, 10, 17, 20), is an argument against such beds forming part of the London clay. It is not possible to take up a position upon a mere negative fact—to use as substantive evidence that which of itself is but a difficulty arising from variable, and not from conflicting, conditions. If the “massif”? of the adjoming district consists of London clay, and the dip and position of the strata, as well as their mi- neral characters, lead us to suppose that these beds crop out im the position which should be occupied by the lower beds of the London clay, then I hold that as such they must be considered, unless they can be proved to be something else. Otherwise, in trymg to avoid one difficulty a more formidable one will be raised, in having 1850.] PRESTWICH ON THE LOWER TERTIARY STRATA. 275 to reduce into harmony with the phenomena of the surrounding district that, which in this case would become an exceptional phe- nomenon. We should rather seek, by an inquiry into the conditions regulating the distribution of organic remains in the London clay, whether a sufficient reason can be assigned for the absence of organic remains in these portions of the London clay, and to discover how far the phenomenon is a local or a general one. In Hampshire and the western part of the London tertiary district, the organic remains of the London clay are dispersed with tolerable regularity throughout the whole of its mass, whereas eastward of London the lower beds of the London clay contain, as a general rule, few or no fossils. The fact therefore of the scarcity of organic remains in the lowest clay beds of the London clay ina large portion of its range is a prevailing and not an exceptional feature. It is not alone apparent in those sections where we find only a small extent of the London clay exposed, and on which consequently doubts have been thrown, but also in those sections where we have the successive beds of the London clay exposed from its base up to its well-characterized central beds. Thus im the extensive section in the cliffs adjoining Herne Bay, the base of the London clay is almost, or entirely destitute of fossils, whereas as we reach the beds higher in the series, which are seen gradually setting in, the well-known fossils of this formation become far from scarce. So also at Guildford the lower beds are unfossiliferous, but in proceeding along the dip of the beds towards Woking, organic remains become tolerably abundant. I have in a previous paper* argued the probability of the London clay of Hampshire having been deposited during a period of a nearly constant, regular, and tranquil subsidence of the bed of the sea, whereby a nearly uniform condition of the sea-bottom, favourable to the pro- longed existence of the same group of testacea, was maintained. I also concluded that the subsidence had been greater to the north-east than to the south-west of the Tertiary district, and it therefore follows that it must have been more rapid in the former direction either throughout the whole, or else during particular intervals, of the London clay period ; and consequently if the rate of that subsidence was at any time more rapid than the silting up of the sea-bottom, it would result that at such times the sea would become deeper in the north-east than the south-west. Under these conditions we might expect a distribution of the fauna in the north-east of the tertiary district different to that prevailing in the south-west. Now, if the accumulation of the lower part of the great mass of clay forming the London clay commenced during a sudden or even a tolerably rapid subsidence of the sea-bottom i the north-eastern portions of the tertiary area, then the shallow sea fauna of the basement bed could not under these altered conditions of increased depth have been tran- quilly transmitted upwards as in the Hampshire area, but must for a time have ceased to live in districts so affected, and, before a deeper sea fauna were introduced, strata might have been deposited with few or no organic remains. * Quart. Journ. Geol. Soc. vol. iii. p. 354. 276 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. {[Jan. 23, After a time, however, the inhabitants of deeper waters would gradually immigrate ito these parts of greater depths, and there remain, until from some cause the sea became again sufficiently shallow to allow of the incoming of shallow sea testacea, and then that original fauna, which in the interval had been preserved in the same sea, in the distant Hampshire tertiary area, might have extended itself and reappeared in that part of it spreading over the more central and easterly parts of the London tertiary district. This I consider to have been the succession of events at this period of the tertiary epoch. On this supposition I account for the absence or extreme scarcity of organic remains in the lower part of the London clay in the central and eastern divisions of the district, and for their abundance in the western divisions. In the neighbourhood of London, as we ascend in this formation, we meet with remains of Cephalo- podous testacea in strata succeeding the lower unfossiliferous beds, and we find them further eastward with the remains of Cephalopoda, of Echinodermata, and of other denizens of deeper seas, in some abundance. The lower beds of the London clay overlying its basement bed, may therefore from this cause without difficulty be conceived to present, although synchronous, considerable modifications in their organic remains, whose presence or absence taken separately does not consequently afford a test in this case to the determination of the geological horizon. We now have to consider the physical changes indicated by the structure of the basement bed itself, marking as it does the passage from the arenaceous beds below to the argillaceous ones above it. Of the conditions of the sea preceding this period we shall treat on a future occasion. Indiscriminately over all the variable ‘‘ Lower Eocene” deposits spreads the basement bed of the London clay. It is the first brush of uniformity, where previously all had been different. Extending from the Isle of Wight to Woodbridge in Suffolk, this bed presents some general characters of remarkable persistence. In the first place it is evident that it does not form a sequence in structure conformable to the beds which it immediately overlies. Yet no fresh element is introduced at first into its composition. Although the materials composing this bed are not in many cases found in any of the beds immediately below, yet they all exist in the underlying series in some part of their range, and are, I believe, derived from that source. The great depositary of the rounded flint pebbles in the under- lying beds, are the estuary and fluviatile strata of Woolwich and Bromley, where they occur in remarkable abundance. Associated with these pebble beds are thick beds of yellow sand and also several subordinate beds of a strong coarse green sand (which become, how- ever, much more important in East Kent), some beds of a deep ferruginous character, and a few clay beds—the mottled clays of the western districts also are interstratified with beds of yellow sands, but without pebbles. Now the pebbles of the basement bed of the Lon- don clay have been probably derived from those previously accumu- lated locally in these underlying beds, and, if the pebbles, then also 1850.| PRESTWICH ON THE LOWER TERTIARY STRATA. 277 the various sorts of sand associated with those beds, were also likely to have been thus derived. I hold this opinion because this base- ment bed does not present these different substances in separate and sedimentary order—the bed is composite, and its materials derived, not by a river action bringing down sediment into the sea, but, if I may so term it, by apparently a scouring and general sea action on the pre-existing and underlying beds. That the pebbles in this bed are not in the position in which they received their present form, is, I think, evident from the excessive and lengthened attrition which the flints must have undergone to have formed pebbles of such uniform roundness and finish—a state of things incompatible with the co- existence and preservation of the remains of a delicate and abundant fauna in the same stratum. But we have other and independent proofs of this bed having originated in the destruction of part of the underlying beds. Thus in Section, fig. 1, at White Cliff Bay, it has been shown that rough pebbles of red clay, derived from the harder parts of the underlying mottled clays, occur in this bed ; and in Sec- tion, fig. 11, at Herne Bay cliff, I have found in this bed specimens of the peculiar uncouth green-coated flints, which form the charac- teristic bed, reposing almost everywhere in this country and in the North of France immediately on the chalk. These half-rolled green- coated flints have an appearance so perfectly distinct and constant, that their origin cannot for a moment be doubted. Therefore it is probable that the denuding action acted not only on the mottled clays and the pebble beds forming the upper part of the underlying series, but that it in places extended to the chalk itself. It is doubt- ful however whether the latter suffered much denudation at this time. There are but few traces of its direct debris in this bed. The pebbles of flint I suppose to have been derived from a long-continued wear- ing away of the chalk at a previous period. The disturbance at the period of the basement bed of the London clay does not appear to have acted with sufficient power on the chalk, nor during sufficient time on the flints, to have produced a large destruction of the former, or to have reduced the latter to the state of such well-rounded flint pebbles. The irregular and worn upper surface of the lower beds of sands and mottled clays, upon which the basement bed of the London clay reposes, is a corroborative proof of their partial denudation prior to the deposition of the latter. The erosion is certainly not very great, yet it forms an extremely well-marked phenomenon, as at Sonning Hill and Guildford (see Sections 6 and 12), at which latter place it has removed all but a few patches of the Woolwich beds. In the western parts of the London tertiary district it has worn to some extent into the mottled clays. That the setting-in of this denuding action was sudden, is evident from the abruptness of the change; of its force, the size of the transported pebbles, and the amount of erosion, lead us to judge that it was moderate; and that it was not of long duration is evi- denced by the thinness of the deposit. The erosion is more apparent, and the exhibition of transporting force greater, on the southern flank of the tertiary beds than on the 278 PROCEEDINGS OF THE GEOLOGICAL society. [Jan. 23, northern. It was at this period that the great break appears to have taken place between the English and French tertiaries ; for up to this point, the sands, mottled clays, and fluviatile beds are common to both countries, and present much similarity of structure. But at this level the resemblance ceases; the London clay sets in with its great argillaceous character, whilst in France this period is succeeded by a series of light-coloured, calcareous, and generally very fossili- ferous sands and earthy limestones. I do not think this separation of the two districts to have been caused by the elevation of the Wealden: in the first place, because the London clay is found in nearly equal force on both sides of the Wealden elevation; and in the second place, because there is evidence (see Sections 4, 5, and 6) that that elevation affected these Eocene strata equally with the secondary ones. It would appear therefore, on physical grounds, that the denudation acted from the southward, while it has been be- fore shown, on palzeontological evidence, that in this same direction there was probably a considerable rise of the sea-bottom, accompanied by a slight subsidence to the northward. To the disturbing action of the waters flowing off from the sea-bottom thus raised to the southward, I attribute the first spread of the basement bed of the London clay and the partial denudation of the underlying strata. The elevation of the bed of the sea was not sufficient to convert it into dry land, nor was the change of that violence to destroy, over the whole area acted upon, the animal life of the period. In distant or in more sheltered parts of the sea, as before mentioned, some of the testacea which inhabited it were preserved and transmitted into the deposits formed subsequently to these changes. The basement bed of the London clay contains altogether thirty- one known species of testacea, and apparently eight to ten undescribed species. In Hampshire and in the western division of the London district there are in the underlying strata no remaining traces of any older stock whence this new fauna could have been derived. From London, however, through Woolwich to Upnor, this bed reposes upon fossiliferous fluviatile beds, and here apparently there seems te be a transmission upwards, from one period to another, of some of the species, as the Cyrena obovata, C. cuneiformis, C. tellinella, Ceri- thium variabile, Melania inquinata, and Pectunculus Plumsteadi- ensis, which abound in the estuary and fluviatile beds of Woolwich*. Some of the species also from the lower marine deposits of Herne Bay and Sandwich range upwards into the ‘‘ basement bed,” as the Corbula revoluta, C. longirostris, Natica glaucinoides, and Pectun- eulus Plumsteadiensis, and probably the Cyprina Morrisu. There is this difference, however, between the species introduced from the underlying beds, and those which constitute the typical and universal group which will shortly be alluded to, viz. that the former are, with the exception possibly of the Cyprina Morrisiz, confined in their range to a limited region, surmounting or not extending much be- yond (2. e. at this period) that previously occupied by them, whilst the latter have a general and unlimited range. * Out of these six species four even liyed on to the period of the freshwater series of the Isle of Wight. Ris : Be ‘\~ ye ehh a ea i te mieanb whee pape aA Wit Les Faia were “a ci 8 i para adgreneey ote amine uk hon TS rs ie bE RY vt we tT Pi Le ad (artie gob FOL MeL t% hic ee oy bal mt Ce me a sige Aa! Prade MOAS OARS ll vphath ions tibrah ny Ange? ey ole ewe aprtlbt oem’! 7 ee hoo eo * P i i , 4 a ere se Hi Finite wed eg = ee ; ' het { x a | Bines. ne a oe ie FT alee cl chicane Auda hae te PRC Wot DRA Bh bide ig eaR > ERR) Grow: are yr, ye be . i VL CR Fe RE RE TEES oH Derr epoty TR) eth Shey: halo Ce tnals, Ripa ES SC + uy See Taare aed betLiahl capt A ei led 3 we Semi inp ycanaacioieel stoahaakaety Hehe dade aah helps ‘ hed hid he AZT. Longdeaitas ieee : ashes by + TaBLe A.—Showing the general range and distri Note.—The line of range is taken from the Isle of Wight north tdive Conchifera. Mollusca. geographical distances. Where there are breaks in the ks at any given place. The last two columns show the furthe (.Ditrupasplanay Sows sps .c2-2dstsc00-h02- Panopza intermedia, Sow...............- Corbula revoltta, Sow. 2...0000..0.00222 — obovata, Sow Nucula margaritac Modiola depressa, elegans, Sow. lONPITOStTISS Desi 5-5 <2 So S Sa 2 . nt 2 “4 Ze A saaaNG * CSE Sy” Pr NS ; 2) Ase ose] SSS *OAODSO | ("43 OOTE ’ : yp Ted oJUOTT aN : Cild ‘ a aqU0 IAT oVUOTAL edeg ip 800071 ‘dureg §,yeqruue xy SET wnIgwT ayy fo uopoag—'p “SU ‘jueur ouruuedeqng '7 ‘ong ‘ouvjonzznd ‘ourseded “yn, *p ‘qyeseg °2 ‘soyqqod pur purs ouruuedeqng 7 “9 vee oped “76 xs A5°9, if *BUdSTOR ER SO, OW oF qa Leah 2; @ S z jo ox[B'T Qe Gig Gay Pp 3 ory “4Teseq JO sluqod ‘OZUALOTT "3S ‘oyuopuodenboy ry ‘a's 5 8 “tuvjooIpery ‘AN ‘aquapuadonbop 70 W01ZI0g—" | “oly JCANIC ROCKS OF ITALY. 285 MU RCHISON—EARLIER VOLC 1850.1 OZ Ssss \ nn | i} | l oo ~ Ss = Cy | Se i ) | | -ouezuey *f | 5 - 0 ® o oO eo a ee) > 8 SaGseSSeess a a4 | | | I h Wa | mh / "I}OTIPA “7 erootloye A *a 286 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb, 6, is built*. The still higher plateau, south of the town, is occupied by great thicknesses of the well-known yellowish tufa of the Campagna, fig. 1 d, in the puzzuolana o# sandy beds of which many caverns have been excavated. Now, if the “ tephrine lava”’ had happened to con- tain zeolite instead of leucite, any British geologist might call it a trappean greenstone ; and, as it is, there can be no sort of doubt that these Italian earlier volcanic products are as much of subaqueous origin as the blue shelly marme marl and sands which they have traversed, and which they immediately overlie. In descending from St. Lorenzo to the Lake of Bolsena, the hard leucite rock is seen to contain crystals of pyroxene, hornblende, felspar, and mica. Occasional fragments of secondary Apennine limestone also occur in this rock, but leucite is the dominant mineral. This leucitic rock is encased in a vast thickness of tufaceous, sandy or marly tufa, im parts a peperino, in parts scoriaceous. It is in this feature of being more scoriaceous, and in here and there having a rough or trachytic aspect, that these eruptive rocks, whether ba- saltic and compact or loose and scoriaceous, more resemble modern lavas and their accompaniments than our British traps. But I ob- served nothing like a regular qua-qua-versal or outward dip from the Lake of Bolsena. The Marquis Pareto, however, who examined the whole circumference, speaks of a slight outward inclination ; but even if it be so, on those sides of the lake which I did not examine, there is little or no analogy between such an arrangement and the highly inclined dejections of a subaérial voleano. Pareto’s words are only to this effect : “‘ Questi banchi inchmano generalmente pit al di fuori, che verso il centro della cavita medesima.” The hard, compact leucitic rock, which occurs near the summit of the escarp- ment at the north end of the lake, is again found very little above its level to the south side of the town of Bolsena, where it ranges in devious columnar masses, not unlike many of our prismatic basalts, and is composed of numerous pentagonal and hexagonal columns, the ends of which vary to different angles with the hori- zon, depending probably upon the outline of the cooling surfaces of the pre-existing materials with which the eruptive lava came in contact. Further southward, z. e. on the east bank of the lake, whitish claystones, in parts having a semi-pumiceous or trass-like aspect, alternate with courses of grey-coloured scoriaceous lava. Few persons, who have examined this country, will, I apprehend, be dis- posed to doubt, that the trachytes of Tuscany and the Papal States are among the oldest of these earlier volcanic rocks. Of this, in- * In Brongniart’s classification of rocks, the basalt of Radicofani is called ‘‘ Té- phrine pavimenteuse,”’ and is associated both with the lava of Volvic, in Auvergne, and with a production of Monte Nuovo in modern times. And yet nothing can be geologically more distinct than the periods of eruption of these three rocks. Again, the basalt under Acquapendente, which geologically, in my opinion, is simply a varied mineral prolongation of a band issuing from the same centre as that of Ra- dicofani, is distinguished as ‘‘ Téphrine amphigénique,” merely because it happens to contain imbedded crystals of amphigéne or leucite.— Classification des Roches, pp. 118-119. 1850.] MURCHISON—EARLIER VOLCANIC ROCKS OF ITALY. 287 deed, the Marquis Pareto has afforded undoubted proof by his descrip- tion and sections explanatory of the structure of the tract south of Viterbo*. Monte Soriano, for example, which the traveller to Rome from Viterbo leaves upon his left hand, and which rises to about 3300 feet above the sea, is essentially a mass of trachyte, overlapped by these tuffs and scoriaceous accumulations, which encumber the sides of the road at L’ Imposta between Viterbo and Renciglione. These latter deposits only, according to Pareto, could have had an uninter- rupted communication with the atmosphere. The priority of the trachyte, or its formation under different conditions, is, as I shall here- after show, a pomt of considerable importance in its bearing on the question of the origin of Recca Monfina in the Neapolitan States. * For a more special description of the western part of the volcanic region of the Papal States than is offered in my sketch, I refer the reader to a memoir of the Marchese L. Pareto, entitled ‘‘Osservazioni Geologiche dal Monte Amiata a Roma.” (Extract from the Giornale Arcadico, Roma, 1844.) This author, by an appeal to natural sections, proves that of the volcanic rocks, as distinguished from plutonic, trachyte is the most ancient, and that at points east and south-east of Viterbo, that rock, resting at once on tertiary marine strata, is covered by pumiceous aggiomerate and volcanic tuff. All the trachytic masses which I have seen in Italy, conveyed to me the idea that they had issued in a pasty state, so as to form domes and flattened cones, which, traversing the pre-existing strata of subaqueous origin, were the precursors of all the other volcanic productions of the peninsula. ‘The numerous varieties of trachyte, its crystals of riaccolite, its lithological divisions into fire-stones, paving-stones, &c., and its metamorphic influence on the con- tiguous deposits, do not come within my present object. (See the works of P. Savi, Pareto, Pilla, &c.) All the subsequent volcanic products of the Papal States are grouped together by Pareto under the heads of tuff with peperino, and lava with lapilli. He believes that all the tuff with peperino and solid ag- glomerates were formed and arranged under water, whilst the eruption and fall of the lapilli may have occurred at points in connexion with the atmosphere. He gives a full account of the form and structure of the dejections all around the great cavity of the Lake of Bolsena, and is disposed to think, that its parasitic and crateriform depressicns, occupied by smaller lakes, may be craters of elevation. Although no one of these cavities—not even the Lago de Vico—seemed 1o me to fall into the same category as the extinct true volcanos of Auvergne, still I agree with Pareto, that some of the scoriaceous and pumiceous materials, particularly on the plateau south of Viterbo, were probably ejected into the atmosphere. These have, I admit, so subaérial an aspect, that they may well represent the last operation in a series of volcanic eruptions, which terminated as the grounds rose, by throw- ing up much matter into the atmosphere. Whilst Pareto believes that the depres- sions near L’ Imposta and the Lake of Vico may have been craters whence the leucitic and hornblendic ‘‘tephrine”’ basalts or lavas flowed, he thinks, as I do, that by far the greater portion of every volcanic eruption, even ir these Colles Ciminil, was Subaqueous. In my opinion, such outbursts as that of Graham’s Island would explain all, even the most recent, of the volcanic phenomena in the northern Campagna and the region around Viterbo. The post-pliocene shelly formations on the coast of Civita Vecchia, which are loaded with numerous fragments of the earlier volcanic rocks of which we are treating, show that these last mentioned were consolidated anterior to the accu- mulations of that ante-historic sea, This evidence tends also to prove, that although, even at that time, so remote in respect to our day, the mollusca living in the sea were the same as those which now inhabit the Mediterranean, the physical geography of the coast of Italy must have been widely different from its present outline ; and that as hills, that are now 300 feet above the sea, were then beneath it, so all the lower countries of the Campagna must have been then under water, whether salt, brackish, or fresh. This point will be again adverted to in treating of the Latian volcanos. VOL. VI.—PART I. Y 288 ~ PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 6, But, if for a moment we were inclined to suppose that such rocks as the tuffs of the Campagna might have been formed under the atmo- sphere, all doubt would be dispelled by finding them associated with, and covered by great thicknesses of water-worn, pebbly detritus. In short, when we follow these dejections from Monte Fiascone to Viterbo and the lakes of Vico, Baccano, and Bracciano, up to Monte Mario and the gates of Rome, we see that their very upper- most dejections are so intimately associated with the upper sub- apennine strata charged with marine shells and water-worn rounded. pebbles of apennine limestone, that all doubt is dispelled, and we are compelled to conclude that all, or nearly all, such earlier volcanic rocks as I have hitherto alluded to, and which occupy the Campagna, were formed either entirely under the sea, or m that condition of things when the former bottoms of seas were emerging and were covered with brackish or impure lacustrine waters. Many of these rocks may be included in the peperino of Brongniart ; and although Brocchi attempted to divide them into stony, as distinguished from granular tuffs, and a third variety that may be called earthy tuff, I quite agree with Pareto, that all such divisions depend on mere local accidents and have no sort of geological bearmmg. All these rocks, however varied, constitute in fact but one formation, from the fari- naceous tuff of Monte Verde, near Rome, to the more solid tuffs and leucite lavas of the Ciminian Hills. I have thus dwelt on the true nature of these rocks, in order to attach what I consider to be the right meaning to the words ‘“‘craters’’ and ‘ voleanos,”’ which have found their way mto the descriptive hand-books of Italy, and which may lead tourists to fancy that there were formerly many volcanos like Vesuvius and Etna in this region of the Papal States. Of the older class of volcanic rocks I will now cite a few other ex- amples. The deep ravine near Monte Fiascone exposes on its sides fine sections of rocks, the high antiquity of which in relation to the present condition of things is further mdicated by their having afforded the materials for those huge rounded blocks of peperino, &c. which are strewed over the slope extending from Monte Fiascone into the sterile valley north of Viterbo, in which the well-known Bulicami, or hot springs, have their issue. All these blocks were manifestly trans- ported by great aqueous currents*. It is in the sandy varieties of this group of rocks called panchina, puzzuolano, &c., that far the greater number of the Necropolises of the Ktruscans were excavated, as well as the crypts and subterranean sanctuaries of the earlier Christian martyrs and refugees in the en- virons of Rome. He who visits the site of the ancient Etruscan city of Veii may at once verify this observation ; for whilst the fortress stood on the harder rocks (leucite lava, &c.), the tombs of the Necro- polis were burrowed out of the softer sandy tuff to the north of the city, which is manifestly a finely laminated subaqueous deposit. In the same way at Volterra, where the rocks are not of igneous origin, * The formation of the great globular concretions of peculiar travertine by these * bulicami” of Viterbo are described in Lyell’s ‘Principles of Geology,’ 7th edit., p. 243. 1850.] MURCHISON—EARLIER VOLCANIC ROCKS OF ITALY. 289 but are simply the subapennine clays with yellow sands and sand- stone, we see how the Etruscans, building their city on the former, constructed their tombs in the dry and easily worked strata of the latter, the “panchina”’ of the Italians. Tufaceous dejections and erupted rocks containing leucite similar to those already described, occupy large portions of the Papal Maremma. They are also parti- cularly well developed in that undulating low country which con- stitutes the north-western part of the Campagna and extends from Monterosi by Nepi to Civita Castellana. The cliffs and deep denu- dations of the last-mentioned place are very striking, and the right bank of the Tiber near Borghetto is instructive in exhibiting the pebble beds of the upper subapennine period surmounted by leucitic lava, thus unquestionably proving, that this igneous rock was poured out under the waters, whilst still lower down in the valley there are re- aggregated heaps of a later aqueous drift, in which leucitic rocks and the debris of pre-existing pebble beds are all mixed up together; a condition of things in all respects analogous to that which I have described as occurring at Ponte Molle near Rome*. Again, in passing by Eropete and Castelluccio to Otricoli, pebble beds composed of Apennine limestone are seen distinctly to alternate with volcanic tuff. Associated with these subaqueous volcanic de- jections of the Papal States, are travertines which have evidently been formed at different periods. Thus, near Siena, the accompaniments of the voleanic phenomenon are almost confined to a copious evolution of travertine, loaded with coarse angular blocks of younger secondary limestone, occasionally two and three feet in diameter, which are honey- combed throughout and associated with tuff, marl, &e. These masses immediately overlie the subapennine marls and sand, and are covered by lacustrine limestone with Lymnee and Planorbes ; and this again by sandy loam with land remains and coarse alluvia. Travertine past and present.—The sequence of strata in the southern parts of Tuscany just mentioned, shows very clearly, that the purely marme condition of the strata under which the sub- apennine sea-shells were accumulated, gave place gradually to other subaqueous conditions, in which, after many “ quasi”’ volcanic erup- tions, accompanied or followed by the formation of much traver- tine, those conditions were at length termimated by a more purely terrestrial state. Evidences in the Campagna di Roma still more completely sustam this view. Spada and Ponzi have, it is true, found fragments of an older travertine in the tuff of this region}, but they admit, that the chief masses of travertine (principally formed under water) are of a date posterior to the earlier volcanic rocks I have been describing. In my former communication} I exhibited a dia- gram showing how the lacustrine travertine of Ponte Molle belongs * See Quart. Journ. Geol. Soc. vol. v. p. 296. t Savi describes a travertine in the Pitigliana in Tuscany, which is covered by volcanic tuff and peperino. Such cases are, however, exceptional, and Pilla admits that the great masses of ancient travertine are of the younger pliocene age.—Saggio Comparativo dei terreni, &c. p. 25. ~ See Quart. Journ. Geol. Soc. vol. v. p. 296, fig. 40. y 2 290 PROCEEDINGS OF THE GEOLOGICAL society. [Feb. 6, to that posterior date, and there can be no doubt, that from the pe- riod when the lower grounds were still much under brackish or fresh water, and when travertine was formed in broad ancient depressions then occupied by waters which are now reduced to the rivers Tiber and Anio, there has been a more or less continuous formation of tra- vertine. In order, however, to draw a clear distinction between the former energy of nature in producing travertine under conditions different from those which now prevail, let us appeal to Tivoli and its environs. There we have fortunately exact chronometers. There we can compare the enormous ranges of this calcareous deposit which were elaborated long before man could have trodden the soil, with those small additions which have been made by the river Anio since the foundations of the Etruscan and Roman buildings. Fig. 2.—Section at Tivoli. -—i FO 40) oa 1850.] MANTELL ON THE GEOLOGY OF NEW ZEALAND. 319 Cucullea inflata, Romer, but the umbones are not so prominent, and the posterior angle is more acute. Locality. Kelloway rock, near Trowbridge. EXPLANATION OF PLATE XXX. Fig. 1. Nucula Phillipsii. Fig. 4. Corbula Macneillii. Fig. 2. Astarte carinata. Fig. 5. Arca subtetragona. Fig. 3. Astarte? Fig. 6. Ammonites Reginaldi. 2. Notice of the Remains of the Dinornis and other Birds, and of Fossits AND Rock-spEecimENs, recently collected by Mr. Waiter Manrewt in the Mtppie Istanp of New Zea- LAND; with Additional Notes on the NortTHEerRN ISLAND. By Gipron AtgEerRNon Mante tt, Esq., LL.D., F.R.S., G.S. &e. With Note on Fosstutrerous Deposits in the M1ipDLE Istanp of New Zeauanp. By Prof. E. Forsss, F.R.S. &c. THE remoteness of New Zealand, and the long period required for the transmission of specimens to England, together with the very limited information we at present possess of the geology and paleeon- tology of that interesting antipodean colony, impart a certain degree of importance to any accession of knowledge, however slight, relating to the physical structure, and the ancient fauna and flora of those distant islands. These considerations induce me to submit to the Society the fol- lowing remarks on a large collection of the bones of several species of Dinornis and other birds, of rock-specimens, and of fossil shells, co- rals, and infusoria, received a short time since from my eldest son, Mr. Walter Mantell, of Wellington; and although the information afforded by this collection respecting the geological structure of the country is but scanty, I would fain hope that this brief communica- tion will not be deemed an uninteresting supplement to the memoir on the Fossil Birds of New Zealand, which I had the honour to lay before the Geological Society in 1848. The specimens were accompanied by numerous sketches of the country, and a copy of the official report on the colonial capabilities of the eastern coast of the Middle Island, from Kaiapoi to Akaroa in Banks’ Peninsula, and thence to the Scotch settlement at Otago, a distance of about 260 miles, made during my son’s exploration of that tract in 1848, as Government Commissioner for the final settlement of native claims. Such parts of this report as throw light on the geology of the Middle Island of New Zealand, together with remarks on any parti- cular locality, are embodied in the following extracts. As an apology for the brevity of his notes, my son dwells on the arduous character of a pedestrian journey through a country but very thinly inhabited ; the engrossing nature of his official duties, and the limited time VOL. VI.—PART I. 2A 320 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 27, allowed him, in the most unfavourable season of the year, for the accomplishment of the object of his mission. Premising, therefore, that the route was restricted to the sea-coast, diverging inland only when the depth and force of the streams that empty themselves into the sea rendered their passage dangerous, and compelled a detour to a more narrow or shallow part of the river-channels, and that no leisure was permitted for the accurate investigation of geological phenomena, I proceed without farther comment to the extracts from my son’s note-book : I will afterwards briefly describe the specimens of rocks and organic remains, and conclude with a few general ob- servations on the facts submitted to the consideration of the Society. Fig. 1.—Sketch of the Geology of part of the Eastern Coast of the Middle Island of New Zealand. By WALTER MANTELL, Esq. CANTERBURY PLAINS. oe e on S on a Arowenua Bush. = eS ————— 5 oe E. Bin Fes - SS Watkour ul o* iil i <. % = NS a é SS = a ae Zn8 ‘ \= ar ab If S, aS # ee % ‘ x uae PSS = Bt ry = me we N <2 f9:.. Ototara.\ = ey i Anaamatara. “!AS<¢ ale SY The Bluff. oe Se Onekakara. zs » = Moeraki. : SHITE be <= Katiki Bay. hela? - RS Matakaea. OCEAN. o« + Waikouaiti and Island Point. *S22= Brinn’s Point. »*2== Blueskin Bay. Purakaunui Bay. Otago Bay. : Gaz] Primary and volcanic: —<—<$— ’ az Slate, and quartz conglomerate. > rere Ototara limestone. > Tertiary blue clay. wos Green gritty marl. =—— fim): Diluvial. Molyneux River and Bay. {uuu Boundaries of the block. rape 1850.| MANTELL ON THE GEOLOGY OF NEW ZEALAND. 321 Extracts from Mr. Walter Mantel’ s Notes.—“ Banks’ Peninsula, in the centre of the east coast of the Middle Island of New Zealand, is chiefly composed of a group of mountains of igneous origin, appa- rently the result of submarine eruptions. The two principal har- bours, namely Port Cooper (now called Port Victoria), and Port Levi (now Port Albert), are separated by a lofty range almost desti- tute of wood ; along the crest of this range metamorphic rocks crop out, dipping eastward, whilst on the opposite side of Port Cooper they incline at a considerable angle to the west. “From the summit of a hill at the south-west angle of this Penin- sula, a magnificent view is commanded of those extensive plains which stretch from the Double Corner, a headland north of Port Cooper, to Te Timaru, a distance of 130 miles. Below is seen the dreary ‘Ninety-mile Beach,’ which is a continuous line of shingle without bay or headland. Within the northern part of this shingle-bank is the lake Waihora, which is eighteen miles in length. In the middle distance, plains of vast extent stretch out, and are bounded by that part of the snowy mountains, now called the Wakefield range. The level country consists of a substratum of slightly coherent gravel, principally composed of pebbles of schist, jasper, and white, yellow, pink, and green quartz, covered by a layer of rich loam, which varies in thickness from a few inches to ten feet. ‘These magnificent plains extend uninterruptedly from thirty miles north of Port Cooper to 100 miles south of it, having an average breadth of thirty-five miles. From the sea-shore to the ridge of high mountains covered with perpetual snow, a gentle rise only is perceptible ; but it is probable that near the foot of the mountains the elevation of the plain above the level is not less than from 350 to 400 feet: there is likewise a slight rise to the south, for at Te Taumutu the land is but eight or ten feet above the sea-level, while at Hakatere it is at least from thirty to forty feet. “* Along the junction of the plain with the Peninsula there are many isolated sand-hills ; and farther north, the river Waimakariri near its mouth cuts through a bed of finely laminated sand, under which, at a depth of about ten feet, there is a deposit of various kinds of wood, that appears to have been drifted down when the mouth of the stream was some miles inland of its present position, and the Peninsula an island, and the plain covered by forests, of which a few vestiges only remain. A similar deposit of wood is said to exist near where the Wai- kirikiri discharges itself into the Waihora. Should future examination prove that these vegetable accumulations have been drifted to their present sites, and not have resulted from forests that grew on the spot, it may be inferred that Banks’ Peninsula has but recently been united to the main land, and that the western shore of the lake Wai- hora formed, at no very distant period, part of a bay of the sea. ‘The wood from the above localities is so little changed, as to serve for fuel to the natives of the neighbouring district. It has the usual appearance of the drifted trunks and branches that are stranded on the beach, and burns in the same mouldering manner*. * “ The natives informed me, that at a day and a half’s journey aes of Tau- A 322 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 27, “The rivers that intersect the plain are generally rushing torrents, which have excavated deep channels; they mostly terminate in a lagoon, separated from the sea by beach: through this barrier of shingle some of the streams periodically burst, but others always discharge themselves by filtermg through the bar. The water of a river on whose bank we were encamped, and which was completely blocked up by a dam of beach twenty feet high, fell two feet durmg the night. “The Waihora and some others of the lagoons are opened peri- odically by the natives, for the purpose of capturing the fish with which these waters abound. Numerous narrow trenches are cut, and as the water gushes out, nets are spread, and eels, &c. caught as they are carried down by the stream. A trench about two feet wide will yield some hundreds of eels, three or four feet long, in a single day. In a short time the rushing waters wear away the intervals, unite the trenches, and scour away the entire barrier; the lake ra- pidly sinks to the sea-level, and leaves dry a tract from a quarter to half a mile in breadth; the tide then ebbs and flows into the bay, till a southerly gale drifts in the sand and shingle, and the bay is again converted into a lagoon. Each of the largest rivers has an extensive denuded tract at its mouth, commencing a mile or two in- land, and gradually widening towards the sea; and this is intersected by flood-channels. These triangular delta-like areas are bounded by cliffs, and have evidently been produced by the wearing down of the table-land nearly to the sea-level. “From Rakaia to Wakanui the water from the interior finds its way through the gravel bed, and by undermining it, has formed along the sea-board innumerable chasms and gullies, which are yearly creasing in depth and length: the country here has no other drainage. Some of these gullies or subterranean courses are from one to two miles long; and it seems probable that many of the now open river-chan- nels of the plain have originated in this manner. ‘* Scattered here and there in the immediate subsoil of these ex- tensive plains, bones of the larger species of Moa have occasionally been found: I could not ascertain that any had been observed in the more ancient diluvial deposits ; but I believe that, sooner or later, the swamps and. river-beds will yield a rich harvest of these interesting remains. «* At about ten miles south of the Waiteruaiti the plain ends in the undulating country of Timaru*. ‘“‘The superficial deposits of Timaru are of the same nature as those of the plains, and are superposed on a vesicular volcanic rock, which mutu there is coal in constant ignition, and that they are in the habit of procuring fire from it when they travel that way. In the Chatham Islands a bed of burning peat or lignite is also said to occur; a native of Taumutu, who had seen it, said the substance burning on the plain was very different.” * “ About ten miles inland of 4rowenua, the Kauréke—the only native quadru- ped besides the field-rat in which we have any reasonable grounds for believing— is said still to exist.” My son gives a long account of the appearance and habits of this unknown quadruped, derived from the most intelligent natives, but which would be foreign to the present notice.—G. A. M. 1850.| MANTELL ON THE GEOLOGY OF NEW ZEALAND. 323 reaches a height of fifteen feet, and, gradually dipping to the south, disappears in the course of a few miles. The country then resumes its former aspect, save that instead of one vast continuous tract of aoe land, there are small narrow plains intersecting gently-undulating owns. ** A bed of coal, ten feet in thickness, is said to crop out on the bank of a stream inland of Timaru. Specimens were obtained from this locality by Mr. Torlesse ; it resembled the lignite from Mount Grey, but was more bituminous. “Striking from the coast across a plain about four miles wide, forming the north point of the Waitaki valley, we reached Te Mo- rokura. The river, a torrent with a freshet channel half a mile in width, cuts through the gravel of the plain, which in the river-bed is intermingled with basaltic and porphyritic pebbles, brought down from the interior of the country by the stream. On the south side the plain is bounded by the Pukehuri range, a spur from the Southern Alps, about 1000 feet high, composed of highly-inclined strata of slate, covered by a ferruginous conglomerate of quartz pebbles. “In Awaamoko, the next transverse gulley west of Waikoura, I observed beds of slate with veins of quartz, dipping south 70°; but I could not, in my rapid passage, make out the relative position of these slates and the quartz conglomerate in the next valley, east of Waikoura, by which we left the Waitaki plain. “Beyond Morokura the country of Waiareka commences, and strata of a yellow and fawn-coloured limestone appear, and continue to Kakaunui. This limestone is generally friable and porous ; it al- most wholly consists of shells and corals, and contains terebratulee, echinites, a species of pseudo-belemnite, teeth of sharks, &c. A microscopical examination shows that the calcareous cementing ma- terial of the larger shells and corals is made up of Textularize, Ro- taliz, and other common genera of Foraminifera, as will be particu- larized in the sequel. “The beds are gently inclined and in various directions ; a section north and south at the low caves at Te Anaamatara, where the last traces of these deposits were visible, showed a slight dip to the north. Fig. 2.—Caves in the Limestone at Te Anaamatara. sss Caves. Lower caves rinesene MIE, y YY HH HL sie in. “This limestone, both at Ototara and Te Anaamatara, is very ca- vernous ; and two large caves at the former place afforded a comfort- able night’s lodging to myself and my companion, Mr. Alfred Wills, and our party ; and it was no small gratification to me to collect from the walls of our cavern the next morning, terebratule, shark teeth, and other fossils, which, if not identical with, seem closely allied to, those I used to obtain, when a lad, from the chalk near Chi- chester ; and which now seeing again for the first time since I left England nine years ago, appeared like old familiar faces greeting me from the rocks of the Antipodes. ——_———— —— === ae 324 PROCEEDINGS OF THE GEOLOGICAL sociETy. [Feb. 27, “Thad no opportunity of ascertaining the relative position of this formation, and the voleanic grit of Kakaunui: the latter on the coast is exposed to the height of eight or ten feet, and dips to the south at a considerable angle ; it contains a great variety of crystalline volcanic products, as hornblende, augite, garnets, &c. It is covered uncon- formably by the usual diluvial beds of gravel and clay, as in the an- nexed sketch. Fig. 3.—Section of the Coast at Kakaunut. ; “<= Diluvial gravel, consisting chiefly of quartz, trap, . OS Circumference of proximal end ............ 4; 0 32) 4,2 Ungueal: length.......ssssesees.ssssececeeees 2.4.70 Circumference of proximal end ............ SPA: Total length ......... 9 4 i Sa The length of the toes when the bones are in close contiguity is about one inch less than the above measurements. The transverse diameter of the expanse of the foot from the distal end of the outer toe to that of the mmer one is 15 inches. From the back of the trochlear extremity of the tarso-metatarsal to the extremity of the middle toe, 13 inches. If to the actual measurements of the bones be added the propor- tional thickness of the cartilagmous coverings of the joints, and the callous integuments, the length of the foot of the living bird may be 1850.] MANTELL ON THE GEOLOGY OF NEW ZEALAND. 339 estimated at 16 inches, and the width of its imprint at 17 or 18 inches. According to the scale of proportions given by Professor Owen in the Zoological Transactions, the corresponding tibia of the tarso-meta- tarsal above described would be about 2 feet 9 inches, and the femur 142 inches in length ; the total height of the living bird about 10 feet. The larger tibize and metatarsais must have belonged to a bird yet more gigantic ; and there is reason to conclude that some individuals attamed a height of 11 or 12 feet, or one-third higher than the tallest Ostrich. I may add, that the height of some of the other species has been estimated by Professor Owen as follow :— Palapteryx ingens, 9 feet. Dinornis struthioides, 7 feet; the height of an Ostrich of moderate size. dromioides, 5 feet, or that of the Emu. didiformis, 4 feet, or intermediate between the Cassowary and the Dodo. The largest Ornithichnite or fossil footmark in the sandstone of Connecticut, would be surpassed in size by the imprint of the foot of the most colossal Dinornis. Phalangeal bones.—Among the numerous phalangeal bones belong- ing to birds of various species and ages, there are a few which do not present the characters of the Dinornis, but evidently belong to other genera. Among these are several which are relatively flatter and shorter, and somewhat resemble those of the Emu; and there are a few middie proximals in which the trochlear articulation is as un- equally divided as in the Ostrich, suggesting the idea that didactyle or two-toed struthious birds may have inhabited New Zealand, con- temporaneously with the colossal tridactyle Moa, and tetradactyle Apteryx and Palapteryx. Lgg-shelis.—Of the egg-shell of the Moa, a few small portions, and one fragment 4 inches long and 2 wide, from Waingongoro, are the only additional examples. The sculpturings on the outer surface of the shells are of three distinct types, and unlike any recent eggs with which I have been able to compare them; they approach nearest to those of the Emu. Some burnt fragments of egg-shells, evidently charred when recent, were found in the ancient fire-heaps mentioned in my former paper, intermingled with roasted bones of dogs, Moas, and men. This fact tends to confirm the opinion that the Dinornis existed when cannibalism was practised by the aborigines of New Zealand. The present collection has also established the interesting fact, that the Apteryx australis, the only known existing type of the Struthio- nidze of these islands, was coeval with the more gigantic species of Dinornis and Palapteryx ; the bones in my possession leave no doubt on that point. We have likewise evidence that the yellow-billed Al- batros, and some species of Penguin, Water-rail, Teal, and Nestor, were comprised in that ancient ornithic fauna. The only terrestrial qua- 340 PROCEEDINGS OF THE GEOLOGICAL socieTy. | [Feb. 27, druped of which there are vestiges in the bone-deposits is a Dog; whether an extinct or living species is not determined. eee Summary.—From the facts described, it appears that in the Middle Island of New Zealand, as in the North Island, the fundamental rocks are metamorphic schists and clay-slate, with dikes of greenstone and compact and amygdaloidal basalt, and intruded masses of obsidian, vesicular and trachytic lavas, and other igneous products. Hornblende and porphyritic rocks, gneiss and serpentine occur, but granite has not been observed. The lofty mountain ranges of schistose metamorphic rocks that ex- tend through the country, from near Cloudy Bay on the north-east to near the south-western extremity of the island, a distance of be- tween 300 and 400 miles, and whose crests everywhere attain an ele- vation above the line of perpetual snow—hence they were called by Captain Cook “The Southern Alps” —are flanked by volcanic grits, and covered at their base by alluvial deposits, which have evidently originated from the decay of trachytes and earthy lavas, and the detri- tus of the harder materials which entered into their composition. No active voleanos are known in the Middle Island, nor have any extinct craters been discovered ; but as the physical structure of the interior of the country, and especially of the Alpine districts, has been but par- tially explored, no conclusive inferences can be drawn from this nega- tive evidence. Strata of limestone, composed of organisms similar to those which prevail in certain cretaceous beds of Europe, crop out in a few localities on the eastern coast, from near Morakura to Kakaunui; but their relation to the adjacent igneous and metamorphic rocks has not been ascertained. A pleistecene or newer tertiary formation—the clay of Onekakara —abounding in shells of species existng in the neighbouring sea, overlies the limestone, and is in many places covered by the alluvial deposits of gravel, sand, conglomerate, and loam, which form the su- perficial soil of the vast plains that are spread over the eastern side of the central mountain chain. On the western shore of the North Island, argillaceous strata with similar fossil shells appear at Wanganui, Waingongoro, &c.; in both islands these beds are from a few feet to 20 or 30 feet above the sea- level. A subsidence of the land to the depth of 40 feet would unite these outliers of a deposit, evidently once continuous ; we may there- fore conclude that an elevation to that extent has taken place since the deposition of the uppermost beds of the blue clay of Onekakara. This phenomenon accords with the horizontal sediments containing drift wood that occur along the coast, and with the terraces of bould- ers of trap, 50 feet high, and the lines of ancient sea-margins now far above the highest tides ; and these mutations in the relative level of the sea and land must have taken place long since the Pacific was inhabited by the existmg species of mollusca. The infusorial earths show that deposits wholly composed of the 1850.] MANTELL ON THE GEOLOGY OF NEW ZEALAND. J41 durable remains of the most minute structures have been in as rapid progress of formation at the Antipodes, as in Europe and America ; and that among many familiar types there are, even in this “imvi- sible world of beg,” unknown forms of animal and vegetable ex- istence. ’ Lastly, the position of the Moa-bed at Waikouaiti has been cor- rectly determined ; like that of Waingongoro in the North Island, it is superimposed on the tertiary clay. Both these ossiferous deposits, though but of yesterday in geological history, are of immense anti- quity in relation to the human inhabitants of the country. I believe that ages ere the advent of the Maoris, New Zealand was densely peopled by the stupendous bipeds whose fossil remains are the sole indications of their former existence. The extreme freshness of the bones in no respect militates against this supposition, for many of the skeletons of the most ancient ex- tinct mammalia in Europe and America have undergone as little change as the specimens before us. Thus Mr. Darwin remarks on the fossil mammalia of the Pampas: ‘As far as I am aware, not one of these animals perished, as was formerly supposed, in the marshes or muddy river-beds of the present land; their bones have simply been exposed by the streams intersecting the subaqueous deposit in which they were originally imbedded. The bones of the head (of the Toxodon) are so fresh, that they contain a large per-centage of animal matter, and when placed ina spirit-lamp burn with a bright flame*.” And Sir Charles Lyell, in commenting on the discovery of the skele- ton of the Mastodon giganteus dug up at Newburgh, observes, “‘ No- thing is more remarkable than the large proportion of animal matter in the tusks, teeth, and bones of many of these extinct mammalia, amounting in some cases to 27 per cent. ; so that when all the earthy ingredients are removed by acids, the form remains as perfect as in a recent bone subjected to the same process. It would be rash to infer from such data that these quadrupeds were mired at periods more modern than the fossil elephants found imbedded in similar clayey deposits in Europe.” From the great numbers of the largest species of Dinornis that must formerly have existed, and the remarkable form and strength of _ their thighs, legs, and feet, constituting powerful locomotive limbs, well-adapted for traversing extensive plains, it seems probable that these stupendous terrestrial birds were not anciently confined within the narrow limits of modern New Zealand, but ranged over a vast continent, that is now submerged, and of which the Isles of the Pa- cific are the culminating points. That the last of the species was exterminated by human agency, like the Dodo and Solitaire of the Mauritius, and the gigantic Elk of Ireland, there can be but little doubt ; but ere Man began the work of destruction, it is not unphilosophical to assume that physical re- volutions, inducing great changes in the relative distribution of the land and water in the South Pacific Ocean, may have so circumscribed * Journal of a Naturalist, Edit. 1845, p. 155. T Sir C. Lyell’s Travels in the United States, vol. ii. p. 265. 342 PROCEEDINGS OF THE GEOLOGICAL society. [Feb. 27, the geographical limits of the Dinornis and Palapteryx, as to produce conditions that tended to diminish their numbers, preparatory to their final annihilation. Of the law which determines the extinction of races of highly or- ganized beings, and whose effects through countless ages Palzeonto- logy has in part revealed, we are as utterly ignorant as of that which governs the first appearance of the minutest livmg animalcule which the most powerful microscope enables us to descry :—both are veiled in inscrutable mystery,—the results only are within the scope of our finite comprehension. I have thus endeavoured to present a general idea of the facts and inferences suggested by the collection of minerals and fossils, and the notes and sketches, communicated by my eldest son, in the hope that his attempts to illustrate the Paleeontology of his adopted country, will be received by the Geological Society as an earnest of his anxious desire to advance, in however humble a degree, our knowledge of the ancient physical history of the earth and its inhabitants. EXPLANATION OF THE PLATES. PLATE XXVIII. Fig. 1. Tooth of Lamma, nat. SiZe............eceeeceneeeeeseeueeteecenseens a] Figs. 2, 3. Terebratula Gualteri, n. sp., Nat. SIZC..........-eeceeeeeeen Fig. 4. Cereopora Ototara, 1. Sp., MAgn.......ceeeeeserecseeeeceeoeeenees Fig. 5. Cereopora Ototara, magn. 2 diam. ..........ssseseeeeeeeenecnees F h Fig. 6. Cereopora Ototara, transverse section of the stem, nat. size | pia ee Fig. 7. Cereopora Ototara, transverse section of the stem, magn. .. Bees Fig. 8. Portion of Eschara, incrusting the upper part of fig. 4, magn. Figs. 9-11. Cereopora, rat. SIZC .......eesesteessserecsceeenccecseeesenes Figs. 12, 13. Mamon, nat. SiZ@ ......sescesesseseeneeecneeeseeeneneerseneees Fig. 14. Manon, magn .........ccssecsecssecencseeetsceseeesereseesonscewees J Fig. 15. Dentaliwm, nat. Size......6.+.-secereeerseeeeeeeeceseereensenceeenes Figs. 16, 17. Turritella rosea, nat. SIZE .........seeeeeeeneeseeseeeeerees ] From the Figs. 18, 19. Turbinolig? at. SiZ€ ....c0.cseceeesessseeeeeeceeeesereeeees blue clay of Fig. 20. Pustulopora Zealandica, n. sp., Nat. SIZE ...c..e sees eeeeeeeee f Onekakara. Fig. 21. Pustulopora Zealandica, magn. 3 diatti. ..+...eee.ssseceeeess J limestone. PLATE XXIX. [In this plate the objects are figured as seen by transmitted light, under magni- fying powers of from 200 to 300 diameters. ] Fig, 1. Teatularia ....ccccssccsccesecnsenseceeceneeseceeeeasensecaesenecaesens From the Fig. 2. J. elongata, 1. Spo ..ccseecsecereteseeeescneesateesnncesecseetennecs | Ototara Fig. 3. 7. acicudata ..1.cccccseeeeseecnteeseseetececsaneeetccaecseeesanees limestone. Figs. 4, 5. Stawroneis Zealandica, 0. SP. ...ssecsecseersersersereeeeeeeees Fig. 5. Stauronets Zealandica, the central bar, detached from the SINTON ick. « asic pins opis io lato ana.cnie sonia «(signee eee emer eek o. 1* Brom the Figs. 6, 7. Surrirella .....ccscececcecssccnecestecasessteeeseeeeneecuseeeenens t infusorial Fig. 8. Pimnularia ........c.cceeescee eee eneee cess cance nneesa teen eee cenenee seas { marl of New Fig. 9. Actinocyclus .....cccceseccssnceeescessencssseneeanecerancecaterecaees | Plymouth. Fig. 10. Pyxidicula .2....ecccceceseccceneeceseeeneeneaecseeeeeecauereraes Fig. 11. Polycystina ..ccccccssecscecceennnnetesceesnerensseessaeeteetsennaes | Fig. 12. Spicule of Gorgonia .....:..+45:. vereertseseceesssFrom the Ototara limestone. ~ Quart. Journ Geol.Soc Vol VI Pl XAVITL = als BPOSSINS FROM NEW ZEALAND COLLECTED BY WALTER MANTELL, ESQ. 1848. Ja3Monnssy, del Dinkel. hel A Hatten Gerden QuartJourn Geol. Soc Vol VI. PLXXIX. FOSSILS FROM NEW ZEALAND COLLECTED BY WALTER MANTELL, ESQ. 1648. In* Mounsey, del 2 Dinkel ith, ‘ord & George, Lithographers, 54,Uacton Garden. 1850.| MANTELL ON THE GEOLOGY OF NEW ZEALAND. 343 Note on Fosstuirerovs Deposits in the MippuE Istanp of NEw ZEALAND. By Prof. E. Forszs, F.R.S. Mr. Hugh Cuming, the eminent conchologist, has lately received from Mr. F. Manse a small collection of fossils from two localities in the Middle Island of New Zealand. Though in a very bad state of preservation, they are sufficiently perfect to enable us to determine the genera, and to pronounce whether or not they are identical with or different from known New Zealand fossils, or animals now existing in the neighbouring seas. The one locality is at Banks’ river. The fossils are imbedded in a greenish grey sandstone. They consist of shells of the genera Sole- curtus, one species; Tellina, one species; Lucina, three species ; Cardita, one species; Artemis, one species; Pectunculus, one spe- cies; Crenella? one large species; Modiola, coated with Membrani- pora; Turritella, one species very abundant; Calyptra@a, one spe- cies; and Tvochus, one species. The other locality is at the cliffs of Blmd Bay. The fossils are imbedded in a greenish conglomerate of small pebbles. They con- sist of a Lucina, a large species of Arca, a Cardita distinct from that at Banks’ river; one species of each of the following genera, Turbo, Fusus’ Acmea, Bulla, Tornatella? and a Haliotis-like shell; also two fragmentary corals, apparently belonging to the genera Turbinolia and Dendrophyllia. None of the fossils in either locality can be identified with any re- cent species. Their general aspect recalls very strongly that of eocene shells from the Bognor beds. The specimens have been presented by Mr. Cuming to the Museum of Practical Geology. 344, DONATIONS TO THE LIBRARY OF THE GEOLOGICAL SOCIETY, January \st to March 31st, 1830. I. TRANSACTIONS AND JOURNALS. Presented by the respective Societies and Editors. ACADEMIE Royale des Sciences de Paris, Comptes Rendus de I’. Tome xxix. nos. 15-27. Deux. Série, and tome xxx. nos. 1-6. Agricultural Society of England (Royal), Journal. Vol. x. part 2. no. 24. American Academy of Arts and Sciences, Memoirs. New Series, vol. iv. part 1. Journal of Science. Second Series, vol. ix. no. 25. Atheneum Journal. Berwickshire Naturalists’ Club, Annual Address, 1849. Calcutta Journal of Natural History. Vol.i. From Sir R. I. Mur- chison, V.P.G.S. Cambridge Philosophical Society, Transactions. Vol. viii. parts 1-5. Dublin Geological Society, Journal. Vol. iv. part 2; and List 1849. France, Société Géologique de, Mémoires. Deux. Série, tome iii. partie 2.—Bulletin. Deux. Série, tome vi. f. 34-43 ; tome vii. f. 1-3. Geographical Society (Royal), Journal. Vol. xix. part 2. Geological Society of London, Transactions. Vel. u. First Series, and vol. ii. part 1. Second Series. From the Royal Institution. Indian Archipelago, Journal. Vol. i. nos. 10, 11, and 12. Linnzean Society, Proceedings. Nos. 34-40. List 1849, and Charter and Bye-Laws, 1848. Milano, Imp. R. Instituto Lombardo di Scienze in, Memorie. Tomo i. and il. DONATIONS, 345 Milan. Giornale, Biblioteca Italiana. Nuova Serie, tomo i. fas. 1-6. Giornale. Tomo 1-8. Memoria del Signor Francesco Meguscher 1 Boschi dell’ alta Lombardia. Normandie, Société Linnéenne de, Mémoires. Vols. i.—viii., and Atlas 1825. Rapport Iu dans la Séance du 5 Nov. 1849, Sur un Mé- téore, par M. Leboucher. Séance Publique, 1837. Procés-Verbal des Séances de l’Institut des Provinces, tenues 4 Caen en Oct. 1846. Note sur une téte de Croccdilien Fossile récemment décou- verte aux environs de Caen, par M. E. Deslongchamps. —— Annuaire de I’ Institut des Provinces et des Congrés Sci- entifiques, 1850. Institut des Provinces de France. Exposition Régionale de Peinture, Sculpture, &c., pour le centre de la France, 1849. Paris, P Ecole des Mines, Annales. Quatriéme Série, tome xiii. liv. 3; tome xiv.; tome xv.; tome xvi. liv. 4. Philosophical Magazine. From R. Taylor, Esq., F.G.S. Scarborough Philosophical Society, 18th Annual Report. Stockholm, Kongl. Vetenskaps-Akademiens Handlingar for 1847 and 1848. meee Ofversigt af Kongl. 1848. St. Pétersbourg, Académie Impériale des Sciences de, Mémoires. Tome vi. liv. 3, 5 & 6. — Bulletin de la Classe Physico-Mathématique, tome vii. II. GEOLOGICAL AND MISCELLANEOUS BOOKS. Names in italics presented by Authors. Delesse, Achille. Various Memoirs extracted from the Bulletin of the Geological Society of France, &e. Descloizeaux, A. Observations Physiques et Géologiques sur les principaux Geysirs d’Islande. From Sir R. I. Murchison, VEE.G.S. Deville, Ch. Sainte-Claire. Recherches sur les principaux Phéno- meénes de Météorologie et de Physique Générale aux Antilles. —. Voyage Géologique aux Antilles et aux Iles de Ténériffe et de Zogo. Etudes Géologiques, 3 liv. D Orbigny, Alcide. Prodrome de Paléontologie Stratigraphique Universelle des Animaux Mollusques et Rayonnés. Vol. i. 346 DONATIONS. Gray, James. The Earth’s Antiquity in Harmony with the Mosaic Record of Creation. From Mrs. Buckland. 2nd Copy, from the Author. Helmersen, G. von. Herrn von Middendorff’s Geognostische Beo- bachtungen auf seiner Reise durch Sibirien, B. I. Th.I. From Sir R. I. Murchison, V.P.G.S. Iubbock, Sir J. W. Onthe Theory of the Moon and on the Per- turbations of the Planets. Part 8. Morton, 8S. G., M.D. Additional Observations on a new living species of Hippopotamus, of Western Africa. Pareto, Marchese L. Osservazioni Geologiche dal Monte Amiata a Roma. From Sir R. I. Murchison, V.P.G.S. Discorsi del, Presidente della Sezione di Geologia e Mi- neralogia all’ ottavo Congresso Scientifico Italiano letti alle Adu- nanze dei Giorni 15 e 28 Sep. 1846. From ‘Sir R. I. Murchi- son, V.P.G.S. Pilla, L. Osservazioni Geognostiche da Napolia Vienna. From Sir R. I. Murchison, V.P.G.S. Reeve, Lovell. Conchologia Iconica. Monograph of the Genus Bulimus. St. John, John R. A true description of the Lake Superior Country. From the Rev. T. Hincks, LL.D., Hon. M.G.S. Taylor, Walton and Maberley. Two descriptive Catalogues of Works published by, 1850. Thurmann, Jules. Essai de Phytostatique appliqué 4 la Chaine du Jura, &e. Tomei. & ii. Yandell, L. P., M.D., and B. F. Shumard, M.D. Contributions to the Geology of Kentucky. From Dr. G. A. Mantell, F.G.S. THE QUARTERLY JOURNAL OF THE GEOLOGICAL SOCIETY OF LONDON. PROCEEDINGS OF THE GEOLOGICAL SOCIETY. Marcu 13, 1850. Henry Hussey Vivian, Esq., and Henry Smith, Esq., C.E., were elected Fellows. The following communications were read :— 1. On the MetTamMorpuic and MeTALuirerovs Rocks of EAsTERN Nova Scotia. By J. W. Dawson, Esq. [Communicated by the President. } In those parts of Nova Scotia lying eastward of the Shubenacadie River, and northward of Mines Basin and Channel, about half of the surface is occupied by carboniferous beds, whose arrangement has been noticed in various papers communicated to this Society*. The remainder, with the exception of a few small patches of new red sandstone and unaltered Silurian strata, consists of metamorphic rocks, for the most part older than the carboniferous system. These metamorphic rocks may, by evidence derived from mineral characters, geographical distribution, and associated fossiliferous beds, be divided * Proceed. Geol. Soc. vol. iii. p. 711 (Mr. Logan) ; vol. iv. p. 124 (the Presi- dent’s Address) ; p. 184 (Sir C. Lyell); p. 186 with map (Dr. Gesner). Quart. Journ. Geol. Soc. vol. i. p. 26 with map (Mr. Dawson); p. 322 with map (Mr. Dawson); p. 393 (Sir C. Lyell); vol. ii. p. 133, organic remains (Mr. Dawson and Mr. C. Bunbury); vol. iv. p. 50 with map (Mr. Dawson); vol. v. p. 129 (Dr. Gesner). VOL. VI.—PART I. 2c “> 348 PROCEEDINGS OF THE GEOLOGICAL sociETy. [March 13, into two great groups, which, so far as I am aware, have not hitherto been accurately distinguished by writers on the geology of Nova Scotia. In the present paper I propose to notice the composition, arrangement, and distinctive characters of these groups; and to describe, somewhat in detail, the metalliferous veins which have been discovered in one of them. I. One of these metamorphic groups is, in the part of the province now under consideration, limited to the Atlantic coast and its vicinity. The prevailing stratified rocks in this group are, compact and flaggy grey quartzite (often weathering white), mica slate, and clay slate; the latter usually of dark colours, and occasionally passing into flinty slate and quartzite. These rocks usually occur in beds of great thickness. The hypogene rocks associated with them are white and flesh-coloured granite, which has penetrated the metamorphic rocks in large irregular bands and masses. The white granite, which is the most abundant, has white potash felspar, translucent slightly purplish quartz, and grey and black mica. I am not aware that any workable metallic deposits have been found in this group, or that any fossil remains are contained in it. As the association with granite is a somewhat characteristic feature, this group may, for the purposes of this paper, be named the granitic group of metamorphic rocks. It must not however be confounded with the granitic group of Dr. Gesner’s arrangement*, which consists exclusively of hypogene rocks, and includes syenite, porphyry, and trap, belonging in my opinion to a different system. The granitic group forms a continuous, or nearly continuous belt along the Atlantic coast of the province, narrow at its north-eastern extremity, and apparently attaining its greatest development im the western counties. In the part of the province now under considera- tion, its southern or coast side has a general direction of S. 68° W. ; its inland side, though presenting some broad undulations, has a general direction of about 8. 80° W. Its extreme breadth at Cape Canseau, its north-eastern extremity, where it is bounded on one side by the ocean, and on the other by Chedabucto Bay, is only about eight miles. In its extension westward, it gradually increases in width, until at the head of the west branch of the St. Mary’s River, eighty miles distant from Cape Canseau, it is about thirty miles in breadth. Westward of this point, it does not increase in breadth within the district to which this paper refers. In the peninsula of Cape Canseau, mica slate is very abundant and presents many beautiful varieties}; it is associated with quartzite, clay slate, and granite. At the St. Mary’s River, the northern side of the belt consists of a great thickness of grey quartzite, often flagey and micaceous, and occasionally intersected by veins of white quartz. In the centre of the belt great masses of granite appear at a little distance from the river section, and nearer the coast, mica slate and * Industrial Resources of Nova Scotia, p. 232. + [am indebted to Mr. Whiteman, of the Railroad Survey, for an interesting suite of specimens from this peninsula. 349 1850.]| DAWSON—METAMORPHIC ROCKS OF NOVA SCOTIA. ‘IDANT JLOqoponbsnyy * *IOATY SATB “1S JO Yourlg yey * IIATY 8 ALVA “FS JO YouvIg ISOAA ° TOATY S Arey 4S ° ‘IOATY UOWTeS ‘neasueg adeg - “Avg ojonqepsyO ° ‘auidnoiog odep ° *neasuey jo ny ‘EG ° ‘ayeT Joqeyoo7yT “1OATY WIMOG * ‘ystuoSsyny ° "931095 ‘1g adeg ° ‘DAO JUCUSITeYL * ‘Sresuy ° "IIA S ,AouIeg * “MogieyyT YsMoswayy * NOI ° “TOA YSVq * “TOATY OTPPLAL * *IOATY ISOM ° "MOLT, JUNOT * ‘TOA WOWyes ° *suleyUNOy, prnbaqog °g ° *IOATY DOVTTEAA ° ‘9 ac a4 a xd “IOAN VSUTIIA FVII) ‘Toaryy ATION *IOATY OOVIMIIS "LIAN OIpvovuaqnys “Spuvls] OAT WY, ‘UISeg SOUT ‘7 T ‘jauuLyD soul ‘T *QUOISPUBS Poy MINT *SNOLaJIMOGIeD op diomejour-on1uesg “OIG AALOUIVOUL-I1}IUBIY) ec it SG x yi IS , 1 g \h=< « i it KU a cs es | “SOTIU 99N4VIg OF “O[BIG 276.2 ‘bs ‘NOSMVG “Mf AG “VILOOS VAON AO LUVd dV 'TvVOIDO'IOAD 396 Section from the Mouth of St. Mary’s River to the Mouth of Barney’s River.—Distance 50 miles. Fig. 2. PROCEEDINGS OF THE GEOLOGICAL socrEeTy. [March 13, Atlantic. nj A) ° A Bees LU [= irs} FB Se ey 28 g cS he ca Sy S SMM Aes “ er i as} Granite. Ane ii Ch M oga it Pa fl ti WM alan 7 Pop Lilie LL! y, extending along West Branch of St. Mary’s River. metamorphic band of Atlantic coast. Yh SE rr a et cc Ac Uf, Quartzite. » d. Granitic- ~y (op c. Carboniferous valle Sandstone, shale, and conglomerate. Quartzite and slate o =) a vo a 7) ‘aqtuatc ‘ayes pue 371ZIeN% Sandstone and conglomerate. Ww. a. Lower carboniferous beds of the eastern extremity of the Pictou carboniferous district. 6. Syenitic-metamorphic district of Merigomish Hills and East Branch of St. Mary’s River. N Gulf of St. Lawrence. quartzite prevail. Westward of the main stream of the St. Mary’s River, clay slate and quartzite with masses of granite are the pre- vailing rocks. The surface of this metamorphic belt is rugged and uneven, but not very elevated. The inland side is however somewhat higher than the parts nearer the coast, attammg in some places an elevation of about 600 feet ; it abounds in small lakes and streams, and its coast line is much indented. From the upper part of the west branch of the St. Mary’s River to the head of Cheda- bucto Bay, the granitic group is bounded on the north by a valley occupied by sandstones, conglomerate, and shale, composed of the de- bris of the hypogene and metamorphic rocks ; and containmg a few Calamites and other fossil plants of the carboniferous system. This belt of carboniferous strata, which I explored and marked on the map of the province for the first time in 1845, separates in its whole length the granitic group from that next to be described. (See Section, fig. 2.) II. In the second, as in the first metamor- phic group, the prevailing rocks are slate and quartzite ; these are, however, of much more varied characters. The former varies from greywacke to imperfect micaceous and taleose schists through many intermediate varieties of clay slate, and presents grey, olive, black and reddish colours. The latter is of every variety of texture, and ranges in colour from white to dark grey. These rocks are also more thinly bedded, and present more fre- quent alternations than those of the granitic group; at some points they are observed to pass into less altered rocks, containing organic remains; and in several localities they are traversed by metalliferous vems. The igneous rocks which have penetrated the strata of this group are very abundant, and exceedingly varied in their composition and characters. Their prevailing composition is felspatho- hornblendic, a character by which they are in general markedly distinguished from those of the granitic group. Syenite, greenstone of many varieties, compact felspar, claystone, and porphyries with bases of the two latter substances, are the most common of these ore - 2 POT Pld. ------><- - GTANUE, JWMSS and w varerety Lypaguira west of Bogotw. Yo, Sall, 100 feet theck wedge like A Ls _ ‘covered bv gypsune £ sup— X} ported by the carboniyerous a z Sands t, *9U0IS = -Sey snovoqyis Jo & spaq ygta ‘seq * -qod pure spurs TTOOTAUECOOO CEE OPIATE se fo) 5 5 5 *keyo oS puowuy UTC UTE TL —— EPRI FG LETT R ELUATE NTE *9UOJSpuUes jo swuvos Areuoya19u09 “feyo p10}xO 'N } 464 PROCEEDINGS OF THE GEOLOGICAL society. [June 19, the surface which it occupies over the tract which intervenes between Bourton and the escarpment of the chalk : it is an isolated mass, from about which the upper beds of the Kimmeridge clay have been par- tially removed on every side ; nor do any like beds occur at the base of the cretaceous series, where the gault rests directly on Kimmeridge | clay. § 2. Swinpon. On the following morning we commenced with the great quarry west of the town. The mass dips away at a small angle east and south, so that the lowest beds are exhibited on the west and north. At the north-eastern corner of the quarry the succession from below upwards is as follows :— 1.. Thin seam of black pebbles, of which a portion is always to be seen attached to the lowest masses of sandstone. Stratified sandstone, thin-bedded, pale blue: 5 feet. Clay, containing a bed of Ostrea falcata, Sow., Perna quadrata, Sow. : 1-2 feet. Sands and. sandstones, 25 feet; the lowest portion most fossi- liferous. Cardium dissimile, Sow. 5. Calcareous sand, passing up into pure limestone, 5 feet ; contain- ing a bed about 1 foot thick almost entirely composed of Tere- bra Portlandica, Sow. 6. Above this marine limestone, but not separated by any line more distinct than is usual in stratified limestone masses, is a limestone . offermg some slight differences in appearance and fracture, but containing apparently only freshwater forms. Above this are bands of clays and calcareous sandstones. The whole constituting the freshwater portion of the series. 7. Thin-bedded calcareous sandstones, with marine shells, in a mass of sand, forming the highest portion of the Portland series. Above the surface of the beds of Swindon Hill is a considerable capping of drifted materials, resting on an uneven surface, containing materials of various geological ages, and in no way connected with the history of the beds below. The geological pheenomena which this quarry presents are of ex- ceeding interest, and it will be perhaps the most intelligible course we can adopt, in order to make them appreciable, if, mstead of a dry mineralogical account of admeasurements, we explain briefly the suc- cessive conditions which are indicated at this spot, over an area of fifteen acres. _ 1st. At a place in the oolitic sea, where the deep-sea mud-bed of the Kimmeridge clay was being deposited, there is evidence of a sudden increase in the: moving power of the water, of the dis- turbance of the materials of the zone of subangular pebbles, and of their outward dispersion. The deposits which immediately follow are of fine clean siliceous sand, or at times with a slight proportion of calcareous matter: the change here indicated is that of a diminution of depth at this spot ; or, what will describe the change more accu- rately (the sea-level being supposed uniform), a rise proceeding from the land-side of this portion of the oolitic sea. ene 1850.] AUSTEN—SANDS AND GRAVELS OF FARRINGDON. 465 Dr. Fitton notices a Portland sand as a separable group from the Portland stone at this place ; and as it appears to us, most unneces- sarily : the whole of the lower portion of the mass which succeeds the Kimmeridge clay is arenaceous, of which the building-stone _ constitutes subordinate bands. After an accumulation of about five feet of sands had taken place, the conditions of sea-bed favoured the development of a great bank of the Ostrea falcata, Sow., and Perna quadrata, Sow.; the bed is from one to two feet thick, com- posed to a great extent by these two forms alone, with fine sedi- mentary matter in layers. Sands, now mostly passed to the condi- tion of sandstone, succeeded, and which for the first few feet are re- markably rich in the usual fossils of the Portland (Trigonia clavellata, Park., Cardium dissimile, Sow., which here attains a great size). Throughout the remaining portion of the sands and sandstones fossil remains are comparatively scarce, with the exception of Ammonites, which occur irregularly. The grain or line of deposition of the building-stone masses accords with the bedding, whilst the arrange- ment of the imtervening sands is mostly diagonal. The particles composing the stone are finer than those of the sands, and they con- tain a proportion of lime; the difference is due in the first instance to a varying moving power of the water. In the calcareous beds of the Swindon Portland, organic remains again become abundant, and certain new forms predominate, such as the Terebra Portlandica, Sow., which alone forms a band of some thickness near the base of the pure limestone portion. The limestone mass, when its lower portion is compared with its upper, presents a slight mineral change, which hardly admits of bemg described, but which is perceptible on the spot—and this change is found to correspond with the condition of the mass of water under which it was deposited—the lowest portion is marine, the forms in the upper are those of fresh water. The only feature which at all indicates a change of condition of the water is the gradual decrease of the forms so abundant in the lower portion of the limestone ; there is no passage through brackish water forms, nor any break to show an interval of time, or a change from sea-bed to that of a lake, but simply such a change as would be the result of the influx of a mass of fresh water into the oolitic sea, bringing with it its own peculiar forms, and thus rendering a given area objectionable to marine ones. The diminished size of the Cardiwm may perhaps be taken as an in- dication of such a change in the condition of the water, and the small Ostree which occur within the mass containmg Cyclas? and Cypris would clearly show that the calcareous beds still belonged to the area of the oolitic sea. At a time subsequent to the first indications of this change of con- dition the limestone mass has been greatly disturbed, great blocks have been detached, and rolled about on the surface of the mass, and these are often eaten out by some excavating animal, and we must consider these fragmentary beds as having been produced by the ordinary action of the sea, when the mass had been brought up to the condition of a submerged reef, and within the reach of wave-ac- 466 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 19, tion. The higher portions of this part of the series consist of bands of clay, with carbonaceous matter and occasional partings of sandy and calcareous materials, now passed to the state of loose rubbly stone. For a considerable thickness the beds indicate times of tran- quil deposition, of the occasional disturbances of such surface, of no great depth of water, and the proximity of some area of land. If the conditions recorded in the Swindon quarry are to be de- rived from its western side alone, it would seem as if this fragmentary and disturbed portion constituted the close of the series of changes, which followed in the long uniform period indicated by the Kimme- ridge clay. The summit of Swindon Hill forms a tabular surface, and owing to the inclination of the beds, the denudation which has taken place at some period long subsequent, has proceeded to a lower portion of the series on the west to what it has on the east; and (with the exception of a capping of detritus, containing materials of all ages up to the grey-wether-sandstones) the fragmentary and dis- turbed beds form the highest part of the quarry ; the like holds good along the north side of the quarry and part of the eastern, but with the dip of the beds south, these disturbed bands of clays and sands are seen to be surmounted by layers of tranquilly deposited sand- stones in thin layers interstratified with sands, and in these the forms of the marine Portland reappear*. We next examined a quarry about a mile from the town of Swin- don, on the north of the road to Coate: the beds in which it is opened belong to the upper calcareous portion of the Portland, and present a like order in the occurrence of the fossil forms with that already described. The limestone mass seems to be surmounted with thin-bedded sandstone. About a quarter of a mile on the same road, but on the south side, is another large quarry: the beds here dip to the north, which would take them beneath those of the quarry just noticed. The beds are sands and sandstones, which agree very exactly with those of the lower portion of the great quarry close to the town. At Broom Hall the lowest sands and sandstones are seen resting on the Kimmeridge clay, with a band of black subangular pebbles at the line of junction, and incorporated with the lower layers of stone. The last place in this direction at which the Port- land beds are worked is on the east side of the reservoir: here also they belong to the lowest part of the series, resting on Kimmeridge clay, and containing the like admixture of lydian-stone pebbles. The ferruginous sands which surmount the compact sandstones, on the level of Day-house Farm, contain beautifully preserved specimens of Trigonia gibbosa, Sow. The thm Kimmeridge clay, which emerges from beneath this mass of Portland, is continued to the rise of the * Mr. Brodie has given an account of what he designates as the ‘ Purbeck strata” at Swindon (Geol. Journ. vol. iii. p. 53). His section is taken at the western end of the quarry, and represents a thickness of 13 feet. The description given by M. Cornuel of the upper jurassic strata of Vassy agrees well with the series of conditions to be observed at Swindon, the “ Oolite vacuolaire”’ repre- senting mineralogically as well as in its Cyrene, Mytili, and Melanie, the fluvio- marine strata of the top of the Portland. 1850.] AUSTEN—SANDS AND GRAVELS OF FARRINGDON. _ 467 cretaceous escarpment. We were unable to confirm the representa- tion of Dr. Fitton, that the lower greensand occurs at the top of Swindon Hill (p. 265). Day-house Farm is also described as afford- ing the Purbeck, Hastings, and Wealden beds in superposition on the Portland, but we have shown that it is the Jower portion of the Portland only which occurs at that place: the sands which Dr. Fit- ton has represented as lower greensand at this place* (the minera- logical resemblance having probably induced the view), belong to the middle portion of the Portland series, as indicated by Trigonia gibbosa, Sow. The principal point of interest presented by the section along the east side of the great quarry at Swindon, and which, if observed here or elsewhere, has been useless so far as any inference from it is con- cerned, is the fact that the period which is marked by considerable disturbance, by irregular deposits, carbonaceous materials, and fresh- water forms, is overlaid by tranquilly deposited beds of marine sand and sandstone of the Portland series. Dr. Fitton appears to have overlooked the fluvio-marine conditions indicated at the Swindon pits, but it is this higher portion of the Portland series which I imagine he notices at p. 265, and describes as white calciferous sands, with concretions in which are Portland fossils, and occurring at the top of Swindon Hill, and occupying the position of the beds at Dinton, full of Ostree and Mytil, which surmount the alternating series of clays, limestones, and fossil sandstones containing Cyclas and Cypris. I do not propose to enter now on any speculation as to the physical features of the Wealden, particularly as I propose to make the whole body of the evidence we possess as to the nature and extent of its area the subject of a distinct communication. The conditions indi- cated by the series of beds at Swindon, containing freshwater forms, were at no time those of a closed or land-locked area of fresh water, but rather the conditions of a sea contiguous to a body of fresh water, and into which masses of fresh water were discharged. Neither is it necessary here to ascertain the portion of the Wealden group with which the Swindon beds are synchronous; that they are the geological equivalents of some portion is sufficiently clear, and the point which the Swindon section clearly establishes is, that the Wealden is not, as has hitherto been represented, a freshwater accu- mulation of an area of dry land subsequent to the oolitic period, but was contemporaneous with the Portland, and perhaps even with older portions of the oolitic series. The other points which suggest themselves as deserving of notice arise out of a comparison of the two masses of Portland strata at Bourton and Swindon,—the distance which separates them is from six to seven miles. In the lower portions of both occur beds of sub- angular pebbles, which mineralogically are identical, and in all proba- bility derived from the same source. That the dispersion of these pebbles was not due to some momentary disturbance is clear from the thickness of the beds through which the pebbles range at * Loc. cit. Section No. 17, pl. 10a. 468 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 19, Bourton (10 ft.), a thickness which implies a vast lapse of time: conglomerate beds occurring in this way only indicate that the depth of this portion of the oolitic series, at this particular spot, was that of the zone along which subangular pebbles are drifted. The cal- careous portions of the two masses do not differ to any extent worth noticing; and the yellow and buff fine-grained sands, which at Bourton surmount the calcareous oolitic sands, taken together, corre- spond in thickness with the main mass of sands and calcareous sand- stones at Swindon, whilst the uppermost calcareous beds of Bourton would agree in position with the main portion of the limestone, the rest of the series having been removed from above the Bourton mass. It will be seen from this that the Portland beds at Swindon and Bourton are isolated masses of considerable thickness and compact structure, resting on Kimmeridge clay. The surface of the oolite formation may have been eroded at various times, but the effect pro-- duced at one particular period is perfectly distinct from every other. No fact can be more certain than that the sea cannot transport sand and gravel across areas of impalpable deep sea mud, and there pile them up in detached conical masses. So that when we meet with such accumulations as those of Bourton and Swindon, we may feel assured that at some time they formed portions of continuous beds of such materials, and having an extent equal, at least, to the area over which the isolated patches now occur. The fact that these Swindon and Bourton masses of the Portland series rest on Kimme- ridge clay, and that this same clay, at short distances, varymg from half a mile to two miles in breadth, passes beneath the gault, clearly shows that this particular denudation of the Portland had taken place before the earliest beds of the cretaceous series were deposited. § 3. Devizes. It will not be necessary to notice the beds of upper greensand which occur here, as they are well known from the forms which they supplied to the ‘Mimeral Conchology’: they attain a great thickness, are well exhibited in several deep road sections, and are more uni- formly arenaceous than at places to the eastward—a mineralogical change which becomes marked as the upper greensand ranges from east to west. About halfway down the series of rocks at this place, beds of blue clay are exposed in a brick-yard, and which were long since described as “gault”’ by Mr. Lonsdale. The clay descends to the level of the water at the bridge, which would give it a thickness of about 40 feet : just beyond the bridge, beds of thin-bedded sandstone are exposed in the bank of the Canal, and like beds, together with ferruginous bands, were traversed in sinking a well at the residence of the en- gineer, close to the bridge: the ferruginous blocks were very fossi- liferous, containing casts of a smali Nucula in great abundance, drca, Cypricardia, and Emarginula. From the information we received from Mr. Cunningtcn, it would appear that the thickness of this bed of ironstone, sandstone, and 1850.| AUSTEN—SANDS AND GRAVELS OF FARRINGDON. 469 conglomerate must be very trifling, as it occupies only a narrow breadth of land in advance of the ridge of gault clay, and is quickly succeeded by the Kimmeridge clay. At Rowde, and the other places at which we subsequently saw these beds on our way to Calne, they are evidently thicker; and in their general arrangement and composition closely resemble the more ferruginous portions of the Farrmgdon gravel beds, such as those of Fernham. At Stock-Orchard, near Calne, we again saw the ferru- ginous conglomerate resting on the surface of the Kimmeridge clay, and not having any great thickness or continuity, as the Kimmeridge clay had been reached through it, and emerged from beneath it in the south. It is this locality which afforded what is apparently a rare shell in this deposit—the Diceras Lonsdalei, Sow., figured amongst the illustrations to Dr. Fitton’s memoir. No one can reasonably doubt the geological identity of the iron- sand and gravels of Devizes, Rowde, and Calne with those of Far- ringdon. ‘The same specific forms of Nucula, Opis, Emarginula, and Terebratula, connect them one with another. The ferruginous sands and gravels which we have thus identified as of one and the same geological level, on better evidence than was before possessed, are referred by Mr. Conybeare to his group of ‘ Iron- sands,’ an assemblage of deposits grouped together from the circum- stance of presenting a large proportion of iron, and including the ironsands of the Weald, some of the ferruginous portions of the upper greensand, as well as the deposits here in question. ‘lhe im- propriety of classing these several masses together was apparent, when the freshwater origin of the ironsands of the Weald became established. It will be seen by the sections, as well as from the account of the mode of occurrence of these several masses of ferruginous sands, that the line of the Devizes Canal and its vicinity is the only one along which they occur in an intermediate position between the gault and the Kimmeridge clay ; and it was this circumstance I imagine which induced Mr. Lonsdale to refer them to the cretaceous series, whose views were adopted subsequently by Dr. Fitton, The superposition in this case will be presently considered, whilst the amount of fossil evidence, as exhibited in Dr. Fitton’s paper, would hardly admit of the identification of the beds of Rowde and Lockswell Heath with the lower greensand. Geologists who may be disposed to take Mr. Lonsdale’s and Dr. Fitton’s views respecting the cretaceous age of the ferruginous sands and gravels, or, as they had better henceforward be called, the ‘Farringdon beds,’ will naturally lay great stress on the Devizes section: what we have therefore to inquire is, the real value of this particular instance of superposition. It is by no means a necessary consequence, that an arenaceous deposit, because it occurs in an inter- mediate position between the gault and the Kimmeridge clay, should be of the age of the lower greensand : if this sand was the only geo- logical link required to fill up the interval between the two forma- tions, the inference might be allowed ; whereas we know that a vast 470 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 19, lapse of time, hundreds of feet of sedimentary deposits, and altered conditions of the whole of the northern hemisphere, are recorded between those two periods. When we employ the term “lower greensand,’’ we mean only to designate deposits of sands and sandstones, occurring beneath a por- tion of the cretaceous series, and connected with that series, not by any specific identity of its organic forms, but by a certain general resemblance and aspect of its fauna, and by some of its forms being referable to the same divisions and subgeneric groups, as in its Fishes, Cephalopods, and Echinoderms. The lower greensand is not everywhere co-extensive with the cre- taceous series, and where it is wanting the series commences with the gault, the chloritic sands, or even with the lower chalk, as the case may be; but whenever the lower greensand does occur, its re- lation to the gault is invariable—it is beneath the gault*. It is not necessary that we should here enter on an inquiry as to what were the particular submarine conditions which caused the gault clays to overlap the lower greensand in the extension of the cretaceous series westwards ; a process which, in turn, is repeated by the upper green- sand with reference to the gault; but it is clear that so far as each of these divisions extended itself, it must have done so continuously. Such is not at all the condition of the masses of ironsand and gravel in question; the Farrmgdon beds, with a thickness perhaps of 100 feet, rest, as an isolated mass, upon the Kimmeridge clays: at a distance of two miles, the cretaceous series commences with the gault, also resting on Kimmeridge clay. The sands and gravels at Far- ringdon are thicker than at any other place at which we find them, and did they belong to the cretaceous series, as represented by Dr. Fitton, we surely ought to find some traces of them below the gault. The remarks which arose on the subject of the isolated condition of the masses of Portland, at Swindon and Bourton, apply with even greater force to the much thicker accumulations of Farringdon: as in that case, so here, we may feel assured that the beds at Farring- don, Calne, and Devizes, formed part of a continuous zone of deposits, which must have been denuded and reduced to isolated patches before the period of the gault. Unless we can believe that these separate masses severally had not at any time a greater horizontal extent than they have at present, they must have been reduced to their present dimensions before the gault could possibly have been deposited on beds of Kimmeridge clay ; and if at Farringdon a long period of de- nudation and removal of materials separates the ironsands and gravels from the gault, we cannot suppose that they can possibly form toge- ther a continuous and ascending series of deposits at Devizes. The position of the whole of the Farrmgdon mass on the Kim- meridge clay, and zfs perfect independence of the cretaceous series, are facts which rest on the evidence of sections respecting which there is no ambiguity whatever; and we may therefore feel assured that they were subjected to that process of denudation which abraded the * See Dr. Fitton’s Sections, passim. 1850.| AUSTEN—SANDS AND GRAVELS OF FARRINGDON. 471 surface of the oolitic sea-bed prior to the deposition of the gault over Oxfordshire, Berkshire, and Wilts. There are other considerations which warrant the assertion that the superposition of the gault on the ironsands at Devizes is of no value whatever, in the shape of proof of the sequence and connexion of the two deposits. The oolitic deposits in their range mto the South of England gra- dually acquire a north and south direction, and this disposition dates back to a period before the cretaceous, inasmuch as this latter series in its extension westwards overlaps in turn every member of the oolites : the two series may be represented by two converging lines or bands, which at length meet ; but the order of succession pre- sented at such poimt of meeting can no more prove the continuity of the gault with the ironsands as parts of one system of deposits, than it can with any portion of the middle or lower oolites with which it afterwards comes in contact. The position of the gault on the Far- ringdon beds at Devizes is clearly transgressive, and can only show that the latter are not newer than the ganlt (or of the age of the crag), which for anything to be seen at Farringdon might be the case. From what has been here stated, as to the composition and posi- tion of the Farringdon and equivalent beds, it will be easily con- cluded, by some, that they must be either Portland or lower green- sand, and if not one, then certainly the other. One very apparent defect in the geological investigations of the present day, is the disposition to adjust each successive addition of knowledge to a certain artificial scale of formations ; and of this ten- dency geology must free itself, if it would arrive at the true nature of the physical changes with which it is concerned. The artificial scale of formations, which still figures in elementary treatises, more particularly with respect to secondary geology, represents an order of superposition, and lines of separation, which are both untrue, as well with respect to the mineral masses as the forms they contain— the result of the too hasty generalization of local phenomena. The Farringdon beds seem to present an instance of what some of the steps may be in the progress of change from one series of formations to another. If the Farringdon beds were non-fossiliferous, we should arrive at their age by such considerations as these :—that they occur at, and are connected with, the top of the Kimmeridge clay, and that they never occur in any other position—in which respects they coincide with the Portland deposits ; that the lower portions of both consist largely of conglomerates, composed of peculiar materials; that the upper part of the Portland contains indications of a contemporaneous area of fresh water, as apparently the ironsand does at Shotover ; that their denudation was effected before the period of the gault. On these and other common features, each of which is the evidence of distinct physical changes and operations, the which could hardly have taken place in the hke order at two distinct periods of time over the same spot, we should be warranted in considering the Farringdon beds the equivalents of the Portland. I will not however press this 472 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. - [June 19, view in the simple form in which it is here stated; what I would urge is the great importance, in a physical point of view, of the distinct ndependence of the Farrigdon series of deposits, and their total separation from the cretaceous, as parts of a consecutively de- posited group, by the intervention of a vast period of denudation. The process of denudation of any mass of sedimentary deposits to a given depth is probably equally slow, or implies an equal space of time with that which was required for its accumulation ; and it implies too a complete change in the relation of the mass of water (the same agent in both cases) to the sea-bed. No broader lines can possibly be drawn by which to separate masses of old sea-beds, than those which indicate so great an amount of physical change as this ; and bearing always in mind that geology is nothing more than the physical geography of former periods, we must allow to such features a primary importance beyond that of the continuity or first appear- ance of certain specific organic forms: the changes in the suites of such forms, through a series of deposits, are nothing but the conse- quences of new conditions brought about by the ceaseless oscillations of the earth’s surface. Having established, on physical considerations, the complete sepa- ration existing between the Farringdon deposits and those of the nearest portions of the true cretaceous series, it remains for us to inquire into the amount of fossil forms which may serve to connect them. The fossiliferous localities of the Farrmgdon beds are Rowde, Seend, Calne, and Farringdon: the recorded species are to be found in the ‘ Mineral Conchology,’ in the lists of the ‘ Geology of Cony- beare and Phillips,’ in those of Dr. Fitton, prepared by Mr. Lons- dale and Mr. Sowerby, and in Mr. Morris’s Catalogue. In the Table of Species a column is added for the “ gault and upper greensand,” for the purpose of comparison with a portion of the true cretaceous series of this country. The numerous physical considerations we have gone over will however preclude the possibility of the Farrmgdon sands being grouped with the gault, even did the two accumulations present some amount of agreement in their faunas ; the gault, moreover, is not an independent formation, but merely the accumulation of a given condition of deep sea, synchronous as a whole with that portion of the cretaceous deposits which we call ‘upper greensand.” ae) I~ = 1850.| AUSTEN—SANDS AND GRAVELS OF FARRINGDON. “WOT “PTAA pue quay jo puesuoaid Spy |e coe te iets seisaiec un "sreeeleos TOTINOG ‘UOpUIMG sando0s00006 yynourta Ay "ee8e° BABTTOARTO "YqVOTT TTOMSYIOT | ree LOO ITTS 7) pee Dace acuaboceEs| a6 Stare (a(ia VIUOSILY, snyeuoquin snyjout.sa A ‘uOYYy "THH syourmg)"***s*s*""* qynourdoa|'*’ essoidop vroe.yy, NP 9419, T]"** WOT] UMOPYOVT] etree ee see eset stew ee neenes reece eseelen eens AmqstJ, TOP) tt teeeeeeees eel papapoxa Byjaqtun y, | yong’ ‘o1y1[00 DOOROOOOOOOOOOS OOOO OCOOOONCnO SSCS ODOgNeN OOSSOnCONOg Coo nno Con OCnsOnnt Shnhnnntnrnnnnn uopSumiey Goer ip deers ioc aig es (ese Nese cco inaeem eee eevee “a> a DOTTY "009N. ‘SILT See e wwe ree era erlerreeee es eer rT easeaeaeeees [rer DeHeEHeOOEs eH tagneoeess *T[9MSIOOT ‘uOpsULLe | TOP oe reese necener sees oesl sos ooaressnreerenereseverss stressors BATOTGO eee dVIYILY Pp *aPMOY “20ON ‘SITE COUITPOO| teers etree teeessteeees eee sleoeeee "009 ‘USpTea A, ‘TTAMSOO'T ‘uopSutsiey BTS LS EMBERS SCG DOGO SEEO-OREEEUCSOOSnME oor | cidyeLoy healt ‘T2MSYOOT ‘uopSuLme,y sb siak SUR oar Soto Rose reco: eo aauso OAUr Hon caring Bnyearqara I, UMOPHOV[T ‘QUOISHOT| sss [ewe eee eee w eee eeeee eeeeee eerleesceescesesercees z0) ‘W Cw Or rece eerser sens egegresees wNaploudd wunIejos : “UOPTT “GUD reser treet testes eee ec dete ee cee ease eres UOT] eee eseeeiee orgereA elndlag "TOMSYOOT] 8s" 88""** T9AOJOYS|"** [SVA [eLog] uoyepy] uMpisit euM0yso18e]J “mssnd “pyeo A\ CPeethHSCEP©® TOMEMOOT| Cee seen sneeeeteasecsiecdanetincesesascescdeses ee egine ““-sisuarut0000u —— *000N “wmissod “pyeanyl tt ]]OASyOO'T CPP e reer e Ere Hoes eeeseecssleereesr rs easersseregetoteselegy SNYLII}S19}UT T ‘WOU, -SItH Poorer vores erslecevcssceveeeses SOZIAN(T,W04ITY JO pursusass cf PSR SS OSCR COPS G8) GGSAO cveleeserseee 18z “d ‘U0441] Coo cers sees escssesseverestons STAVTMOTGIO 19409q TY SMOULRSTLETP [teeter eens ee eec teed eeese te eeesceteeeseeeen ers [sta10 JN os-3n] SPANO Vy gue wns aa ces cgbestrous:| dete se= "ce aemsscreamerm leno dl Bard Onud ‘00N | — fupyxperg ‘stay aurdry|48t44 Jo OST “PCO ccs ttteeet ees fo coyT pue 9 “yale [Aepo projzxg] SOPIO[NOIAR VIPAT) “q1Q,P*909N Soe T HCOOH ea ere reseeeerereerioreeaeareeerresrstteseceseseleseesceegese opMOYW ‘oure) COP weer Fares ereesesesoarss|FF FOSS ESF eon e reer egussossvsloco Toe psuo'T SVIIOICL UMOP YLT ‘9U0}SH[O,q 10441 JO puesudaas Fig fl SAB COCO AGRE oR a Gos dREOOC 08 Sot BOCOOSOTL O&z “d a (oN iig | Ge Sep eaIe oo: veces etlessees PAIRA ealoyyAy “SUOT] 29 "MOG PITOMAS TOON] |iuaeoueesiae cme tues sme niser |e [onto] ra8Soqg|'''""* umypnyerys “deg ut ‘yooqing U07}1q JO puvsuse19 TT POCO emer recede one eersersereens ‘ puepy.o0g ‘UOpUIMS wet e cece tenses ccccegesscccsleee d[LWISSTp TUnIpIVey) STAKOD SOC] Gilosm snes uae sean sm aie eee POCO BPS PENCE SEROS DOCS RTO Cite Ly'9) CASTING STup ls ee Steines eerie eeccee “2°"* MIvOUNI O}1VISV "200N ‘STI once cee enceeelececees ene reregeerstassesslaggccrcssoeei vensscsteveces SEBS NOH aR IGN Gab I. 9). y ayy | cM ScICSE cy SU DMLE = @) eee seme eeelas SISUOTP[ABINN “OpMOY Ce On SO nn i i ee rr snyejuap sopIUOWMUY foment see | ne Oa "dNVSNUTUDH "SITAVUD “ANVNUG “TONVU *NVINOOOD ‘aN g i) q | agaa A GNV wtavy N aNV SQNVSNOU] oar Sod ag ee 474 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 19, In this list it is very probable, or even certain, that there exist many incorrect identifications, but we may also assume that as they were not arrived at with reference to any such views as those of the present communication, such errors would only partially affect the value of the list as a whole, with reference to the general considera- tions it seems to suggest. What cannot fail to strike every geologist is, that so many com- petent observers should have recorded so many species as common to the upper portion of the oolites, and the lower of the cretaceous series. Prof. Edward Forbes informs me that Sir Philip Egerton identi- fied the remains of the fishes he collected at Farringdon to be, with one exception, oolitic forms. In addition to the Farringdon beds, we have also in this country another group of strata, at Speeton, resting on the Kimmeridge clay, not continuous or co-extensive with the gault, and which also seems to present a lke admixture of oolitic and cretaceous forms; and we shall also see that a like association is presented in the marine formation of Hils, and in the upper oolite of Boulogne. Guided by the considerations set forth in the local description of the several deposits, but more particularly by the unconformity which exists between the Farringdon beds and the great mass of the cretaceous series; as well as, secondarily, by that intermediate character in the general aspect of its fauna, I would venture to sug- gest that we should abandon the present abrupt limits we have hitherto assigned to the oolitic and cretaceous series respectively, and that we should see in the beds m question traces of the deposits, and a record of the conditions, which may partially serve to connect them. In proposing such an arrangement, it fortunately will not be necessary to introduce any new name or system into the already overburdened nomenclature of geological classification; the condi- tions which the Farringdon deposits seem to establish come as proof and confirmation of the value of a division already introduced by continental geologists, on considerations of the distribution and range of fossil forms, and to which they have given the name of “ Neoco- mian,”’ but which has hardly been accepted in this country, partly from deference to the term ‘lower greensand,’ and partly from a restricted view, that the scale of British deposits is to serve as the type and measure of the geological changes of all time and all places. I shall therefore show as briefly as possible, that such a view is not only inconsistent with what we know of the subcretaceous group gene- rally in its range across the European continent, but that the Far- ringdon deposits explain the nature and extent of the physical change which separates this group from the true consecutive cretaceous series, on the one hand, and how, on the other, it presents here the like order of connection with the oolitic series below, which it does elsewhere. Physical changes, whether of elevation or depression of an oceanic area, produce different geological effects, according to the conditions of the several portions of such area in respect of depth: the depres- sion of a portion of the deep sea deposits of a given period, so that 1850.] AUSTEN—SANDS AND GRAVELS OF FARRINGDON. 475 after such disturbance such area should still continue to belong to the deep-sea zone, would not necessarily be productive of any very distinct geological features, such as that of want of conformity ; and the only evidence of such change might be in mineral character, or even in the colour of the deposit, as in the case between the upper marls of the new red sandstone series and the lower marls of the lias. In this instance the whole series, from one to the other, is presented in our own southern counties as a consecutive one, and it is only in places where the physical disturbance produced a very different set of conditions over given areas, that the long lapse of time and the succession of changes in animal life are recorded, which really sepa- rate the new red sandstone group from the liassic. The change which separates our lower greensand from the gault, over the Wealden district, is viewed as merely a change of mineral character; but the transition is everywhere so abrupt*, as to signify that a vast amount of physico-geographical change marks the separation; and it is this feature of change which corresponds with the broader line of separation indicated at Farringdon between the gault and the beds next below it, and shows that the continuity of the two deposits is only apparent, or, in other words, that with reference to their physical conditions, they are independent groups. Nor is this independence less strongly marked with respect to the fossil fauna of the neocomian, as compared with that of the gault and upper greensand deposits}. This fact was clearly established as to the portion of the neocomian which occurs in the Isle of Wight, by the joint work of levels, and determination of species, of Prof. Edward Forbes and Mr. Ibbetson, and is asserted most broadly with refer- ence to the neocomian of France by M. d’Orbigny ; but whilst the upper part of the neocomian is thus dissevered from the gault, the line of separation does not seem to be equally broadly drawn between its lower beds and the oolites. In Switzerland, as at Villengin, and along the course of the Leyne, whence the type of the “lower neo- comian’’ was first taken, there appears to be a perfect continuity from the group of strata representing the Portland and Kimmeridge beds into those containing Spatangus retusus, Lamk. We have already seen the extent to which very competent observers in this country have traced out an agreement between the oolitic and neocomian forms. Prof. Phillips speaks decisively as to the mixture of Kim- meridge and cretaceous species in the beds of Speeton and Knapton ; and at the Meeting of the French Geologists at Boulogne, certain reputed cretaceous forms are stated to have been found in the Port- land beds, such as Corbis corrugatat, Sow. sp. * In point of fact, the gault here has been deposited on an uneven surface of lower greensand. + Of the molluscous fauna of the so-called lower greensand of the S.E. of England, not a single species passes up into the gault. £ Nor is this the only locality where the reputed lower beds of the cretaceous series would seem to belong rather to the oolitic. After describing a section at Saulxce-aux-Bois, M. d’Archiac observes, ‘‘ On voit qu’ici il y a eu une sorte d’os- cillation entre les derniers sédimens jurassiques, et les premiéres couches créta- cées.”—Groupe Moyen de la Form. Crét. p. 283. VOL. VI.—PART I. 2. 476 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 19, In the following list I have recorded only such species as I col- lected and have had time to examine ; and with respect to some forms of Terebratule, I have omitted them for the present, in consequence of the difficulty which their variation in form presents. List of Farringdon Species. ScYPHIA. subfurcata, Roem. Ool. t. 17. f. 24........000- Hils, conglom. infundibuliformis, Goldf. t. 5. f. 2 ........006. Hils, conglom. MANON. peziza, Goldf. t1.f 8)4.'29. £58 ee cece Oolitic and Neocomian. TRAGOS. hippocastanum, Goldf. CRICOPORA. gracilis, Goldf. t. 10. f. 11. PUSTULOPORA. madreporacea, Goldf. t. 10. f. 12. VERTICILLIPORA. anastomosans, Mant. sp. CipARIS. variolaris, Goldf. SALENIA. areolata, Agass. ARCA. Schusteri, Roem. p. 70. t. 9. £. 3. secssseceeee Devizes, conglom. ? Compare with A. biloba, Roem., oolitic. Furze Hills, in ironstone. CARDIUM. subhillanum, Zeym. Casts in ironstone, Furze Hills; 333.03cia ho See eee Neocomian. Nvcuta. scapha, d’Orb. Casts in ironstone, Furze ills. Opts. neocomiensis, Leym. & D’ Orb. Cast in iron- stone, Wurze Fills: “fio aus ncrasicancaseecen Neoc. of France. Mr. Cunnington’s collection may possibly contain another sp. VENUS. parva, Sow. Furze Hills, in ironstone ...... Neoc. of Weald, Isle of Wight. fenestrata, Forbes, Journ. Geol. Soc. vol. i. p- 239. pl. 2.f.6. Furze Hills, in ironstone. Neoc. of Weald. EXoGYRA. OsTRZA. carinata, Sow. macroptera, Sow. Fectangularis, Rocm. ....scicesssoce-socsenes Neoc. of N. Germany. PECTEN. Robinaldmus?, DV OVD. . .weccvercsgascawnavines Neoc. of France. ° atavus, Roem. ’Ool. t. 18. f. 21. Ironstone, UZ OC ANIES (Sensis tents vstieciacewsep oan sme Hils, conglom., Neoc. of France. 1850.| AUSTEN—SANDS AND GRAVELS OF FARRINGDON. 477 TEREBRATULA*. sella, Sow. [ Forbes, Quart. Journ. Geol. Soc. vol. i. p. 345.] lata [latissima], Sow. PIU CTEOLINS, SOW oe «cists ole daisoecte aeice nels sierei-nn 0s Oolitic. D’Archiac. BON Ga SOW seewancnoesecsesce sees eceseerens Oolitic. Von Buch. truncata, Sow. (not T. Asteriana, d’ Orb.) ... Oolitic (uppermost beds),Germany. depressa, Sow. [Von Buch. subtrilobata, Leym. Mém. Geol. Fr. pl. 15. f. 7-9. tamarindus, Sow. D’Orb. T. Cret. pl. 505. f. 5-10. Moutoniana, d’ Ord. [Sharpe, MSS.] lentoidea, Leym. EMARGINULA. neocomiensis, d’Orb. Devizes. Furze Hills. Neoc. of France. Vassy. BELEMNITES. SUM UACT ALIS, LOCHs | 25 cca: -csenieewcenses oven Hils. NAUTILUS. Compare with N. depressus, d’Ord. ... Oolitic. In the question which seems to be raised by the position and con- tents of the Farrmgdon deposits, as here described, it is not so much the identity of specific forms which we have to consider as the facies of its fauna as a whole: between deposits which have no species in common, as between the neocomian and the gault and upper green- sand group, such a feature is the only one we can take as a means of comparison. An agreement of this sort, when it may exist, may perhaps appear to some as of no great value; if so, this is not the place to controvert such a notion: what is meant by the expression is this, that a genus or genera may be subdivided into natural groups : and that fossil forms often correspond with geological divisions, just as we find like groups among actual forms referable to particular re- gions of depth or of geographical area; it is this grouping which imparts to a fossil fauna its peculiar facies, as compared with another, when the same generic forms alone are considered. The facies of the liassic Ammonztes consists in the preponderance of Von Buch’s groups of “ Arietes”’ and “ Faleiferi;’’ that of the cretaceous Nautzli in the lines of furrows which cross them transversely. The neocomian ammonite (4. Nutfieldiensis, Sow.) is more nearly allied to certain upper oolitic forms than to any from the gault and upper greensand ; so much so, that it is constantly quoted as occurring in the Portland beds; and Mr. Morris, in his description of the Nautilus Saxbyi, pointed out that it was referable to a group of which all the forms were oolitic. In the same manner the neocomian species of Opis, according to M. d’Orbigny, is very like certain oolitic ones; a like result is obtained with reference to the Farringdon Belemnites, Tere- bratule, corals, and sponges. * The most abundant Terebratula at Farringdon is one which presents great variety of form, and which is evidently the same species quoted so often by con- tinental geologists as diplicata; it as often resembles dimidiata and perovalis of Sowerby, and several neocomian forms of Leymerie and D’Orbigny, and is most probably a form common to a great part of the oolitic and cretaceous series. NS Uv 478 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 19. The results which I infer from our observations, though the area visited was very limited, are not without some interest and novelty : they are— Ist. That the freshwater conditions of a portion of our Wealden were to some extent contemporaneous with the Portland beds, or belong to the oolitic period. } 2nd. That the ironsands and gravels of the counties of Wilts and Berkshire are of the age of the Neocomian formation of the conti- nental geologists. 3rd. That the Neocomian formation is unconformable with, and separated from, the true cretaceous series by a wide interval of denu- dation. 4th. That the aspect of its fauna is partly oolitic. 5th. That the identity of the materials of the gravel beds of the Farringdon and Portland beds shows the condition of the area of water, as to extent, depth, and direction of distribution, to have been the same for both. | 6th. That the Farringdon beds and their equivalents (lower green- sand) must therefore be considered as the remains of an independent formation, of which the greater portion was removed by denudation before the deposition of the Gault. 479 DONATIONS TO THE LIBRARY OF THE GEOLOGICAL SOCIETY, April \st to June 30th, 1850. I. TRANSACTIONS AND JOURNALS. Presented by the respective Societies and Editors. AcaDEMIE Royale des Sciences de Paris, Comptes Rendus de I’. Tome xxx. nos. 7-21. Prem. Sem. Deux. Série. American Journal of Science. Second Series, vol. ix. nos. 26 & 27. Philosophical Society, Proceedings. Vol. v. no. 44. Asiatic Society (Royal), Journal. Vol. xu. part 2. Astronomical Society (Royal), Memoirs. Vol. xvii.; and Monthly Notices, vol. ix. Athenzeum Journal, April to June. British Association, Report of the Nineteenth Meeting of the. Calcutta Public Library. Report from February to December 1849. Chemical Society, Quarterly Journal. No. 9. 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Puy, Société d’Agriculture, Sciences, Arts et Commerce du. Annales, vols. 1.—xil., and vol. xiv. Prem. Sem. Society of Arts, Statement of Proceedings preliminary to the Exhi- bition of Industry of all Nations, 1851. Torino, Reale Accademia delle Scienze di. Memorie, Seria Seconda, tomo x. II. GEOLOGICAL AND MISCELLANEOUS BOOKS. Names in italics presented by Authors. Admiralty. Sheets completing Vol. i. of Astronomical Observations made at the Royal Observatory, Cape of Good Hope, in the year 1834. Agassiz, Prof. L. Lake Superior: its Physical Character, Vegeta- tion, and Animals, compared with those of other and similar regions. The Geographical Distribution of Animals. Béron, P. Systéme de Géologie et Origine des Cométes, ou trés- court résumé du Deuxiéme Volume de l Atmosphérologie. Blackwell, J. K. Report on Ventilation of Mines. From Sir P. G. Egerton, Bart., M.P., F.G.S. Bouchard-Chantereauxz, M. 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MISCELLANEOUS. io iE a) aang ae tat ok os cu o's CO me & ret ii THAD 4O ay ai LATUQO © sieh Ipteqns ae 2r0dtwb sdf Yo tomy 313—heganren lise Pe » A See ee “ = ae ee a over 3 7 app HS ey ..... zao} go aga _»d3 no amvaMi aov H MW .nofttsoriol-[soD odi tos ade ecae moi elizeol a0 VAI ot beaisinos ite adi co wuameuaAH LM Rea -.@honsisdzd boA sinodis0 sO™ Js eee rotswdeonl adi of esdene to agua ligzot aC ino aiheW ey ot StriedocG 40 59097290 aor nO se este ate rage ced seb cee tee eeenteere ee eeecsei «ee hel dri 2 . .eSAd OF antnense asilgororalé io eee a Wis moitenrrot-died) orld to eitenl of? re smeaearcs Tee7 eo ge lo ateodqromobyseq .req2-I1RO) wey no woHoed .M .exonbledzG sat to atin edt oo HOUd gov corsd oto ad? wo watsalé ,M .cottenrol-sil Nae to norteariot oft no Taa® a3 to atoll fizeot sit co TaaTqOW to1d . of cso Taaaa00 Jord £12918 9 git co rsaatd Mi QiobersM teen idogsal ody to anotisnrot-ais¥ od? cO~ ? ai i ; pice. 1 (eomgosd of abisO ettt To 9 to moftacntat od? sro AMM AHHOROT ord pee i , $3 to esrortsariot- ic) ¥ of? ac To) a2 ‘go sxoavaaall bas Ae eT me aria? £ atinoloG io corset ons nO ‘tod gs bocves BET 80 saormarad M 3 7 "Hoheis is90 cousarol-isod oft 29 5 5. sgsll@ to aottennol-[e0D siz nO Tae eutiasl tizect to Ree 3 ect co bas f ale af t lizaatt _noiam td a0.) 4 j Po Sele to teni-alsa ane 1 iit phewbhal i gio sivedié oxoit booW [iazct no IoOde sas ' oat ‘to sol rim ae 29 yo stol Phe 7 =a ya ear © sia a als CONTENTS OF PART IL. Alphabetically arranged—the names of the Authors in capital letters. Page BEE Seat): MELEE, ONL: LOSSIM 2 etree wtnrei nn cise tiste Aiwaiatele cbse tives clave cutetuime nouns 61 Archegosaurus of the Coal-formation, M. H. von MEYER on the... 58 Paver VERTAN On. Fossils: fro ine. < sss «sstels nessa senieea cia sins olathe os 58 Basaltic rocks, M. HAUSMANN on the Water contained in ............ 34 Biscuorr, M. On Carbonic Acid Exhalations..............csesececseees 40 Buium, M. On fossil Eggs of Snakes in the freshwater limestone at UTP ae LF cleric a siare cig ue Soe So mid oialonr ole deslaisie ainiere nig atasio whe Wen ve mee aca 42 Bresuavu, M. On the occurrence of Ozokerite in the Wettin Coal BERS PEO GAP ces. Sacha. ssisihic accic Sie caalcuaraierciere Alesse alas ama Ramee eS ECA 59 Brown-coal of Bribir, M. HornEs on Mammalian Remains inthe... 41 Bucu, Baron von. On the limits of the Chalk-formation ............ ae, Calamine and Calc-spar, pseudomorphosis Of ..........scseseceseeeeeeees 65 Carbonic Acid Exhalations, M. BISCHOFF On .........ccccceeeesecceces 40 Chalk-formation, Baron von Bucu on the limits of the ............... 22 Crinoidea.of the Jura-formation, M. MERIAN on the .................. 60 Coal Ero. GOPPERT-on the formation: Of sacviecse-0c0 deccscoscevcaccceces 33 Coal-formation, Prof. GOprERT on the fossil Flora of the ............ 13 Coal-formation of Silesia, Prof. GOPPERT on the ...........cecceeeeeeees 19 Coal-formation near Meisdorf, M. GrEBEL on the .........cesceccesees 76 rae M. B. On the Vein-formations of the Erzgebirge ............ Pat mNatice: of his Guide to-Geognosy!: s.cc. iitesscceconsevetedenee! 26 Dolomite, Prof. ForncHHAMMER on the formation of ...............00. 48 Erzgebirge, M. B. Corra on the Vein-formations of the............... 27 Fish, fossil, from Siberia, MM. MULLER and MippENDoRE on...... 45 ForRcHHAMMER, Prof. On the formation of Dolomite ............... 48 Geosaurus maximus, M. PLIENIGER On the ........ccccceccccvssvececees 58 GIEBEL, M. On the Coal-formation near Meisdorf .................. 76 GoprerRT, Prof. On the Coal-formation of Silesia ...............0eeee. 19 On the formation of Coal, and on the origin of fossil Resins. 33 ——. On the fossil Flora of the Coal-formation..................eece0. 13 ——. On the fossil Flora of the Grauwacke of Silesia ............... 35 ——. On Vegetable Remains in the Salt-rock of Wieliczka ......... 32 and M. MippENporF on fossil Wood from Siberia ............. 66 Grauwacke of Silesia, the fossil Flora of the .................ceececeeeeecs 35 eumde to: Geoonosy, M. Bb. COTrAacs; MOticed, ..cocescccsescscnnsseeessone 26 1V HausmMann, M. On the Water contained in Basaltic rocks ......... Her, ‘Prof..0.. ,On fossil Ants 205 2.0 3.0 teseew acs ceea- eee eee On ‘the History of Insects» ...1./2:i2.& cece ceteecenee] othe seen Hornes, M. On Mammalian Remains from the Brown-coal of BBP U UT Scio bia aids oidiore.clereid cisiawid ea atrowin ee ole alerebare oars toe et ee ee Insects, Prof. O. Herr on the History of.:....-0.22+.3..<<0s-2e eee Mammalian Remains from the Brown-coal of Bribir, M. HorNEs on GEE face cde ca cscnnicmeneeaecehoomtatel de caeces ewer Ga tcene on tan ae eee Merian, M. On Fossils from Arzo 1.22.22... Siccecckce.ss0ee.2 ee On the Crinoidea of the Jura-formation ............ceeeeceeeees Meyer, M. Hermann v. On the Archegosaurus of the Coal-forma- ELON. va ein's din a'e.cse Nea Sineldiniowayeictaisieiom's ciseses b Geis Sac te eae bie Con ene a MippEenporrF, M., and Prof. Mtuuer. On fossil Fish, &c. from Siberia 235. crouse sevens baeae ccad use dtweceecces cotiee sates cnuic tee ean and Prof. GOpPERT. On fossil Wood from Siberia ............ MonueEim, M. On pseudomorphosis of Calamine and Calc-spar from the Severin’ Mine... <0... .deescse0scenssenecss « sceuecinn glee MUuuEr, Prof., and M. MippENporF. On fossil Fish, &c. from IDETIA” Sostocccswccace cecuccduethscccsdncreaeeges cunts ths dee eee Ozokerite in the Wettin Coal district, M. BresLAv on the occur- FETICE OF 00d in.punrsae pos bedcacidae manicweoemee ever Son “ee eae CRORE nee eee eae PLIENIGER, M. On the Geosaurus maximus .......1...0ceceresecceeee Pseudomorphosis of Calamine and Cale-spar, M. MonneErm on the... Resins, fossil, Prof. GOPPERT on the origin Of ............seceeeeeeneeees Salt-rock of Wieliczka, Vegetable Remains in the..........-.eseceeeeeees Siberia, fossil Wood frotitwess.accssececdes. doesn ss beeesbeeoukee deco eaeaaee , Fossil Bish from ..:-0.00ccechae shock acs begatacan pols. beaeeeeeeeee Silesia, Prof. GOprpEeRT on the Coal-formation Of .........ssceceessccees Prof. GopPERT on the fossil Flora of the Grauwacke of...... Snakes, fossil Eggs of, in the freshwater limestone at Beiber, M. Brunt OM) gicelscemacnn. okshb cus -aakes eeesees serach dees tee eee Spain, Tertiary, Formations Of ..0::sc1s0.-cnes obs i poses the further percolation of water. ; At aspot in the Toftekuie, between the limestone and the Faxoe~ limestone, a perfectly distinct bed, composed of a yellow calcareous F sand [| Kalksand], intrudes itself, and in this stratum globular masses of dolomite occur. These bodies frequently attain more than a pound weight, and are often united into irregular masses similar to those i with which we are acquainted from other dolomite formations, espe- cially from Sunderland in the north of England. The dolomite con- tains no fossils, whilst the Faxoe limestone [Faxéekalk], the yellow i caleareous sand [Kalksand], and the limestone | Liimstenen], are - surcharged with remains of marine animals. I may add, that the - flint of the limestone sometimes penetrates the globular dolomite masses ; and that there is not found in the whole of Faxoe Hill the least trace of a chemical plutonic action, except its being the seat of springs. The effects of springs that have degraded the calcareous rock are everywhere visible. Wherever the coral-limestone is com- posed cf a mingied mass of sharp-sided fragments, these are super- Hi ficially covered with a coating of lime, yellow and ferrugmous; and — at many places the fossils become indistinguishable from a layer of | calcareous sinter. The thick limestone strata are perforated by nu- | merous large, perpendicular, tubular holes, having a diameter of 1-2 i feet. The workmen call them chimneys; they resemble the hollow wor pipes that are frequently found in the Danish and English chalk, the origin of which is now usually and with great probability referred to the action of excavating springs. These springs have formed the dolomite, not by directly depesiting » carbonate of magnesia brought up from below in a soluble state, but. by the carbonate of lime, held by them in suspension, decomposing the magnesia-salt of the sea-water, And indeed the globular form al---: ways assumed by the Faxoe dclomite is a proof of its formation by © means of springs. One cannot indeed well conceive that these glo-'0 FORCHHAMMER ON THE FORMATION OF DOLOMITE. ae bular masses were formed in any other manner than that in which the Karlsbad pea-stone, confetti di Tivoli, and all similar formations comprised under the term Roe-stone [Rognstenen], originated. This is brought about by water in one or two ways; it separates and brings up small particles, around which lime, disengaged by the escape of the carbonic acid, is deposited. As long as these separate particles remain washed about in the water, they must naturally be round, as the isolation is perfect on all sides; but when they ultimately become so heavy that the water cannot keep them im a state of mo- tion and therefore floating, they smk downwards and become united by means of the disengaged lime into connected masses. The for- mation at Karlsbad takes place m the same manner; and the only variation in the form of the two deposits is, that the Karlsbad piso- lite has a conchoidal fracture, which is never found in the dolomite spheroids of Faxoe, nor in that from Fullwell near Sunderland. But there is the great difference at Karlsbad and the other places men- tioned, that at the former the spring has a subaérial outlet, whilst the others had submarme outlets; and it is natural that in the first case far more numerous interruptions must occur, as expressed by the conchoidal fracture, than in the last, where the great body of water must make the separations far more regular. It results from the foregoing, that the size of the spheroids is a measure of the force of the springs ; and, for comparison, I will here remark, that the fountain at Tostrup Valdbye, giving 13,000 tons of water per diem from a bore of 6 inches diameter, could keep suspended a fragment of limestone weighing a pound. The spring- pipes at Faxoe have on an average a diameter of at least double this, and their current of water must have been at least four times as strong to have supported the floating dolomite masses of a pound weight. I may also add, that the globular bodies, formed by sub- marine springs, are easily distinguished from those arising from trituration (Roe-stone) ; the former are of unequal size on account of the very unequal motion im and near the spring-head ; whilst the trituration effected by the waves is uniform. Its form and mode of arrangement distinguish the Faxoe dolomite as having been the result of a submarine spring; and as the underlying Faxoe limestone is a marine formation, and the calcareous sand, in which the dolomite occurs, contains marine corals, and the limestone that surmounts the whole is likewise marine, it is impossible to entertain a thought of these springs having been extra-marine. It could scarcely be supposed that the springs would have had their issue at the top of the hill, and not, as now, at the foot; but on a closer examination of the various conditions, it will be evident that the sprigs must have burst from the top of the hill, as appears from the spring-pipes that they occupied. We imagine that fresh water penetrated the Faxoe Hill when the sea still covered the whole formation ; and, therefore, that the place, where the springs would issue, would be determined by the greater or less resistance opposed to them. At present the least resistance is where the springs break out at the base of the hill, the counter-pressure there being the at= - MESSE "SAS pets ee = — a = = - men Se ~ see Seti es > a a = Se ae Ts. Se SS SS So SS } 54 GEOLOGICAL MEMOIRS. mosphere; the whole of the crevices within the hill bemg occupied by fresh water that resists the upward direction of the currents. If the whole were covered with sea-water, its depth beg but slight at the top of the hill, and supposing that the pressure of fresh water within the hill had force enough to keep out the sea-water from all the cracks and clefts of the rock, then, as the height of a column of fresh water within the hill, and that of the sea-water at its base, would be equal in bulk, the difference of the specific gravity of the two fluids would cause the fresh water to ascend in the hill and to burst forth at the top in springs. We will now speak of the chemical relations. It is very evident that the iron contained in the Faxoe dolomite has been derived from the water of the springs, because all the sinters of that date, hke those which are found in the separated concentric layers, the thickest of them being in a semi-stalactitic state, are ferrugmous. That, on the other hand, the magnesia of the Faxoe dolomite was not brought hither by the springs, is apparently proved by the fact that the sinter- - like masses deposited in the mterior of the Faxoe limestone do not contain an essential quantity of magnesia. The composition of the Faxoe dolomite is— I. it, Carbonate of lime .......... 80°67 79°89 Carbonate of magnesia ...... 16°48 17°03 Dilip an ei eka nt sate a cece 0°81 0°65 Fron. (Agel Pn. eae n » VINO 1:29 Water and loss. 2... 4.5. 61292 1:14 100-00 100-00 In the first analysis the lime was not weighed, and the water and loss were not calculated. The yellow sand-like limestone which contams the dolomite is composed of— Carbonate of lime and loss ...... 95°75 Carbonate of magnesia..........- 0°64 ‘Perrdsiious gibtea’ 211. 2 SPSL 2°74 rem P60 We Ah Oe ree 0°87 100-00 I have at the same time made analyses of the Faxoe limestone and of the upper limestone, both of which contain a very small proportion of magnesia. We learn then from chemical analysis that all the limestone at Faxoe has been deposited by sea-water by the intervention of animals, and that the dolomite contained in it, and either contemporary with it or of an anterior or posterior date, contains just such a proportion of magnesia as corresponds to that which the marine, lime-secreting animals always contain. The sinter deposited in the crevices of the coral-rock, and derived from the fresh spring-water, contains also only FORCHHAMMER ON THE FORMATION OF DOLOMITE. 55 a small quantity of magnesia. There is deposited, on the other hand, a mixture of carbonate of lime and carbonate of magnesia where the spring-water has come into contact with the sea-water. We can scarcely doubt that the carbonate of magnesia is precipitated by the action of the water of these springs upon the magnesia-salts of the sea-water. To confirm this theory, I have examined into the manner in which mineral springs act upon sea-water. This examination is not finished, and several points remain that are not yet satisfactorily elucidated ; but the results already arrived at are quite sufficient to show that the dolomitic limestones and dolomites are formed by this mutual action of the springs and the sea-water. My first series of experiments relate to the mutual reaction of sea- water and a solution of pure carbonate of lime in water charged with carbonic acid, under different temperatures. The carbonate of hme solution I call, for the sake of brevity, ‘‘ carbonated lime-water.”’ 1. Carbonated lime-water mixed with sea-water was set in a frigo- rific mixture until it was all frozen. After thawing, the deposit con- sisted of— Carbonate.or limer ee .ks ueoe ep Carbonate of magnesia .... fen 100-00 2. Sea-water mixed with carbonated lime-water stood for eight days in a temperature of between 15° and 20° C. (determined by a ther- mometrograph) ; the deposit was composed of — Carbonate of lime ........ 97-81 Carbonate of magnesia .... 2°19 3. The same mixture at 50° C.— Carbonate of lime ........ 96°22 Carbonate of magnesia .... 78 ne 4. The same mixture at 87° C., in the vapour bath— Carbonate of lime........ 87°36 Carbonate of magnesia .... on 100/00 5. Sea-water was brought to ebullition, and carbonated lime-water poured into it in a fine stream, so as not to be lost by the boiling :— Carbonate of lime ........ 87°75 Carbonate of magnesia .... | 100-00 6. A similar experiment— Carbonate of lime........ 89°64 Carbonate of magnesia .... 10°36 \ 100°00 The above experiments are those of a series, in which the greatest quantity of magnesia was precipitated under the given temperatures ; but I obtained many less proportions, and these seem partially to be dependent upon the variation of mutual action; insomuch that the longer the inter-action is continued, the less magnesia is proportion- ally present in the precipitate. In like manner I obtained by evapo- 56 GEOLOGICAL MEMOIRS. rating nearly to dryness a mixture of carbonated lime-water and sea= water at a temperature of 90° Centig. and washing the precipitate, a proportion of ea 4 Carbonate of lime...... 98°51 100-00 Carbonate of magnesia.. 1:49 eee This explains why the roe-stones contain nearly pure carbonate of lime, for the chemical action must in their formation have been ex- tended over a long time; and hence it follows that this carbonated: lime-water at the boiling-point of water can only deposit a quantity of magnesia below 13 per cent. of the whole compound ’ precipitate’: this is my reason for fixing the limit of the ‘‘ dolomitice limestone?” The next series of experiments relate to the action of the carbo- nated aqueous solution of lime and soda [natron]| on sea-water: ; This solution was prepared by adding as much carbonate of soda to the usual carbonated lime-water as it could bear without becoming clouded.) :~ In three experiments I obtained, under different degrees of heat be= tween 50° and 100° C., 13:10, 14:85, 27°93 per cent. of carbonate of magnesia. In these also there oceurred the same uncertainty of re= sults as in the experiments with the pure carbonated lime-water, evidently occasioned by certain conditions as yet unrecognized. This: much, however, results from these experiments, that the carbonated natron-lime-water deposits a greater proportion of the carbonate of magnesia than the pure carbonated lime-water ; and whilst the latter precipitates ‘‘dolomitic limestone”’ from sea-water, the former sepa- rates ‘ dolomite.” The third series of experiments will serve to determine how some of the best-known mineral sprmgs will act upon sea-water when brought into chemical relation with it. ‘The decompositions were made with the aid of boiling. . | Selters-dolomite was composed of— Pyrmont-dolomite, calculated after the double iron-salt proportion. was separated from the carbonated salts— Carbonate of lime...... 84°38 Carbonate of magnesia.. 5°12 7100-00 eo ee APRS Oa 10°50 Wildung-dolomitic limestone is composed of Carbonate of lime. .... 92°12 : Carbonate of magnesia. . ee tae I have never obtained in my experiments dolomites that were as rich in magnesia as they frequently occur in nature ; but I also freely acknowledge that my experiments are very imperfect imitations of nature ; and with regard to the temperature, it plainly results from the theory, that the springs that now issue out with a heat of 100° Centig. would have a higher temperature if the pressure of the air were stronger, or if they came out under considerable pressure of water, FORCHHAMMER ON THE FORMATION OF DOLOMITE. DF and the experiments establish that the proportion of magnesia in- creases with the temperature. I cannot leave this part of my subject without remarking, that these observations on the Faxoe Hill explain a phenomenon to which I have previously drawn attention, yet without then being in a position to explain it. The stratum, of which Faxoe Hill is a development, is found over a very large portion of the Danish chalk, but m general only with a thickness of two or three feet. At Faxoe it increases to a thickness probably approaching a hundred feet, and it assumes in its physical relations the character of a coral reef. The cause of this local development is proved by the discoveries above given to be owing to the calciferous springs bringing up such an abundant supply of lime for the marme animals; the warmth of the springs, moreover, favouring perhaps the development of the latter. In many respects, the well-known dolomite from Fullwell near Sunderland is analogous to the Faxoe dolomite. The same sphe- roidal masses are found at both places; but at Fullwell I have seen them with a diameter of 4 feet. On the other hand the Fullwell dolo- mite is distinguished by a form that is not found at Faxoe, viz. the so-called ‘‘ honeycomb-stone,” a delomite that is full of holes that are somewhat regularly arranged like the cells of a honeycomb. These have been evidently produced by bubbles of disengaged car- bonic acid gas, and are very important as they here occur in connec- tion with spheroids formed by the action of springs, and therefore explain the origin of the cavities, whilst on the other hand they form the connecting link with the very cavernous dolomite that especially occurs in the geological period now commonly recognized as the Permian epoch, and to which the Ruevakke belongs. From these observations we can now also comprehend why the formation of gypsum is collateral with that of dolomite. Gypsum having formerly been carbonate of lime from which the carbonic acid was driven out by sulphuric acid, as is now usually accepted by geo- logists, the carbonic acid so disengaged must, when water was present, have redissolved a quantity of carbonate of lime; and the reaction of this solution on the sea-water must have formed dolomitic lime- stones. dereto belongs, for example, the singular dolomite of Stipsdorf in Holstem, which is black and cavernous as a lava, and contains somewhat worn specimens of the fossils of the brown-coal formation, together with our common grayel-pebbles [ Rullestene]. Its composition is— Carbonate of lime.......... 80°55 Sulphate of lime .smgmenayt 0°95 Carbonate of magnesia...... 7°49 ro) IBLE Naan saa ets aie SAE Seger 9°82 Tron ant areilla™ - 2s. eee 2°83 Coal, water, and loss 2... 3. «=. 2°36 (T. BR. J.) . ig es ere <* ereg es Se eS 3 w= ae sea eet - se ‘ — a 5 peerage SETS wa re Se ee Sa ee ae ae et a 2 SESE ‘eat aden, asec 58 GEOLOGICAL MEMOIRS. On the Organic Remains from Anzo near MENDRISIO. By P. MERIAN. [Basel. Verhandlung, 1846-8, vill. pp. 31-33, and Leonhard u. Bronn’s Jahrbuch f. Mineral. 1849, p. 866.] Cart Brunner and Rud. Merian have collected from the red and white marble-like limestone of Arzo the following fossils, as determmed by the author of the communication. Lima, small, and very similar to L. Hermanni, Voltz ; Pecten, internal cast, closely agreemg with P. textorius, Munst.; Terebratula, very near to T. ornithocephala, Sow., plentiful ; Teredratula, agreeing with T. tetraedra, Sow. and T. quinquecostata, Ziet.; and Spirifer rostratus, V. Buch, and Sp. tumidus, V. Buch, which moreover appear to pass into one another. All of these species distinctly point to the lower part of the has. In a grey marlstone at Tremona near Arzo occur Terebratule, of perhaps the above species; Belemnites, Pecten, Pentacrinus, and a small undescribed Sponge. This must, therefore, necessarily be las. From Monte Generoso, Brunner obtained the following lias fossils : Terebratula ? tetraedra, Sow., Spirifer rostratus, V. Buch, Sp. tu- midus, V. Buch, and Sp. Walcotii, Sow. (T. R. J.] On the GEOSAURUS MAxIMUS. By Tu. PLIENINGER. [ Wirtemb. Jahresb. 1849, v. 252-253, and Leonhard u. Bronn’s Jahrbuch f. Mineral. 1850, p. 128.] A siock of the so-called Ulmer Portland-oolite contained a fragment of a lower jaw from near the symphysis, with seven large conical teeth. These were hollow for two-thirds of their height; open at the base; with a two-edged point; and bent inward and backward. The author had described them under the name of Geosaurus mazi- mus in the Jahresb. i. 150. As however the teeth are evidently fixed in alveoli, this animal belongs to the Thecodont Saurians, and perhaps ought to be united to Belodon. (T. R. J.] eee Se On the ARCHEGOSAURUS of the CoaAL FoRMATION. By H. v. Meyer. [Dunker u. Meyer’s Palaontograph. i. 209-215, pl. 33. fig. 13-17. Comp. Leon- hard u. Bronn’s Jahrbuch f. Miner. 1848, p. 468, and Jahrb. 1850, p. 104.] Tue author describes a new individual of Archegosaurus minor, con- sisting of a skull and part of the neck, n H. Schnur’s collection at Treves. He refers also to his discourse at the Meeting of Natural Philosophers at Aix-la-Chapelle, in 1847, where he first saw the spe- cimen. On both occasions he has combated Goldfuss’ opinion, that it was referable to a crocodile ; he has moreover proved its labyrin- thodontoid character, and induced Goldfuss to alter his first opmion on the subject. He proceeds to cite the notice of Goldfuss’ work im the BRESLAU ON THE OCCURRENCE OF OZOKERITE. 59 ‘Jena Literatur-Zeitung,’ 1848, 654; and in many respects adds much to a knowledge of the animal. He accepts Goldfuss’ view that the osseous apparatus, posterior to, and in connexion with the skull, belongs to the bone of the tongue ; and quotes also Goldfuss’ words, that the Archegosaurus, by the presence of scales, affords a proof, that there existed, in the case of the mailed reptiles of the ancient world, representatives of a regular larval state; just as in the case of the Batrachians we have the fish-reptiles of the present day. The Sclerocephalus Haeuseri, Goldfuss, lastly, appears to the au- thor to agree in the formation of its head, even more than the Ar- chegosaurus, with the Labyrinthodons, and must therefore also be numbered amongst the Saurians. [(T. R. J.] —— On the occurrence of OZOKERITE in the WetTtT1IN Coat DistRIctT. By Herr BRESLAU. [Karsten’s Archiv fir Mineralogie, Maison u. Ss. W., B, xxiii. H. ii, pp. 749-751*, 1850. THE occurrence of the Ozokerite in the Wettin coal district is con- fined to a cleft found in the Neutzer Zuge, in the year 1848, in the farthest shaft of the Burghofer pits, at 231 to 243 fathoms, and some neighbouring clefts, in the sandstone that is situate between the shelly schist, forming the uppermost beds of the coal formation, and the limestone that overlies the uppermost coal bed. The sand- stone alternates above with a clayey rock, and below with a calcareous claystone ; and is characterized by its greenish-grey colour, its fine grain, its clay partings, and by its general want of mica. As an exception, that portion of it, which is otherwise altogether free of intervening laminze, contains a trifling layer of reddish-brown clayey sandstone. The cleft begins at 3 of a fathom above the brownish-red sandstone layer, passes through it, and terminates at the uppermost bed of the calcareous claystone, at 14 fathom above the upper coal bed. Its strike is hor. 2, 2; and its dip is about 80° E.S.E. The sides of the cleft are covered with cale-spar, which is here and there crystallized in druses, and on the sides near the middle of the cleft is generally beset with small crystals of sulphur-pyrites,—hexa- hedral iron-pyrites, Mohs. The remainder of the cleft is occupied with the Ozokerite. The cleft is very unequal in size; sometimes it expands to half an inch, and is sometimes contracted to} inch. This circumstance, on account of the laminated texture and symmetrical arrangement of the contents of the cleft, acts im suchwise on the variable quantity of ma- terials present, that towards the middle of the cleft the Ozokerite is almost absent ; and, whilst the mass of Ozokerite attains a thickness of + inch where the cleft has its greatest width, the cleft at its nar- rowest portions is occupied with cale-spar only. The small neighbouring clefts, running parallel to the chief cleft, exhibit similar contents, having a similar symmetrical arrangement * Accompanied in the “Archiv” by an illustrative Section. 60 GEOLOGICAL MEMOIRS. from the sides towards the middle. Cale-spar is always the most plentiful constituent, and is never absent when Ozokerite occurs. The rocks of this district have a conformable stratification, the strike bemg hor. 4, 2; and the dip 12° S.S.E. Nowhere is an in- 4 trusion of the cleft visible in the schist formation, nor in the neigh- i bouring rocks. The sandstone in its neighbourhood is either of a pale colour or bleached, and contains only sulphur-pyrites in little nodules. The red colour of the sandstone layer, noticed above as an intermediate stratum of the greenish-grey sandstone, is quite distinct i from the cleft, and independent of the occurrence of the Ozokerite. | The coal of the “upper bed,” from the deepest part of this pit, which, with the exception of the somewhat variable uppermost bed, the so-called roof- or first-coal, is of very good quality, is nearly | throughout this part of the district subject to discharges of combus- e tible gas. We may perhaps presume that the origin of the Ozokerite hy is connected with this condition. The circumstance of no connexion being proved to exist between the Ozokerite gas and the coal beds in this pit, constitutes no objection to this connexion existing elsewhere. i The Ozokerite of Wettin, in its occurrence in the neighbourhood 4} of coal beds, resembles the Ozokerite of Slanik in Moldavia, that of Gresten near Gaming in Austria, and that of Newcastle-on-Tyne. It i has a yellowish-green colour, and is so soft that it may be kneaded between the fingers. (T. R. J.] es On the CRINOIDEA of the JurA Formation. By P. Merman. 4 [ Basel. Verhandl. 1846-1848, viii. 27-29, and Leonhard u. Bronn’s Jahrb. f. Mineral. 1849, p. 876.] THs notice is supplemental to a communication previously made on Uf the subject by Desor. Apiocrinus Meriant | Desor], Goldfuss, pl. 55 li (with the exception of fig. D, which is 4. Rotssyanus, D’Orb.), be- | longs to the so-called Sequanian formation,—the lowest portion of the Portland oolite, where it commences to be coralliferous, imme- diately above the corailine oolite. This species is often confounded with 4. rotundus, Miller, which occurs much deeper, in the Bradford clay. The former is distinguished from the latter ‘by two small accessory plates between the two middle pieces of the body ; further, the basal pieces form a great part of the cavity, nearly as great as that of the first middle pieces in 4. rotundus.’’ Millericrinus (Po- matocrinus) Hofert, from the same formation, is a species with a semiglobular body, and by its uppermost column-joints is allied to M. mespiliformis, Schlot. sp.; it has been already figured by Hofer, Act. Helvet. iv. no. 48. pl. 8. fig. 19-21, and only lately again dis- covered by Koechlin. Millericrinus polycyphus, Agass. [Desor?], was until lately known only by its stem-joints, which occur with the if heads and other parts of M. rosaceus, Des. [Schlot. sp. ?], m the lower beds of the coralline oolite, in the ¢errain a chailles. Chr. Buck- hardt has now however discovered near Fringeli, in the Canton Solo- thurn, the body portion of M. polycyphus, which turns out to be a species of Apiocrinus. [T. RB. J.] TRANSLATIONS AND NOTICES GEOLOGICAL MEMOIRS. On Fossiu Ants. By Prof. O. Herr. [Mittheilungen der Naturforschenden Gesellschaft in Zurich. Heft ii. pp. 167- 174, 1848.] Tue Ants are amongst the most numerous of the fossil insects both at Giningen* and Radoboj, and offer many points of interest to the geologist. We especially refer to the followmg :— _l. Nearly all the fossil Ants are winged, and either male or female ; two specimens only of the neuters have as yet occurred to me, although these latter without doubt constituted the majority in the ancient world. The reason of this is very clear. The winged Ants only could rise into the air, and so be driven into the water, where some of them would perish and be covered up in the mud. But these fossil Ants clearly show that this covering up by the mud must have been very sudden, and much more rapid than in our exist- ing lakes and ponds. The wings of Ants are but very feebly attached to the thorax ; they remain on only until pairing takes place, and then fall off of themselves; and indeed even before this they are very easily separated. Now were the Ants to lie even a short time in the water before they were imbedded, the wings would surely fall off. 2. Among the fossil Ants many more females than males occur both at Giningen and Radoboj. I have altogether examined 279 specimens of fossil Ants, of which 208 are female, 69 male, and 2 neuter. From Ciningen there are 118 females and 40 males, and from Radoboj 90 females and 29 males ; there being obviously at both localities about three times more females than males. Among existing Ants an inverse proportion obtains; for, accord- ing to the researches made by Huber, there occur on an average three times more males than females. Probably the same proportion also existed in the extinct fauna; but more females fell mto the water, being feeble and unwieldy, and so perished in greater proportion than the more active and lighter males. Hence also arises the suggestion * [See Description of the Freshwater deposits of @ningen, and Observations on their Fossil Fauna and Flora, by Sir R. I. Murchison, Trans. Geol. Soc. 2nd Ser. vol, iii. Part 2. pp. 277-290, and Quart. Journ. Geol. Soc. vol. v. pp. 233-237.— Ep. | VOL. YI.—-PART II. EF 62 GEOLOGICAL MEMOIRS. that the Ant-swarms did not suddenly perish from outbursts of steam or from any other such-like cause, for all the mdividuals of a swarm would in that case have fallen together into the water and have be- come fossilized. This probably was not the case, as the males have for the most part escaped. It is also rendered unlikely by the eir- cumstance that in Giningen large groups of Ants are never found together in one stone, but generally only a single specimen, or at the most two or three. At Radoboj a greater number of individuals often lie together; but for this, as we shall see, there is another ex- planation. 3. At Radoboj slabs of stone often occur on which a great number of organic remains are assembled together. There are found, for ex- ample, on one stone of a few square inches, one specimen of Formica pinguis, three of F. pinguicula, one of F. Hesione, one of F. Telamon, three of F’. ophthalmica, one of F’. oculata, one of F. Hecuba, one of F. Priamus, one of Bembidium, and various fragments of plants. On another stone we find Formica pumila, F. pumilio, F. pinguicula, F.. obscura, Amphiotis bella, Harpalus tabidus, a Gnat, and a Bu- prestis. We often find on the same stone leaves of trees, and still more abundantly various-sized fragments of Cystoseirites communis, Unger, a marine Alga, which is one of the most abundant plants at Radoboj. ‘This clearly proves the former presence of sea-water, into which the land-animals fell; and hence we can explain why the larvee of the Libellule are absent here, which play so important a part at CEningen. In the place of the larvee we have at Radoboj some full- grown Lidellule ; these animals, therefore, were existent at both places at the same time. There was evidently at Radoboj during the tertiary epoch an arm of the sea into which a river flowed, and in which river the larvee of the Inbellule had lived, together with water-beetles, a pair of which I here found fossil; for as these insects never inhabit sea-water, but live only in fresh water, the circumstances of the case point to just such an inflowing river-stream at this place. The con- dition of the organic remains bears evidence to this former distribu- tion of land and water at this place. In such an arm of the sea with a river flowing into it, the sea-plants would have been here and there drifted to shore, together with masses of land-plants and the animals that had perished in the water, where they must have lain im great confused heaps promiscuously washed up. And indeed in suchwise do © we meet with them on the afore-mentioned slabs of stone, which dis- play just such confusedly-arranged and drifted masses of plants and animals. | The organic remains do not occur under such circumstances at Cningen. It is only the larvee of Lzbellule that we here sometimes meet with in great assemblages, which however are only such as those in which these animals are found living at the bottom of the existmg ponds and ditches. And hence we have an additional proof that at (Eningen a small quiet lake existed, the water of which was subject only to trifling motion. 4, A fourth point worthy of consideration with respect to the fossil Ants is the great abundance of the individuals. From Radoboj and HEER ON FOSSIL ANTS. 63 (Eningen together I have examined 279 specimens, belonging to 55 species: from Ciningen 158 specimens of 28 species; from Radoboj 119 specimens of 34 species. All the existing species of Ants, as is well known, present astonish- ing swarms of individuals. We have in Europe only about 40 species of Ants, and yet these creatures are amongst the commonest of insects that in summer enliven hill and valley. This proportionate abun- dance indeed existed also in the ancient world. On account of this abundance of individuals, it is easy to collect individuals of the species that have lived at Radoboj and Giningen ; and hence we may consider these 28 species from Ciningen and 34 from Radoboj as tolerably well representing all the species of Ants then existing at these places ; and we may be said to have before us a tolerably perfect collection, from these localities at least, of the Ants of that period. Indeed we may come to a further conclusion ; the Ants have always a very wide extension, and most of the species living with us are found throughout Europe. These 55 fossil species, therefore, may generally and more or less perfectly represent the Ants of Tertiary Europe. 5. The Ants are of importance in the fifth place, in that they readily afford us the most numerous data for the comparison of the (Eningen and the Radoboj faune. Both belong to the tertiary epoch ; still it is not precisely determined whether they were quite contempo- raneous or otherwise, and this question can be solved only by a strict comparison of the plants and animals of both localities. Of Coleo- ptera, Radoboj and Giningen have only one species in common (Tele- phorus tertiarius), of Hymenoptera also only one (Termes pristinus), and of Orthoptera none. We must remember that these forms occur at Radoboj only as a very few species, and that we are as yet ac- quainted with a much smaller number of insects from Radoboj than from Giningen. On the other hand both localities, as we have already seen, are very rich in Ants. Of the 34 species from Radoboj there are only seven that occur also at Ciningen, being about + (the pro- portion of Coleoptera being {3;, and that of Hymenoptera t). We must here also notice, that among these 34 species there are eight which, beg males, can probably be placed in the other species (fe- males), and consequently there remain only 26 species. Of the seven species that are common to the two localities, one is lost for the same reason, reducing the number to six; and thus not quite one-fourth of the whole number of the species are common to Radoboj and CEnin- gen, which may be considered as an evidence of the contemporaneity of the two faune. We have to bear in mind that Radoboj lies near about 7° more easterly and 2° more southerly than Ciningen, and that from this cause the existing fauna and flora of these localities differ considerably one from another, Radoboj having a more southern character ; and the same is the case with regard to the fossil charac- ters of this locality. The family of the Ants increases at the Tropics to very numerous species, and there occur in warm countries some peculiar genera, as Atta and the large Ponera. ‘These genera are found also at Radoboj, and indeed it is here that they appear for the first time, but they do F2 64 GEOLOGICAL MEMOIRS. not occur at Giningen ; and Radoboj has absolutely a greater number of species of Ants than Giningen, although Giningen is richer m other msects, and although Giningen Ants are much more frequently found in coliections. The above goes to prove the more southern character of the Radoboj fauna. With this the flora also agrees; for at Radoboj three species of Palm (Flabellaria maxima, Unger, Fl. Freyeri, Unger, and Phenicites spectabilis, Unger), a Smilax, and a Ficus, occur im connexion with other southern forms. The extinct fauna of Giningen is of a more southern character than what obtains at @iningen at the present time, and comes nearest to the existmmg fauna of the Mediter- ranean ; but that of Radoboj is yet more southern, and mdeed appears to be somewhat subtropical; but this also may be explained by the more southerly position of the district. 6. This brmgs us in the sixth place to a comparison of ‘the fossil with the existing Ants; and here I will confine myself toa few im- portant points. First of all I would observe, that the genus Myrmica, which plays an important part in the existing fauna, some of its spe- cies being the most abundant in the whele family, is but feebly deve- loped in the fossil state. I have met with only 26 specimens (22 from Giningen and 4 from Radobo}) belonging to 8 species. It was therefore at that time less plentiful, particularly at Radoboj, than at present. On the other hand it occurs in two strikingly beautiful, large species, Myrmica macrocephala and M. tertiaria. The latter of these was widely spread, since it 1s found at Giningen, Parschlug in Steiermark, and Radoboj}. The former, on the contrary, occurs only at CEningen, but there it was the more plentiful species; it ap- pears for the most part to agree with Myrmica barbara, Fabr., of North Africa. The genus Atta, as before remarked, occurs only at Radoboj, and is represented by three, or if we deduct a male, by two species. One of these resembles in general form and in the venation of the wmgs the singular dtta cephalotes, Auct., which is plentiful in tropical America, and there often penetrates in great swarms into the dwell- ing-houses, and destroys all vermin, as flies, bugs, &. The other species may be compared with Atta destructor, Latr., occurring im the south of Europe, which inhabits sandy places, and constructs an entrance to its habitation in the shape of a tube or tunnel formed of sand. The whole genus, with the exception of a single species found in the south of France, is extra-Kuropean, and more particularly foun in the warmer parts of America. Of the genus Ponera one species (P. contracta, Latr.) is frequently found with us, but it is a small, insignificant species. The warmer parts of America, on the other hand, afford a number of fine, large species. Three species occur at Giningen, Radoboj, and Parschlug, which for the most part remind us of these tropical forms, and one of which appears to be closely related to Ponera apicalis, Latr. By far the majority of the fossil Ants belong to the genus Formica. This is divisible into two groups; im the one there is but one discoid areola [ Discoidal-zelle] in the venation of the wing, and im the other there are two such areole. They differ also in their mode of living’; MONHEIM ON CALAMINE AND CALC-SPAR. 65 the first living in small societies in dry trunks of trees, from which circumstance they may be termed Wood-Ants, whilst the others live for the most part in the earth and under stones, or construct their habitations of little fragments of plants. The former predominate in warm countries, the latter in temperate and cold climates. It is worthy ef remark, that nine species of these great Wood-Ants occur at Radobo} and Giningen (the latter having eight and the former four species): . One of these, Formica lignitum, Germar, is very similar to our Lormica herculanea, Latr., inhabiting the trunks of the pine and fir, and, probably lived in the trunks of the cypress of the ancient (ningen forests... This species is found also in the brown-coal of Bonn. The second, F’. gravida, corresponds to fF’. ethiops, Latr., that lives in Central Europe. And for the remaiming members of this group I cannot find analogous living species. With regard to the Ants of the second group, I will mention, that one, I’. Thetis, is sumilar to J. rufa, which is so plentiful with us in woods, and here constructs great conical heaps of fir-leaves and frag- ments of wood; another, /. ophthalmica, corresponds to the Black Ant, I’, nigra, which is widely spread throughout Europe. | [T. RB. J.] Pseudomorphosis of CALAMINE and Cauc-spar from the SrvERIN Mine, in the neighbourhood of Nir, near A1x-LA-CHAPELLE. By V. Monue rm. [ Verhandl. d. Naturhist. Vereins der Preuss. Rheinlande, 1849, V. p. 33, and Leonhard u. Bronn’s Jahrb. f. Miner. 1849, p. 862.] In breaking a large piece of blende there was found in the inside a druse-cavity, in which at one spot small, but very regular crystals of galena occurred, also minute crystals of iron pyrites, and many other crystals of a yellowish white colour, which were either combinations of the more obtuse calc-spar-rhombohedron with the six-sided prism, or had besides flat extremities. These crystals were situated on the blende, the iron pyrites, or the galena, and were either quite hollow, or their interior was occupied by innumerable, infinitely small, regular forms of the same substance. Their chief constituent was, according to our analysis, carbonate of the oxide of zinc ; but they contained also a large per-centage of the carbonate of the oxydule of iron, some carbonate of lime and car- bonate of magnesia. Amongst these hollow crystals were situated a few, somewhat elevated, white crystals of a stmilar shape, which were evidently to be regarded as calc-spar. Hence we are warranted in concluding that the above-mentioned hollow crystals must be crystals of calc-spar transformed into zinc-spar (calamine), or, more correctly speaking, iron-zinc-spar. They might have been formed thus: water impregnated with carbonic acid and contaiing in solution carbonate of the oxide of iron, together with some carbonate of the oxydule of iron and a little carbonate of magnesia, came into contact with the calc- 66 GEOLOGICAL MEMOIRS. spar crystals, and, taking up the much more soluble lime, allowed the less soluble carbonate of zinc to separate itself and be deposited, together with some of the other carbonated salts, in the place of the isomorphous carbonate of lime, the crystals thus formed having the appearance of large perfectly developed zinc-spar crystals; some, however, with rough surfaces, as if a mass of small zine-spar erystals was covered with regular cale-spar crystals. [T. B. J] On the Foss1u Woop collected during M1ippENDOR¥’s TRAVELS im SIBERIA. By Prof. Goprert. [Sibirisch. Reise, I. i. 10, pl. 7-10, and Leonhard u. Bronn’s Jahrb. fur Mineral. u. s. w. 1850, pp. 126-128.] From the Tundra to the river Boganida in 71° N. lat., the fossil Pinites Middendorffanus, Gopp. (pl. 7. figs. 1-4) *, oecurs ; the wood is permeated by carbonate of lime; the structure is similar to that of the existing Pines. From the banks of the river Taimyr m 74° N. lat. three species are obtamed. The characters of one spe- cies (pl. 7. figs. 5-17 and pl. 8. figs. 15, 16) are rendered indistin- guishable by reddish brown oxide of iron; it is very similar, both in outward appearance and in the thickness of the annual rings, to some fragments from certam deposits at Berlin and im Silesia; an- other, converted into shining black coal, is the P. Baerianus, Gopp. (pl. 8. figs. 12-15); and the third (pl. 8. figs. 17-20), silicified and haying the appearance of a greyish brown hornstone, is so much weathered, that nearly all the organic tissue between the siliceous casts of the cells has disappeared; hence no specific determination can be arrived at. On the banks of the river Taimyr, in 75° N. lat., two fragments of wood were found in the immediate neighbourhood of a skeleton of a mammoth, and apparently under similar geological conditions. These were but slightly changed ; they had the appearance of having been for a long time in the water, and their specific gravity was less- ened. One of the specimens is identical with larch-wood (Laria Europea, L. Sibirica, L. pendula, L. microcarpa, and the fossil Pinites protolariz, Gopp.), and cannot be specifically distinguished ; whilst the other is identical with fir-wood (Pinus abies or picea, Abies Sibirica, Pinus picta, and others). . None of the above fossil woods are apparently older than the ter- tiary formation ; and the last two (subfossil) species, found near the mammoth, are indistinguishable from the existing larch and fir spe- cies of Siberia. The place where they were found, however, is far to the north of the districts occupied by the existing species ; they must therefore have been carried by river floods, probably in company with the mammoth, from more southerly districts to the spot where they were found. , * The plates do not accompany this translation. GOPPERT AND MIDDENDORF ON FOSSIL WOOD. 67 Middendorf adds, that Goppert, in examining this fossil wood, has arrived at the following conclusions, which coincide with the views that he himself was led to take by observations made on the spot : namely, that all the fossil wood and coal as yet found in the Taimyr country dates from a very recent epoch of the earth’s history. That the fossil wood of Northern Siberia belongs to the existing flora, and resembles the drift-wood that is at the present day washed up by the waves on the northern coast. ‘That this fossil wood, both on the lower part of the river Taimyr, as also in the districts near its source, occurs far beyond the northern limit of the growth of trees, especially of fir forests. That in its organization and state of preservation it quite agrees with the drift-wood still washed up by the sea. That well- preserved and unworn marine shells, of species still existing in the Arctic sea, occur in the same beds with the fossil wood. And that, therefore, the fossil wood probably found its way to the Arctic sea by the same course as that traversed by the drift-wood of the present day, which is brought down to the sea from central and southern Siberia by the large rivers, particularly the Jenisei and the Lena, and after drifting about for some time, is stranded on the coast. That the Tundra was at that time the bed of the sea is proved by the im- bedded shells, the shingle, and the erratic blocks. That the Arctic sea as well as Southern Siberia already possessed at that time a cli- mate like the present, is proved, on the one hand, by the marine shells of recent species, and on the other by the species of the fossil wood. That, lastly, the Mammoth found at the Taimyr participated with the fossil wood in the circumstances of its fossilization ; and that, to- gether with the wood, it was brought down to the sea from its native locality near the upper (southern) parts of the Siberian rivers ; that the low temperature of the rapid rivers and a covering of ice for a time favoured its preservation, until it was silted up on the sea-coast, where ultimately its decomposition formed the layer of mould, evi- dently of animal origin, that was found to envelope the skeleton *. Middendorf observes that this animal, possibly, like the elk of the present day, was enabled by the peculiar structure of its teeth to feed on the twigs of the fir; in which case it did not suffer want of food. Middendorf had frequent occasion to wonder at the astonishingly long period during which the carcases of animals washed up on the shore of the Arctic sea are preserved. Even a stranded whale, thrown up on a sandy shore by strong breakers during an ebb tide, becomes quickly imbedded; its blubber, however, remaining fresh and well-preserved for a considerable time afterwards ; whilst a car- case thrown up high on shore by a flood-tide is left exposed on the surface, andis quickly consumed even to the strongest bones by beasts of prey. With regard to the mineralized and carbonized woods of the first- mentioned locality, Middendorf gives up his opinion of their being of the same species as the subfossil woods subsequently described ; * (Compare the chapter on the Mammoth Period, Murchison’s Russia and the Ural, pp. 492-506.—Ep. ] 68 GEOLOGICAL MEMOIRS. but apparently insists that the former also were deposited as drift- wood in the locality where they are found, and became mineralized subsequently. [T. BR. J.] On the History of Insects. By Prof. O. Heer. [Leonhard und Bronn’s Jahrb. f. Miner. u. s. w. 1850, pp. 17=33.] Tue great Class of Insects, which furnishes four-fifths of the ex- isting species of the animal kingdom, has two chief divisions. In the one (the Ametabola) we have an imperfect, in the other (the Metabola) a perfect metamorphosis ; that is, in the former there is ‘no -~- quiescent pupa-state, and the metamorphosis is accompanied by ne striking change of form; in the latter there is an mactive ‘pupa, that takes no nourishment, and so great a change of form that only by watching the progress of the metamorphosis can we recognise the pupa and the imago as being the same animal. The Metabola correspond, as it were, to the flowering plants; the Ametabola to the Crypto- gamia. It is well worthy of remark, that among Plants the Crypto- gamic, and among Insects the Ametabolous, first appeared upon our earth. The most ancient forests, composed of tree-ferns, elub- mosses, and equiseta, were inhabited by Locuste and Blatte, the first of insects. There have not as yet been found in the carboni- ferous and triassic rocks any traces of insects that can be with cer- tainty referred to any of the other Insect-orders. And of these Orthoptera at present we know of only six species belonging to these most ancient times, in which indeed insects appear to have been ex- tremely scarce. Nor need we wonder, if we consider that at present also our Lycopodia and Equiseta harbour no insects, and the Filices very few. ‘The hosts of insects, therefore, that live on the flowers and their honey, on the fruits and seeds, could not at that time have been in existence, the vegetable world being then destitute of flowers and fruits. The ametabolous insects also play the chief part in the jurassic period. Here they appear as very large Locusts and Dragon-flies, the latter belonging to the Zschnide * (including the Gomphz) and the Agrionide, as a few Termites and a long series of beaked insects. Near these, however, in the jurassic rocks occur also some insects of the second division ; namely, a few Flies, an Ant +, and a number of Beetles. The flower-insects, on the other hand (as Bees and Butterflies) {, appear to have been wanting at this period. This is also the case in the succeeding period, that of the Chalk, * The Libellula Brodiei, Buckman, in Brodie’s ‘ History of the Fossil Insects in the Secondary Rocks of England,’ is clearly an 4schna. + I look upon the Apiaria lapidea, Germar, to be an Ant, on account of the peduncled hind-body. In its bearing also it much more resembles an Ant than a Bee. } The Tinettes lithophilus, Germar (Munster, v. 88), is according to my view a Termite. Not only on account of its size can it not be a Moth, but still more on *“sy2a4 ~* alg PIe aan /E HEER ON THE HISTORY OF INSECTS. 69 in which neither Butterflies, nor Bees, nor Hymenoptera generally have been found. The Beetles, on the other hand, occur in some- what larger proportion. In this cretaceous period there existed islands rising from the sea and chiefly wooded with fir-trees ; bearing also Palms, Dragon-trees, and tree-like Lilies, together with which the first dicotyledonous trees occur. These, however, appear to have been as yet very few in number, it being only in the followimg period, the tertiary, that they became plentiful, forming from this time an essential proportion of the vegetable kingdom. In company with the creation of dicotyle- donous trees and phanerogamic herbs, the Insect-world appears to have been first developed at this period in all its orders and in more manifold forms. Whilst at present we are acquainted with only 126 species of insects altogether from the earlier geological periods; from the two tertiary localities Giningen and Radobo} I know of about 443 species. Amongst these are present all of the seven Orders of recent Insects; but, nevertheless, in different numerical proportions to those of the existing faunze. In these the Ametabola form about 0:10, the Metabola 0:90. Of the Ginmgen and Radoboj species, 124 belong to the Metabola and 319 to the Ametabola; the former making more than a third. We see therefore that at this period the Ametabola were much more numerous in proportion than the Meta- bola, although not more in the mass, as in former geological periods. The Bees and Butterflies appear as new chief types, presenting however only very few forms. In the existing creation only have these Insect-types been developed im their full richness of form and splendour of colour; and this may be the better understood inas- much as in the tertiary period the land was almost entirely occupied with woody plants and forests, and offered but few herbaceous flowering plants from which the Butterflies and Bees could derive their nourishment. With regard to each of the Orders of Insects, the material we have at present is much too limited to enable us to give a perfect history of this great Class; nevertheless we are enabled to offer a few hints on this hitherto little-known subject. I. Among the Ametabola we meet with the beaked Insects in nu- merous families. In the jurassic period appear some large water- bugs [Wepide, &c.|, some land-bugs | Cimictde], and Cicade. Inthe cretaceous period appear Aphides, and in the tertiary period there are very beautiful Cicade and large species of Cercopis, which are characteristic of this Rhynchota-fauna | Hemiptera]; there are present account of the short thorax, and legs destitute of spines, in which respects it agrees with the Termites, as well as in the long, narrow, fork-veined wings, folded over the body. Il also regard as a Termite the Apiaria antigua, Germar (Nov. Act. xxii. 2). The venation of the wings at once shows that this animal cannot pos- sibly belong to the Bees; on the contrary, most probably it is referable to the Termites. The wings are not well-preserved in their whole length, hence their apparent shortness. The fossil from Solenhofen, figured as Sphinx Schreteri (Schroder, Neue Literat. I. Taf. iii. 16), is so badly drawn that nothing can be done with it. 70 GEOLOGICAL MEMOIRS. also numerous species of Bugs, which are very similar to existing species. "OF the second great order of ametabolous Insects, the Gymno- gnatha | Neuroptera, &c.|, I have particularly to notice the Libellule and the Termites, both which families have a high geological import- ance. ‘They commence early in the jurassic period, and have continued throughout the cretaceous and tertiary periods down to the present, although now they no longer play the part they formerly did. The jurassic Libellulhde are all large, beautiful animals, and are all Aischnide or Agrionide ; true Inbellule occur for the first time in the chalk. Near to the genus M#schna come Gomphus and a peculiar genus Heterophlebia, observed as yet in the jurassic rocks only. The Agrionide, which are much scarcer than the Aischnide, belong for the most part to the group Lestes, characterized by many fine areolee in the reticulations of the wings. A peculiar group, Sterope, also occurs in the has and is again found at Ciningen, but has since be- come extinct. In the tertiary period there existed, besides the genus Sterope, other members of the Agrionde, particularly species of iLestes; and species of Avschna very similar to existmg forms were present, and Lzbellule proper. These were so plentiful at Giningen, that their larvee were amongst the most common animals there. It appears therefore that in this family the ischnide and Agrionde first occurred ; and of the latter the many-celled-winged [vielzelligen | before the rest. Further, the genus Lzbellula, at present so rich m species, first appeared in the Chalk period, and was developed in numerous species in the succeeding tertiary epoch. Still more re- markable, however, than the Libellule are the fossil Termites, those smgular animals that are at present so abundant in the Tropics, con- stituting one of the greatest land-plagues of hot countries. Like the Ants they live in large communities, building themselves curious habi- tations, and feeding on vegetable matter. The Termites (two spe- cies) appear first in the jurassic, and subsequently in the cretaceous and tertiary beds. I am acquainted already with nine species, the majority of which are remarkable for their size ; one species is larger than any one of the existing species. The Ter mites are most nu- merously found at Radoboj; and I know of two species from Cinin- gen and three from amber. Some of these tertiary Termites resemble Brazilian species, but the majority exhibit peculiar, extinct forms. Their size and their great abundance allow us to infer the existence of a rich vegetation in the demolition of which they were necessarily occupied. That the Orthoptera comprise the oldest known insects has been already mentioned. It is important to observe that the Blattide first appeared in the carboniferous epoch, and have continued through all subsequent periods down to our own time, and indeed in very similar forms. The same may be said also of the Acredi and the Locusta, with which the Locust-type commences, continuing down to the pre- sent. Most of the tertiary Locusts belong to the @dipoda, but there also occurs the genus Gryllacris, still living in India. II. Of the Metabola we first meet with the Fhes. At present these HEER ON THE HISTORY OF INSECTS. 71 occur in nearly the same numerical proportion as the Hymenoptera ; the latter, however, are somewhat richer in species. The Flies had the same proportion in the tertiary period also. I am acquainted with 80 species of Diptera and 87 of Hymenoptera from Radoboj and CEningen*. ‘The order of Diptera comprises two great natural divisions—the Nemocera |[langhérnigen| or gnat-like Flies and the Brachocera. At present the first form about + and the latter 9 of the species; there are known 1161 of the Nemocera and 7100 of the Brachocera. The Nemocera were the first to appear, and were fol- lowed a little later by the Brachocera, which at Giningen form only 4, at Radoboj about 4, at Aix also about 4, m the amber about 4, whilst at present, as above remarked, they constitute § of the Di- tera. The fact that, in all localities from which we have as yet obtained fossil Flies, the Nemocera so decidedly predominate, clearly proves that this proportion was not dependent on local causes, but that the Nemocera were indeed the oldest amongst the Diptera. With this also corresponds the fact that all the known Flies of the cre- taceous age (15 species) belong to the Nemocera, not any to the Brachocera. The few specimens of Flies from the jurassic rocks with which we are acquainted are unfortunately so badly preserved that no correct determination of their characters can be arrived at. Nor is it very difficult to suggest a reason why the gnat-like Flies [ Nemocera] were the first to appear, and have down to the present time formed the majority of the Fly species. The Brachocera live chiefly on flowering and herbaceous plants; we see them m crowds basking on the flowers of the umbelliferous and syngenesious plants ; on the contrary, the Nemocera fly about in woods and thickets, and particularly affect damp, watery places. Their larvee live partly in water, partly in damp woody bottoms, im rotten wood, and in great numbers in fleshy fungi; whilst the larvee of the majority of the Bra- chocera inhabit different flowers, fruits, seeds, and. roots, especially of herbaceous plants. Everything, however, points to the fact that in the tertiary period the land was occupied chiefly by tree-like plants ; and further, the many species of willow and poplar, as also the swamp cypress (Taxodium), point to extensive swamps and morasses. If we imagine a widely-extended dark damp wood, traversed by small streams and interrupted by morasses, we have altogether the condi- tions requisite for the gnat-like flies. Of the fossil Memocera dis- covered at Giningen and Radobo}, three have lived as larve in the water, and ten in fleshy fungi; we may therefore feel assured of the occurrence of such fungi in these ancient woods, although as yet no fossil remains of them are known. There were 47 species also of Flies, and that too the majority, living without doubt in damp woody grounds and rotten wood. Such damp woodlands were very pro- bably also the favourite resorts of the numerous Pachydermata of * T would remark, for those who possess my work on the Insect-Fauna of the Tertiary Formation of Radoboj and Gningen, that since its publication I have met with a considerable number of new species, which will be described in a supplement. The numbers given in the present memoir refer to species known to me down to August 1849. 72 GEOLOGICAL MEMOIRS. that age. The Tapirs and wild swme are still met with im such localities ; and these, as also the Elephants, Mastodons, Rhinoceroses, and some subordinate similar species, belong to the most plentiful — and most widely-spread of the higher animals that during the ter- tiary time inhabited the dark forests of our countries. Of the Diptera, the larvee of which lived in the earth,’ there ‘are the Bibiones, which occur mm an astonishmg abundance: Iam ae: quainted already with 34 species of such Bidionide, whilst at present; from the whole of Central Europe, only 44 species are known.*: It is here worth noticing, that of those 34 species, 22 only are included in the genus Bibio (of which there are as yet known only 18 Euro- pean and 11 American species) ; 2 species belong to the’ Brazilian genus Pleceia, and 11 species to two newly instituted, peculiar, ex- inet genera. I was surprised also to find amongst the Aix-la-Cha- pelle fossils one of these new genera, that occurs also at Radoboj, at (ningen, and in the brown coal of Orsberg, the genus Bz6i0 bemg there well-represented. We see, therefore, that the Diptera of the tertiary epech culminate in the group of Bbionide. 1 have not found in a fossil state any Thorn-gnats [ Olitellarie?|, Gad-flies [| Ta- banide |, or flies parasitic on warm-blooded animals, and these probably belong only to the existing fauna. On the contrary, Aselide occurred, which chase other flies and suck their blood; and this mode of life; without doubt, obtained at that time. It has been already mentioned that the Butterflies occurred at a later period only, and were but few in number even in the tertiary period. On the whole I am acquainted with only 7 species from Radoboj and 2 from Ciningen; and there are only a few species known from Aix-la-Chapelle, and a few from amber. It is remark- able, that of these Lepidoptera, two species have great similarity with East Indian species, whilst one is comparable with our Thistle-butter- fly and one with our [Gras-Sacktrager |. If we glance at the Hymenoptera of the ancient world, we shall be struck with the astonishing abundance of Ants in the tertiary epoch, I am acquainted with 66 species from Ciningen and Radoboj; there are many also at Aix-la-Chapelle and in amber; the number of the tertiary species of Ants thus amounting to almost a hundred. If we consider that at present we are acquainted with only 40 European species of Ants, this fact of the richness of the species will be very surprising. And the more remarkable it is, since nearly all the existing genera are found amongst the tertiary Ants; and there occurs moreover a peculiar extinct genus (Imhofia, Heer); thus the Ant-type m the ancient world appears to have been developed in much richer forms than at present. The Ants were particularly abundant at Radoboj, where they compose the majority of the fossil animals. That locality affords stones that are quite covered with Ants ; and indeed often as many as six different species are found lying confusedly together on the same slab. What a richly luxuriant vege- tation must have here existed to have supplied nourishment for such hosts of Ants, so many Termites, and Locusts ; and what living multi- tudes must these ancient countries have produced ! Whilst the ter- HEER ON THE HISTORY OF INSECTS. jo tiary forests, locally at least, must have swarmed with Ants, the other families of the Hymenoptera, on the contrary, very sparmgly occurred. Of the fossorial Wasps I have as yet met with two species only, and of these one exhibits a remarkably gigantic form. Of the Ichneumonidae, which at present form the majority of the Hymenoptera, | am ac- quainted with only nine species. This is analogous to the scanty development of the Lepzdoptera. Very many Ichneumon-flies are connected with this order of imsects, since in their young state they imhabit the body of the caterpillar in which they have been de- posited. .At this period there existed very few Butterflies, there could, therefore, be only few Ichneumon-fiies ; hence we may ob- tain .a confirmation of our former supposition, that the Butterflies belong to a later period of creation. It is also worthy of remark, that besides the Ichneumon-flies proper, there occur also in the fossil state some species that have lived in the interior of the larvee of the same. Thus, the species of the genus Hemiteles pierce, and lay their eggs in, the larvee of the Ichneumon-flies, which mhabit the bodies of caterpillars. This genus Hemiteles is represented at Radoboj by one species; this remarkable and complicated. relation therefore existed already in the tertiary period. The Bees, the Leaf-wasps [Cynipide|, and Wasps proper, like the Ichneumon-flies, are not numerous; and in comparison with the Ants, are quite in the back- ground. Of the Wasps proper I know of only one wing from Parschlug in Steiermark; of Bees, one Humble-bee species, some Flower-bees, and one very fine Wood-bee.- Of the great Coleopterous order of Insects the vegetable-feeders first appeared. The Weevils [Curculionide|, Goat-chafers [ Ceram- bycide|, and the Sternoa: | Buprestide and Llateride| predominated in the jurassic period. In the cretaceous period the Curculionide, Sternoxi, and Palpicornes are the most numerous. In the tertiary period the Sternowxi hold the first rank, then come the Weevils, the Lamellicornes, the, Leat-chafers | Melalonthide], the Clavicornes, the Palpicornes, and Ground-beetles | Carabide|. We must notice that of the Sternoxi there are in particular the Bupresées [| Pracht-kafer |, the most important member of this group throughout the former geo- logical periods of the earth. These Buprestide we find first in the jurassic rocks, then in the chalk, and as a multitude of fine large species in the tertiary strata. How differently conditioned is our fauna in this respect! We have some few small and insignificant species, whilst the tropics harbour a multitude of species remarkable for size and beauty of colour. The fossil Buprestes without doubt inhabited the woods, just as the existing species, and their larvee lived in the interior of trees. The Goat-chafer [Cerambyx] appears to have been the most abundant throughout the whole of the tertiary times, whilst with us at present the Bostrichide furnish the majority of the wood-destroying Chafers. In the tropics, however, the Ceram-~ éyces occur still more numerously in the forests than the Buprestes. The Cerambyces, which, like the Buprestes, are wood-eaters, were very rare in the tertiary period, as well as the Bostrichide ; we can- not, therefore, attribute the great abundance of the Buprestes to the 74 GEOLOGICAL MEMOIRS. luxuriance of the forest vegetation ; but other important cireum- stances must have co-operated in the development of the fauna and flora generally, and especially m that of the Coleoptera. The Bu- prestes, therefore, are interesting in a geological poimt of view, enter- ing into creation at an early period, predominating amongst the Woods chafers in the tertiary period, and occupying an important plaee im the history of the development of the Beetle-tribes. | What the Buprestide are amongst the land-beetles, the Hydrophi- lide are amongst the water-beetles. Our waters are inhabited by two chief Beetle-families, the Hydrocantharides and the Palpicornes. At present the former predominate, and indeed not only with us, but also in the hotter countries. In the tertiary period, on the other hand, the Palpicornes decidedly predommated, and that especially through the Hydrophili. Not only do they occur im a long series of species, but also in gigantic and remarkable forms, unmatched by any living species ; indeed one very peculiar genus (Escheria) is be- come altogether extinct. That this predominance of the Palpicornes was not dependent on local causes, will be shown by the faet, that as yet there are known four species of Palpicornes and only one Hydro- cantharis from the chalk, three species of Palpicornes with one Hy- drocantharis from the jurassic beds, and that at Ciningen and Ra- doboj together about twice more of the former than the latter oceur ; whilst, on the contrary, in the present world, were we to compare the relative proportion, either generally or in the Swiss fauna, there are known about twice more Hydrocantharides than Palpicornes inhabit- ing the waters. In fine, the water-beetles, as also the land-beetles, have commenced with the more incomplete forms—the vegetable- feeders, and only at a later period were the more highly organized carnivorous water-beetles brought into existence. From this examination of the history of insects arisés the question*, Is there naturally a development of the perfect from the imperfect, or is the introduction of different plants and animals entirely influ- enced and guided by external circumstances, by climate, and by local conditions ? These latter circumstances are doubtlessly of the highest importance. But we also see that similar climates produce altogether different forms, as a comparison of the natural history of North Ame- rica and of Europe, or of districts even lying nearer together, will show us. Hence we see that climate is not the only determinating condition, and that typical differences exist under similar climates ; a harmony, at the same time, existing between the plant- and animal-types and the climate in which they live. Taking mto consideration the influ- ence of external circumstances, we are prepared to expect that aquatie animals and plants must necessarily have been the earliest organisms, * With great pleasure I find the author, altogether independently and of his own accord, by the examination of fossil insects, arrive at similar conclusions with regard to the laws of the development of organic nature, to such as, from the study of fossil remains, I have given in the ‘ Geschichte der Natur, Abtheil. Enu- merator Palzontologicus ;’ viz. (1.) the law of gradual perfection in its peculiar modification, governing through (2.) the law of progressive relation of organiza- tion to external conditions ; thence (3.) the law of increasing diversity.—Bronn. HEER ON THE HISTORY OF INSECTS. 79 in consequence of the predominance of the primeval ocean; and we find also, that these inhabitants of the water in general have a lower grade of organization than the land plants and animals. Thus it is evident that both of the great organic kingdoms of nature have pro- duced their lowest, and at the same time their earliest, forms in the water. As dry land arose, so also must have arisen new conditions favourable for the existence of a multitude of new plants and ani- mals ; and that so much the more, the more the firm land increased in extent and in heterogeneousness of composition. And, in accordance with the conformity existing between the extent of the inorganic and the organic relations of the earth, the evolution of the more and more varied conditions of climate, soil, &c. would be steadily accompanied by more and more manifold forms of animal and vegetable life. Evidence of this progressive change is to be seen in the case of In- sects; and is especially shown by the above-mentioned relative pro- portions existing between the Metabola and the Ametabola; the latter, of inferior organization and with imperfect changes, appearing first on the stage, and, in the early periods of the earth, predomi- nating over the former. There being no marine insects, this animal type could first come only with the formation of dry land. Of the Articulata, to which class of animals the Insecta belong, the subor- dinate Crustacea first appeared, predominating, through the Trilo- bites, in the earliest geological periods *. There are also some striking examples, previously given, in the in- dividual orders of Insects, of the appearance of the more imperfect forms before those of higher organization. The Hymenoptera and the Diptera, however, appear to form an exception. If in the Di- ptera we begin with the Brachocera as the more imperfect, and ascend from them to the Nemocera, we ought in the Hymenoptera to place the Bees lower than the Ants and the Ichneumon-flies. This arrange- ment certainly does not seem natural. The Bees appear to me to belong to the head of the Hymenoptera, and the Ichneumonide to occupy a subordinate rank. The Muscide, among the Diptera, are analogous to the Bees, but the Ichnewmonide have as their analogue the Nemocera, so that the latter appear to stand lower than the former, and this is supported by their more imperfect wing-structure. Under these considerations, the Hymenoptera and the Diptera would not altogether contradict the general rule, that the earth, both in the formation of its surface and in all its habitants throughout the course of time, had received continual improvements............... A second important conclusion that I believe may be drawn from the above inquiry into the history of the Insects is, that the older an animal type is; so much the more are the tertiary related to the ex- isting forms of that type}. Each type also commences with peculiar forms, and then gradually approaches to those of the present time. The Vertebrata clearly show this; of these, the fish first appear * [Compare Prof. Agassiz’s ‘‘ Geographical Distribution of Animals,” Christian Examiner, 1850, p. 190. —Ep.] + This is authenticated, both generally, and among Mammalia in particular, in the ‘ Geschichte der Natur, Enumerator.’ 8. 739 ff., 909 ff., 936 ff.—-BRronn. 76 GEOLOGICAL MEMOIRS. with forms most foreign to those now existing, whilst the tertiary fish are very similar to recent forms. The Mammalia occur first in the tertiary period, in any force at least, and commence as new classes of animals with very bizarre forms. Thus, the mammals of compara- tively late introduction are so very different from existing forms, whilst the contemporary fish, representatives of a far more ancient type, are with difficulty discriminated from their recent allies. This also holds good with Insects. The tertiary Libellulide, Locustide, Blattide, Mycetophile, Tipule, Limnobie, &e. are very similar to existing species, and at the same time belong to types that occurred at an early period, and have passed down through many subse- quent epochs. The Protactide and the Bees, on the other hand, appearing in the tertiary age, exhibit very singular forms. Thirdly, the oldest animal types of the present world appear also to have the widest extension on the earth*. The limit, therefore, of the dispersion of existing beings may afford at least some geological hints. As examples, I will mention that the Fungus-flies appear early in the jurassic rocks, and that of these, one species (Myceéo- phila pulchella) occurred in the tertiary age, to which one species found throughout Europe (M. 4-notéata), and another found in North America (M. cinetipes), have great resemblance ; also, that of the genus Syrphus, a tertiary species is very similar to S. scalaris, which is spread throughout Europe, a part of America, and Asia; and that tertiary species of Limnobia occur which stand extremely near the widely spread existing species; &c. But however similar the fossil Species appear to be to the recent, they are, without exception, quite distinct ; and the whole insect-fauna of the tertiary epoch is extinct ; its fragments only, preserved to us by the rocks, give us a knowledge of the peculiar life of the ancient world. [T. R. J.] eee, Ss On the COAL-FORMATION near Merisporr in the SELKE VALLEY. By Herr GiEse.. [Sitzungs-Protok. des naturwiss. Vereins in Halle, i. 1848-9, p. 29, and Leonhard u. Bronn’s Jahrb. f. Min. 1850, p. 91.] Tnis formation, like those of Wettim and Lobejun, had been hi- therto referred to the New Red Sandstone. The trial-shafts, however, in the Selke Valley have furnished the following characteristic plants, that remove all doubt of these beds belonging to the true coal-for- mation ; viz. Pecopteris arborescens, P. abbreviata, P. Oreopterides, P. polymorpha, Sphenopteris artemisiefolia, Neuropteris hetero- phylla, N. auriculata, Annularia longifolia, Lycopodites Bronnz, &e. Toe a * [Count D’Archiac, M. De Verneuil, and Prof. E. Forbes have also enunciated the fact, that the fossils common to the most distant localities are such as have the greatest vertical range. Edinb. New Philos. Journ. vol. xxxvi. p. 323.—Ep.] ALPHABETICAL INDEX TO THE PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [The fossils referred to are described, and those of which the names are printed in italics are also figured. | Actinocyclus ——, 332. Age of the granitic rocks of the Alps, noticed, lix. Age of the upper tertiaries in England, Mr. S. V. Wood on the, 201. Age of the valley of the English Chan- nel, Mr. R. A.C. Austen on the, 87. Alps, age of the granitic rocks of the, noticed, lix; and Pyrenees, volcanic rocks of the, noticed, xlviii; Apen- nines and Carpathians, Sir R. I. Mur- chison on the structure of the, noticed, Xxxiv; date of the upheaval of the, noticed, xxxviii; dislocations and la- teral movements of the, noticed, lvii; dolomites and gypsum of the, noticed, xlix; effects of expansion and con- traction on the strata of the, noticed, 1; erratics of the, noticed, ]xii; folded strata of the, noticed, xli; granitic rocks of the, noticed, xl; relation be- tween the strike of the strata and the axis of the, noticed, xlix; Sir R. I. Murchison on the detritus of the, 65 ; stratified formations of the Venetian, 422, Amblypterus, Sir P. G. Egerton on the genus, l. Portlocki, 2. Ammonites Reginaldi, 316. Andes, Mr. E. Hopkins on the crystal- line rocks of the, 365. , section of the, 366. Anniversary Address of the President, Sir C. Lyell, xxvii-lxvi. See also Lyell, Sir C. Annual General Meeting of the Society, proceedings at, i. Arca patricia, 52. consobrina, 52. —— Olisiponensis, 176. subtetragona, 318. Artemis cordata, 177. elegantula, 177. —— inelegans, 177. Astarte? discus, 177. VOL. VI. Astarte carinata, 317. Auckland, the Earl of, notice of, xxviii. Austen, Mr. R. A. C., on the valley of the English Channel, 69. ——, on the age and position of the fossiliferous sands and gravels of Far- ringdon, 455. Avicula Olisiponensis, 178. Basement-bed of the London clay, Mr. J. Prestwich, jun., on the, 255. , table of the distribution of fossils in the, 279. ) Bath, Mr. C. H. Weston on the diluvia and valleys near, 449. Biaritz shells, noticed, xxxv.. Binney, Mr. E. W., on Sigillaria and some spores found imbedded in the inside of its roots, 17. Blackheath, tertiary strata and their dis- locations in the neighbourhood of, 44]. Boué, M., on nummulitic rocks, noticed, XXKV. Brentford, mammalian remains at, 201. Brissus scutiger, 198. —— subdepressus, 198. Brodie, Rev. P. B., on certain beds in the inferior oolite near Cheltenham, 239. Brongniart, M. Alex., on the eocene shells of the Diablerets, noticed, xxxv. Brown, Mr. R., on the section of the lower coal-measures of the Sydney coal-field in the island of Cape Bre- ton, 115. Buckingham, section of railway cutting at, 135. Buckman, Prof. J., on some fossil plants from the lower lias, 413. Bulla granosa, 51. —— paupercula, 52. Cambridgeshire, freshwater marl in the fens of, 451. Cantal and Mont Dor, noticed by Sir C. Lyell, 234. Cape Breton, lower coal-measures of the INDEX TO THE Sydney coal-field in the island of, 115. Caprinula, Mr. D. Sharpe on the genus, 178. Caprinula Boissii, 179. —— brevis, 180.- —— d Orbignii, 180. Doublieri, 180. Cardium corrugatum, 181. —— Haitense, 52. Olisiponense, 181. Carpenter, Dr. W. B., on the structure of Nummulina, Orbitolites, and Orbi- toides, 21. Cassidaria levigata, 47. Cassis sulcifera, 47. Cataclysmal waves, improbability of the occurrence of, noticed, Ixiv. Catopterus, Sir P. G. Egerton on the genus, 8. Catopterus Redfieldi, 8. Cereopora , 390. Ototara, 329. Cerithium plebeium, 51. uniseriale, 51. Changes in the organic and inorganic worlds, noticed, xlv. Christian VIII, king of Denmark, no- tice of, xxvii. Cidaris clunifera, 196. glandifera, 196. Cleghorn, Mr. J., on the Till near Wick, in Caithness, 385. Clift, Mr. W., notice of, xxix. Coal-measures, lower, of the Sydney coal-field, island of Cape Breton, 115. Coal, occurrence of, near Erzeroom, 367. Coccolepis, Sir P. G. Egerton on the genus, 9. Columbella Haitensis, 46. venusta, 46. Comparison of disturbing causes in an- cient and modern times, noticed, xliv. of the climate of the carboniferous epoch with that of the present age, noticed, Ixv. Cones, structure and growth of volcanic, 207. Conglomerate, old red sandstone, of the Eastern Lammermuirs, 418. Continuance of existing faune during alterations of level in the Mississippi valley and in Scandinavia, neticed, xlvii. Conus catenatus, 45. consobrinus, 45. Domingensis, 45. Haitensis, 44. marginatus, 44. —— planiliratus, 44. —— solidus, 45. PROCEEDINGS. Conus stenostoma, 44. —— symmetricus, 44. Corbula Coste, 181. —— Edwardi, 181. Craters of denudation, Sir C. Lyell on, 207. Crystallization of granite, noticed, li. Cumming, Rev. J. G., on the tertiaries of the Moray Firth and the great Ca- ledonian valley, 10. Cunnington, Mr. W., on a section of the lower greensand at Seend, near-De- vizes, 453. Cupressus latifolia, 415. Cybele, Mr. T. W. Fletcher on the ge- nus, 402. Cybele punctata, 403. variolaris, 404. Cyprea Henikeri, 45. Cyprina cordata, 182. —— globosa, 182. securiformis, 182. D’Archiac, M., on active volcanos, no- ticed, xliii. ——, on the Progress of Geology, no- ticed, xliii. Darwin, Mr. C., on the British fossil Lepadide, 439. Date of the upheaval of the Alps, no- ticed, xxxvilili. Davis, Mr. J. E., on the age and position of the limestone of Nash, near Pres- teign, South Wales, 432. Dawson, Mr. J. W., on the metamorphic and metalliferous rocks of Eastern Nova Scotia, 347. Deceased Fellows, notice of, xxvii—x xxii. De la Condamine, Rev. H. M., on the tertiary strata and their dislocations in the neighbourhood of Blackheath, 441, Dentalium , ool, Denudation and oscillation of lands, great length of time required for, noticed, lv. Denudation, Sir C. Lyell on craters of, 207. Devizes, gault and greensand at, noticed by Mr. R. A. C. Austen, 468. De Zigno, M. Achille, on the stratified formations of the Venetian Alps, 422. Diablerets, M. Al. Brongniart on the eocene shells of, noticed, xxxv. Diadema Lusitanicum, 196. / —— rude, 197. Dianchora? bicornis, 183. Diceras Favri, 183. Dikes, volcanic, noticed by Sir C. Lyell, 231. Dinornis and other birds of New Zea- land, noticed by Dr. Mantell, 333. INDEX TO THE PROCEEDINGS. Dinornis robustus, feet of, noticed by Dr. Mantell, 338. Dislocations at Blackheath, Rev. H. M. De la Condamine on the, 441. and lateral movements of the Alps, noticed, lvii. Distribution of materials in the valley of the English Channel, 76. Disturbance, lines of, in Italy, noticed by Sir R. I. Murchison, 378. Dixon, Mr. F., notice of, xxxi. Dolomite and gypsum of the Alps, no- ticed, xlix. Donations to the Society, from Feb. 16, 1849, to Feb. 15, 1850, xii; from July 1, 1849, to Oct. 31, 1849, 98; from Nov. 1, 1849, to Dec. 31, 1849, 205; from Jan. 1, 1850, to March 31, 1850, 344; from April 1, 1850, to June 30, 1850, 479. Echinidz, Portuguese fossil, description of, 195. Echinopsis? subuculus, 196. Echinus Olisiponensis, 195. Effects of expansion and contraction on the strata of the Alps, noticed, 1. Egerton, Sir P. G., on the Ganoidei He- terocerci, 1. English Channel, age of the valley of the, 87. , Mr. R. A.C. Austen on the valley of the, 69. , distribution of materials in the valley of the, 76. Eocene iron ore, Mr. A. Tylor on, 133. Equisetum Brodiei, 414. Erratics of the Alps, noticed, Ixii. Erzeroom, notice of the occurrence of coal near, 367. Eschara polo, Etna, noticed by Sir C. Lyell, 227. Eurynotus, Sir P. G. Egerton on the genus, 2. Exogyra Olisiponensis, 185. plicata, 184. Extent of the post-eocene seas, noticed, XXXIX. Ezquerra del Bayo, Don J., on the geo- logy of Spain, 406. Farringdon, Mr. R. A. C. Austen on the fossiliferous sands and gravels of, 455. Fasciolaria intermedia, 49. —— semistriata, 49. Fletcher, Mr. T. W., on the Dudley Tri- lobites, Part I. 235; Part IT. 402. Flysch, Sir R. I. Murchison on the, noticed, xxxvii. Folded strata of the Alps, noticed, xli. Forbes, Prof. E., on the fossiliferous de- posits in the Middle Island of New Zealand, 343. Formation of granitic and mineral veins in modern times, noticed, Ix. Fusus Haitensis, 49. Henikeri, 49, Gabbro rosso, noticed by Sir R. I. Mur- chison, 374. Ganoidei Heterocerci, Sir P. G. Egerton on the, 1. Gervillia Fittoni, 186. —— Sobralensis, 186. Glacial theory, noticed, lxv. Glaciers and icebergs, noticed, Ixii. Glarus slates and Monie Bolca lime- stone, noticed, xxxvil. Gradual subsidence of sea-bottems, no: ticed, liii. Granite, crystallization of, noticed, li; formation of modern veins of, no- ticed, Ix. Granitic rocks of the Alps, noticed, xl; age of, noticed, lix. Graptolites convolutus, 64. Griestoniensis, 63. laxus, 64. Ludensis, 64. Great length of time required for denu- dation and oscillation of lands, lv. Greensand, at Devizes, noticed by Mr. R. A. C. Austen, 468. , lower, at Seend, noticed by Mr. W. Cunnington, 453. Gypsum and dolomite of the Alps, no- ticed, xlix. Gyrolepis, Sir P, G. Egerton on the ge- nus, 8. Hamilton, Mr. W. J., on the occurrence of a freshwater marl in the fens of Cambridgeshire, 451. Harkness, Mr. R., on the new red sand- stone of the southern part of the Vale of the Nith, 389. Hippurite limestone of Portugal, Mr. D. Sharpe on the, 139. Hippurites ? ——, 415. Hopkins, Mr. E., on the crystalline rocks of the Andes and their cleavage planes, 365. Hopkins, Mr. W., award of the Wol- laston medal to, xxiii; reply on receiving it, xxv; on the elevation and denudation of the Lake district, Ixili. Horner, Mr. L., on sculptured marks on rocks in the Nile valley, 384. Icebergs and glaciers, noticed, I xii. Improbability of the occurrence of cata- clysmal waves, noticed, Ixiv. Inferior oolite, Rev. P. B. Brodie on cere tain beds of the, 239. Iron ore, eocene, noticed by Mr. A. Ty- lor, 133. INDEX TO THE PROCEEDINGS. Ischypterus, Sir P. G. Egerton on the genus, 8. Italy, Sir R. I. Murchison on the earlier volcanic rocks of, 281. Jurassic series of Portugal, noticed by Mr. D. Sharpe, 156. Lake district, Mr. W. Hopkins on, no- ticed, Ixiil. Lammermuirs, old red conglomerate of the eastern, 419. Lamna ——, 329. Lardarello, Soffioni at, noticed by Sir R. I. Murehison, 370. Leckhampton Hill, section of, 239. Lepadide, British fossil, Mr. C. Darwin on the, 4389. Lias, fossil plants from the lower, 413. Lichas Barrandii, 238. —— Bucklandi, 235. Grayii, 237. —— hirsutus, 236. —— Salteri, 237. London clay, basement bed of the, 255. Lower greensand, section of, at Seend, 453. Lycett, Mr. J., and Mr. J. Morris, on Pachyrisma, 399. Lyell, Sir C. (President), Address on awarding the Wollaston medal to Mr. W. Hopkins, xxiii; Address on- awarding the Donation Fund to Mr. J. Morris, xxvi; Anniversary address, February 1849, xxvii. Notices of de- ceased Fellows: Christian VIII., king of Denmark, xxvii; the Earl of Auck- land, xxviii; Mr. William Clift, xxix; Mr. Frederick Dixon, xxxi. Sir R.I. Murchison on the structure of the Alps, Apennines and Carpathians, xxxiv; M. Boué on the nummulitic rocks, xxxv; Al. Brongniart on the eocene shells of the Diablerets, xxxv; the Biaritz shells, xxxv; the nummu- litic beds, xxxvi—xxxix; the Glarus slates and Monte Bolca limestone, xxxvil; Mr. Prestwich on the English tertiaries, xxxvii; Sir R. I. Murchi- son on the Flysch, xxxvii; the date of the upheaval of the Alps, xxxviii; the extent of the post-eocene seas, xxxix; the granitic rocks of the Alps, xl; the folded strata of the Alps, xli; the paroxysmal hypothesis, xliii; M. d’Archiac’s ‘ History of the Pro- gress of Geology,’ xliii; M. d’Archiac on active volcanos, xliii; comparison of disturbing causes in ancient and modern times, xliv; changes in the organic and the inorganic worlds, xlv; continuance of existing faune during alterations of level in the Mississippi valley and in Scandinavia, xlvii; the volcanic rocks of the Alps and Pyre- nees, xlviii; the relation between the axis of the Alps and the strike of the strata, xlix; the dolomites and gyp- sum of the Alps, xlix ; the effects of ex- pansion and contraction on the strata of the Alps, |; the crystallization of granite, li; the nagelflue and its ori- gin, li; the gradual subsidence of sea- bottoms, lili; the great length of time required for denudation and oscilla- tion of lands, lv; the dislocations and lateral movements of the Alps, lvii; the age of the granitic rocks of the Alps, lix; the formation of granite and mineral veins in modern times, lx; the erratics of the Alps, lxii; gla- ciers and icebergs, lxii; Mr. Hopkins on the elevation and denudation of the Lake district, lxili; the improba- bility of the occurrence of cataclysmal waves, lxiv; the glacial theory, lxv; comparison of the climate of the car- boniferous epoch with that of the present age, lxv. Lyell, Sir C., on craters of denudation, and on the structure and growth of volcanic cones, 207. Mammalian remains at Brentford, Mr. J. Morris on the occurrence of, 201. - Manon , 000. Mantell, Dr. G. A., on the remains of Dinornis and other birds, and on fossils and rock-specimens from the Middle Island of New Zealand, 319. , on the Northern Island of New Zealand, 319. , Mr. R. N., on the oolite of Wilts, 310. Marginella coniformis, 45. Marginopora 4 ol. Marl, in Cambridgeshire, Mr. W. J. Ha- milton on a bed of freshwater, 451. Mastodon angustidens, discovery of a skeleton of, near Asti in Piedmont, 252. Metamorphic rocks of Nova Scotia, 347. Mexico, voleanic rocks of Northern, 251. Mitra Henikeri, 46. varicosa, 46. Monte Bolca limestone and Glarus slates, noticed, Xxxvii. Monte Nuovo, noticed by Sir C. Lyell, 225. Monts Dor and Cantal, noticed by Sir C. Lyell, 234. Moore, Mr. J. C., on some tertiary beds in the island of San Domingo, 39. ——, on sliells in the Till, 388. Morris, Mr. J., and Mr. J. Lycett, on INDEX TO THE Pachyrisma, a fossil genus of lamelli- branchiate mollusca, 399. Morris, Mr. J., award of Donation Fund to, xxvi; reply on receiving it, xxvi. ; on the occurrence of mammalian remains at Brentford, 201. , on Zamites gramineus, 199. Mount Loa, noticed by Sir C. Lyell, 232. Murchison, Sir R. [., on the structure of the Alps, Carpathians and Apen- nines, noticed, xxxiv; on the Flysch, noticed, xxxvii; on the detritus of the Alps, 66; on the earlier volcanic rocks of the Papal States and the adjacent parts of Italy, 281; on the vents of hot vapour in Tuscany, and their re- lations to ancient lines of fracture and eruption, 367. Murex Domingensis, 49. Mytilus Beirensis, 187. —— Morrisii, 187. Nagelflue, and its origin, noticed, li. Naiadacee, Prof. J. Buckman on the, 415. Naiadita lanceolata, 415. obtusa, 415. —— petiolatu, 415. Nash Scar limestone, Mr. J. E. Davis on the, 432. Natica subclausa, 51. Lusitanica, 192. Nerinza, Mr. D. Sharpe on the genus, 101. Nerineu annulata, 112. —— Archimedis, 103. —— Bruntrutana, 104. Conimbrica, 114. Dupiniana, 103. Eschwegii, 113. —— grandis, 104. ——,, list of species of, 105. nobilis, 111. —— Olisiponensis, 114. —— Titan, 112. turbinata, 113. Nerinella, list of species of, 105. ——, Mr. D. Sharpe on the subgenus, 103. . Nerita turbinata, 192. Neritina bicornis, 192. New red sandstone of Dumfriesshire, Mr. R. Harkness on the, 389. New Zealand, Dr. G. A. Mantell on the geology of the Middle and Northern Islands of, 319. ——, Prof. E. Forbes on the fossiliferous deposits in the Middle Island of, 348. Nicol, Mr. James, on the Silurian strata of the south-east of Scotland, 53. Nile-Valley, Mr. L. Horner on sculp- tured marks in the, 384. PROCEEDINGS. Nith, Mr. R. Harkness on the new red sandstone of the Vale of the, 389. Notices of deceased Fellows, xxvii— XK. Nova Scotia, the metamorphic and me- talliferous rocks of Eastern, 347. Nucula (Leda) Phillipsii, 318. Nummulina, Dr. Carpenter on the struc- ture of, 21. Nummulina complanata, 25. —— levigata, 22. Nummulitic rocks, noticed, xxxviii. , Dr. Boué on the, noticed, xxxv. Old red conglomerate of the Eastern Lammermuirs, Mr. W. Stevenson on the, 418. Oliva cylindrica, 45. Onekakara, pleistocene clay of, 3380. Oniscia Domingensis, 47. Oolite of Leckhampton Hill, Rev. P. B. Brodie on the inferior, 239. of Wilts, Mr. R. N. Mantell on the, 310. Orbitoides, Dr. Carpenter on the struc- ture of, 32. Orbitoides Mantellii, 32. —— Prattii, 33. ° Orbitolites, Dr. Carpenter on the struc- ture of, 30. Orbitolites complanata, 31. Ostrea Haitensis, 53. Ototara limestone, 328. Pachyrisma, Messrs. Morris and Lycett on the genus, 399. Pachyrisma grande, 401. Palzoniscus, Sir P. G. Egerton on the genus, 4. Pal@oniscus arcuatus, 7. Beaumonti, 6. catopterus, 4. decorus, 7. Egertoni, 5. Gelberti, 5. macrophthalmus, 6. megacephalus, 6. Monensis, 5. ornatus, 4. —— pygmeus, 6. speciosus, 4. Tchefkini, 5. Palichthyologic notes, No. 3, by Sir P. G. Egerton, 1. Palma, island of, noticed by Sir C. Lyell, 213. Paroxysmal hypothesis, noticed, xlv. Pecten inzqualis, 52. (Janira) inconstans, 188. —— Lusitanicus, 189. oxygonus, 52. Thetidis, 52. Pectunculus acuticostatus, 53. INDEX TO THE PROCEEDINGS. Perna? fragilis, 189. Lusitanica, 189. polita, 190. Petaloconchus Domingensis, 51. Pinnularia » do2. Plectrolepis, Sir P. G. Egerton on the genus, 3. Pleurotoma consors, 50. Haitense, 50. Henikeri, 50. Jaquense, 51. venustum, 50. Polycystina , 332. Portugal, list of organic remains found in the secondary strata of, 170. , Mr. D. Sharpe on the hippurite limestone of, 139. ; , on the Jurassic series of, 156. —, , on the secondary rocks of, 135. : , on the species of Nerinza found in, 101. ; , on the subcretaceous series of, 141. Post-eocene seas, extent of, noticed, *XXXIX. Prestwich, Mr. J., on the English ter- tiaries, noticed, liv. , on the structure of the strata be- tween the London clay and the chalk, 252, Ptygmatis, list of species of, 108. ——, Mr. D. Sharpe on the subgenus, 104. Pustulopora Zealandica, 331. Pyramidella? sagittata, 193. Pyrenees, volcanic rocks of the, noticed, xlvili. Pyrula consors, 49. Pyzxidicula » 002. Relation between the strike of the strata and the axis of the Alps, noticed, xlix. Report, Annual, i. of the Library Committee, ix. of the Museum Committee, ili. Rocea Monfina, noticed by Sir R. I. Murchison, 300. Rostellaria Coste, 193. Ruxton, Lieut. G. F., on the volcanic rocks of Northern Mexico, 251. St. Paul, island of, noticed by Sir C. Lyell, 221. Santorin, noticed by Sir C. Lyell, 215. Scotland, Mr. J. Nicol on the Silurian rocks of the south-east of, 53. Secondary rocks of Portugal, 135. Sharpe, Mr. D., on the genus Nerinza, 101. , on the secondary district of Por- tugal, north of the Tagus, 135. Sigillaria, and some accompanying spores, noticed by Mr. E. W. Binney, ive Silurian rocks of south-eastern Scot- land, 53. Sismonda, Prof. E., on the discovery of a skeleton of Mastodon angustidens near Asti, in Piedmont, 252. Smith, Mr. J. (of Jordan Hill), on the occurrence of marine shells in strata below the Till, 386. , on the shells of the Till near Wick, 386. Soffioni of Tuscany, noticed by Sir R. I. Murchison, 367. Solarium quadriseriatum, 51. Spain, the geology of, 406. Spirifer Beirensis, 191. Spondylus bifrons, 53. Stauroneis Zealandica, 332. Stevenson, Mr. W., on a gap in the grey- wacke formation of the Eastern Lam- mermuirs filled by old red conglome- rate, 419. Stowe, Mr. W., on a cutting in the rail- way near Buckingham, 135. Strickland, Mr. H. E., on a section of Leckhampton Hill, 239. Strombus ambiguus, 48. bifrons, 48. Haitensis, 48. proximus, 48. : Subcretaceous series of Portugal, 141. Subsidence of sea-bottoms, noticed, liii. Surrirclla » 002. Swindon, oolitic beds at, noticed by Mr. R. A. C. Austen, 464. Sydney coal-field, Mr. R. Brown on the lower coal-measures of the, 115. Taranaki, infusorial earth of, 332. Tellina Sobralensis, 190. Terebra bipartita, 47. inequalis, 47. obconica, 194, sulcifera, 47. Terebratula Beirensis, 192. Gualteri, 329. Tertiaries of the Moray Firth and the great Caledonian valley, the Rev. J. G. Cumming on the, 10. Tertiary strata in the island of San Do- mingo, Mr. J. C. Moore on some, 39. Tertiary strata, Mr. J. Prestwich on the lower, 252. Tertiary strata and their dislocations in the neighbourhood of Blackheath, the Rev. H. M. De la Condamine on the, 441. Textularia » 330. aciculata, 330. elongata, 330. INDEX.TO THE Till, Mr. J. C. Moore on shells in the, 388. , near Airdrie, Mr. J. Smith (of Jordan Hill) on shells in the, 386. ——, of Caithness, Mr. J. Cleghorn on the, 385. Toxaster Couloni?, 197. Travertine, Sir R. I. Murchison on, 287. Trigonia Lusitanica, 190. Trilobites, Mr. T. W. Fletcher on Dud- ley, Part I. 285; Part II. 402. Triton simillimus, 48. Trochalia, list of species of, 107. , Mr. D. Sharpe on the subgenus, 103. Trowbridge, oolite and fossils at, noticed by Mr. R. N. Mantell, 310. Turbinellus Haitensis, 50. validus, 50. Tur binolia , ool, Turbo Munda, 194. Turrilites Beirensis, 194. Turritella Cintrana, 194. rosea, 301. Tuscany, vents of hot vapour (Soffioni) iM obit. Tylor, Mr. A., on productive iron ore in the eocene formation of Hamp- shire, 133. Typhis alatus, 48. Upheaval of Alps, date of, noticed, xli. PROCEEDINGS. Valley of the English Channel, Mr. R. A. C. Austen on the, 69. Venetian Alps, M. de Zigno on the stratified formations of the, 422. Vents of hot vapour (Soffioni) in Tus- cany, 367. Volcanic cones, Sir C. Lyell on the structure and growth of, 207. Volcanic rocks of Italy, Sir R. I. Mur- chison on the earlier, 281. —— of Northern Mexico, Lieut, G. F. Ruxton on the, 251. Voluta pulchella, 46. soror, 46. Waihora, infusorial earth from the lake, 333. Waikonaiti, remains of birds at, 334. Wanganui, pleistocene clay of, 332. Weston, Mr. C. H., on the diluvia and valleys in the vicinity of Bath, 449. Wiits, oolite of, noticed by Mr. R. N. Mantell, 310. Wollaston Donation Fund, award of, ORV Wollaston medal, award of, xxiii. Wood, Mr. S. V., on the age of the upper tertiaries in England, 201. Zamites gramineus, 199. Zigno, M. Achille de, on the stratified formations of the Venetian Alps, 422. END OF VOL, VI. PRINTED BY RICHARD AND JOHN E. TAYLOR, RED LION COURT, FLEET STREET, A . A as . : a 5 s y “ if i 3 wea wete” “hoe? ey - - z ; : i. - . ¥ Fi 2 eS b 7 5 ; ‘ Ls - } ¥ T of . a -—— » . $ ” F ¢ F z ¥ = NV s la =) i Eaer- = : ? *, =— : A ae) : ( yf - hed ~ ~ XL im my = ‘ ce é s m 3 7 ms ze {ADA ET 3 42a ee ee ae efi a is 7 Te ce : THFTt, Fee ror ger 4 —~ _ 3 i A > j Si Sl * - ~ bn Pi e ee Nah sane SSTeTETEIETILH HH { : : : i eae i + = prs eee * 1 MMH i 3.9088 01350 1507