A hy aed ‘ tl A ¥ Or ee i a 2 : Cae ea bel Re De ' eS BR den ae dake . , eae 2 vB rod ‘ . Wow stk . ; ‘ ee raaveee > , . pawn ay rit Yo IIR tetas Ts is vag eh A ' ‘ + PAR CLA LT A Ye tas Wi A ) 5 , Ae " Sa ta pe ARN : WY 43 oh Min ae Aarne * , \ cae ‘ ‘ ; ‘ BAN eS SU aM s t i ws ok id TAR ! uth ' Pye mA einen tS Ve. AY fr ay 4 ae ‘ Oy ee Rae: heey . t,) 4 t ia » arr ‘ 5 i yoy ve ‘ c $ . * * we 3 ” ea Ieeavavile ® ‘ . E AAs 1 " . , oe eet oo ‘ : 7 Tit PE Jn . 4 brain he ve 3 .’ a0) ' > * > . \ + . ’ 4 4 ALY bP ace : P aot HALTS z Wee x ’ wR & A ee Se se ht j i 3. f . * } f P ‘ de a hee ot 4 i oF are ag * ¥ « dA Rw Se Std fF ” bees Pret Ve ELS wort Oe tk a ma iy ow ee ae 7 aye A, Pr eee en ee ee , s> t ; A : ‘ +n +2 ; ea te * a5 : Pha apg Mn alhail al agt ig yr Peal ke . TAP Lyla ad ala eg Wak sed tae pei ke ay Pt Putas i! tS A MES ode ee oe t . " fe oe eas y Pgh Le ALS Veh wie ee utes ‘ y b + re #3 7 " Pe ee te ae: es oad ee een Paina y sted Me TS) ewe Ms fy Ce Sd Ate BoP aoe i ahd a oenthe: “Sail kW a Senko? eb laet ene aan { PR pith tine eS + ‘ %, s f k + vf oh ee oe WW om Pgh ‘ ot ER ty & yh es aerate ig NOGA aight atl NS acta ta ERE AOS RE ERNE ot wi ba tr ‘ Rit] rt . Poy o 4 16 6 Wa (ry 7 ry Lie te aig AB oe a anys PSY A ve isv Dd 0 OFF Oe ode Moe 7 ae Eien? Bsns ‘ , ee LA 17 ee ew ED ee a Se tes Poa ra ie dye bo biel ed» Ep icc 2 9, A ash ah Ae Pope bats iy At $i aye eee i heb & 8D. iLOLOGY. 5 GE Digitized by the Internet Archive in 2010 with funding from University of Illinois Urbana-Champaign http://www.archive.org/details/panamericangeolo21888desm THE AMERICAN GEOLOGIST A MONTHLY JOURNAL OF GEOLOGY AND ALLIED SCIENCES. EDITORS AND PROPRIETORS. PROF. SAMUEL CaLvIN, University of Iowa, Iowa City, Iowa. PrRoFr. EDWARD*-W..CLAYPOLE, Buchtel College, Akron, O. Dr. PERSIFOR FRAZER, Franklin Institute, Philadelphia, Penn. Dr. Lewis E. Hicks, University of Nelraska, Lincoln, Neb. Mr. EDWARD O. Uxricu, Geol. Survey of Illinois, Newport, Ky. DR. ALEXANDER WINCHELL, University of Michigan, Ann Arbor, Mich. Pror. NEwton H. WINCHELL, University of Minnesota, Minneapolis, Minn. VOLUME II JuLy To DEcemBeErR, 1888 MINNEAPOLIS, MINN. 1888 PRINTED BY L. KIMBALL & CO. aU he CONTENTS. JULY NUMBER. On Psammichnites and the early trilobites of the Cam- brian rocks in eastern Canada. G. F. Matruew... 1 Palzontologic and stratigraphic “principles” of the ad- versaries of the Taconic. JULES MARCcOU......... 10 On some fossils from the lower coal measures at Des Moines,-fowa.. CHarnes BR.’ Kryns...........0. 23 On some investigations regarding the condition of the anterior of the earth: Hi. W.,CLAYPOLE.....'...°.. 28 The post-glacial geology of Ann Arbor, Mich. C. W. °C SUN SEES 5) Boga pe Ae AI Oe. ie a 35 A correlation of the lower Silurian horizons of Tennessee, and of the Ohio and Mississippi valleys with those of New York and Canada. EH. O. ULrion......... 39 Geology as a means of culture. ALEXANDER WINCHELL. A4 Editorial Comment.—The antiquity of man; some incidental results of the discussion, 51. Review of Recent Literature, 54.—Considerations sur les fossiles decrits comme Algues. G. MATLLARD, 54.—Synopsis of the flora of the Lar- amie group. Warp, 56.—(n an Archean plant from the white crystal- line limestone of Sussex county, N. J. Brrrron, 58.—Geological survey of Ohio, vol. vi; Economic genlogy. ORTON,58._ . Correspondence.—The Huronian of Canada. A. R. C. Senwyn, 61.—Lake beaches at Ann Arbor. F. W. SpeNcER, 62.—Dr. Clark’s collection of fish remains at Berea, O. E. W. CLAYPoLe, 62.—Geyserite vs. vol- canic dust, in Nebraska. L. E. Hicxs, 64.—The so-called marine beaches of Long Island. Joun Bryson, 65. Personal and Scientific News, 65.—Minnesota Academy of Natural Sciences. —Geological map of Europe.—Publications of the International Geo- logical Congress.—The late professors Wright, Worthen and Irving. —The appointments of Drs. Wadsworth and Lindahl. AUGUST NUMBER. Paleontologic and Stratigraphic “ principles ” of the ad- versaries of the Taconic. [u.] JuLes Marcov... 67 Some remarks on the present state of our knowledge of the North American eastern Tertiary. Orro Mryer, Pye Tae Ree ee Sich Se cals cise diesels dig sual siege 88 Geology of the Montmorenci. [ From the American Mag- azine, 1847.] HpBeNnrzeR Emmons, M. D.......... 94 Geology as a means of culture. [u.] ALEXANDER WIN- BUEN a sais oe Seer se iaie es wie arate vee ie a choi ache aes) ews 100 Prof. Amos H. Worthen. *E. O. Utricn. [Portrait.].. 114 - iv Contents. Editorial Comment.—The Parliament of science in the United States, 117. Review of Recent Literature.— History and character of Septastrea, and its identity with Glyphastrea— Spicules of Archéeocyathus minganensis —Chert and schists of Spitzbergen, and sponges described by Dr. E. von Danikowski, G. J. HinpkE, 127-128.— American geological clas- sification and nomenclature, JuLES Marcou, 129.— Three formations of the Atlantic slope, W. J. McGer, 129.— The Syncarida, A. 8S. Pack. ARD, 131.—- Wind-blast accompanying avalanches, J. A Symonps, 132. — New trilobite in the slate quarries of Wales, Dr. H. Woopwarp, 182.— Relations of fossil fish to one another, Dr. TRaQuarR, 133,— Geol. and Nat. Hist. Survey of Canida[vol. 1], 133. Correspondence.— The Taconic at Quebec, A. R. C. Senwyn, 134.— Earth- quake tremors at Charleston, CLAYPOLE, 135.— @lacial origin of the beaches of Long Island, Bryson, 186.— The Taconic at Boston, HyArv, 137. Personal and Scientific News.— Messrs. Claypole, Nutting and McGee.— Cleveland meeting of A. A. A.S.— Drs. Frazer and T. Sterry Hunt sail for Europe.—The appointment of R. T. Hill.— W. T. Cummins on Texas Carboniferous, 137. + SEPTEMBER NUMBER. The International Congress of Geologists. Reports of the American. Committee... 2.0.2 es: PUMP mien 139 Report of the Sub-Committee on the Archean. By Prr- BEROR NERA ER oes cheers oW hs a ecu Lae Rs 143 A, Opinions on the work of previous sessions of the Congress, 146.—. Propositions for the division of the Ar- cheean, 153.—C. Horizons of unconformity in the Archean, 157.—D. Petrographical and chronological sub-divisions of the Archean, 159.—#. How should the eruptives be classi- fied? 160.—#. Hebridian, Dimetian and Arvonian, 163—G. Crystalline rocks later than the Archean, 164.—H. Crystal- line rocks in the Archeean that occur later, 167.—7. Is min- eral constitution indicative of age? 168.—/. Is the Archzean of igneous or sedimentary origin? 171.—H. What evidences of life inthe Archean? 173—LZ. Is Hozoon canadense of or- ganic origin? 175.—ZL. System of coloring eruptives on -maps, 176.—M. Should serpentine constitute a class of eruptives? 179.—N. Is serpentine an alteration product of sedimentaries or of eruptives? 180.—Conclusions, 181.— Appendix I. Ciaims of the term Azoic, 184—Appendizx IT. Opinions of some English géologists on the Archean rocks, 187. Report of the Sub-Committee on the Lower Paleozoic. By iN Wie Wah CPB 3.22.5 ie ai. Salis Ms eaten 193 Introductory, 193.—General Principles, 196 —Views of Prof. J. D. Dana, 198.—Recommendation of Mr. 8. W. Ford, 199.—Communications from Profs. Hall and Hitchcock,200.— Views of Dr. T. Sterry Hunt, 202.—Researches of Prof. Jules Marcou, 202.—Views of Dr. Alexander Winchell, 202.— Communication from Dr. J. S. Newberry, 203.-—Other opinions, 207.—Discussion of evidence and opinion, 208.— Use of the term Taconic, 208.—Use of the term St. Croix, 209.—Use of the terms Menevian and Ordovician, 211.— Resume, 211.—Conclusions, 212.—Synopsis of the opinions of Mr. Walcott, 215—219.—Note by. the reporter on Mr. Walcott’s views, 220—22+. Contents. CTOBER NUMBER. Report of the Sub-Committee on the Upper Paleozoic (Devonic). By Henry 8. WILLIAMS ...... ..... The name proposed by Sedgwick and Murchison in 1859, 225.—The term Erian, proposed by Sir Wm. Dawson in 1871, 227.—The Devonian areas of North America, 228.— Conclusions from the study of these areas, 235.—The base of the Devonian, 237.—The top of the Devonian, 239.—Three distinct marine faunas in the Upper Paleozoic, 240 —Sub- divisions not recognizable by sharp lines, 242.—Problems for settlement, 245. Report of the Sub-Committee on the Upper Paleozoic (Carbonic.) By J. J. STEVENSON...... isthe hohe The general grouping of the Carbonic, 248.—The Upper Carbonic—The upper coal measures, 249.—The middle coal measures, 250.—The lower coal measures, 251.—The Lower Carbonic—The Greenbrier, 252—The Poceno, 253.—The region beyond the Rocky mountains, 254.—General table, 256. Report of the Sub-Committee on Mesozoic. By GEorGE Uo) LEONE OE Ste a ee The Triassic, 257.—The Cretacic, 259.—The Mesozoic Realm, 261.—The post-Cretacic system, 265.—Note on the Mesozoic systems, 267. G Report of the Sub-Committee on the Cenozoic (Marine) SEG UNH, Ae OMIT ED © 35 crew's Oxce siv'oln sie ae Acie a a 6"e Eocene of Alabama and its sub-divisions, 270.—Grand Gulf Series of Mississipni, 273.—Summary descriptions of the parts of the Eccene, 275.— Oligocene, 276.—Miocene, 277. —lLater Tertiary. Note, embracing letters from Profs. Heil- prin, Hileard, Newberry, Whitfield, Dall, Wincheil and Le- Conte, 278. Report of the Sub-Committee on the Cenozoic (Interior) Pee PU OP EAN ie oa )ej5 (al opace bi ols mip dees bite araile-« Description and characteristics of the Cenozoic, 285.— Eocene system and its divisions, 287.—Miocene system and its divisions, 290.—Pliocene system and its divisions, 292. —Plistocene system and its divisions, 294.—Note on the Cenozoic series, 298. Report of the Sub-Committee on the Quaternary and PEGE GS yyw. be ELIVOHCGCK 12). Gadel 6 s\s\aieeisits, 5 Definition of Quaternary and general views, 300.—The Ailantic coast, 300.—Lower Mississippi valley, 304.—Quater- nary of the Interior, 804.—Table of epochs, sub-epochs and attendant phenomena, 305. NOVEMBER «NUMBER. Sketch of the Life and Character of Charles KE. Wright, late State Geologist of Michigan (Portrait.) C. mation of Pennsylvania [ Illustrated.] Henry A. RMA MUPUI ENS tick, Seute) oe preys od inp wig te takes’ 64 Fritters The original Chazy rocks [Map]. Pres. Ezra BrarNerp and Prof. H. M. SEELY EL Ltae hace Mae ee eis ROTM 225 248 207 269 a CO oN 300 dll 323 v1 Contents. Pockets containing fire-clay and carbonaceous materials in the Niagara limestone at Clinton, Iowa, Padi HinNewonwi hs (ory eee ene culh oes ee Editorial Comment.—¥ormation of coal seams, 384. Review of Recent Literature, 336.—Die carbone Eiszeit. Dr. W. WAAGEN, 336.—Tables for the de termina tion of common minerals. W. 0. Crossy, 3840.—Geology; Chemical, Physical and Stratigraphical. JosEPH PRESTWICH, 341. —Decomposition of iron pyrites. A. A. JULIEN, 3844.—Five papers on the orig n and ancient drainage of the basins of the great lakes. J. W. SpeNcER, 346.—Les disloca- tions de l’ecorce terrestre. MM. MArGEerin BT Her, 348. Recent Publications.—349. Correspondence, 351.—A green quartzyte from Nebraska. L. E. Hicks, 30l.—Some forgotten Taconic literature. A. W. Voapns, 352. —Geology of the vicinity of Quebec City. JutEs Marcou, 355.— The position of the Olenellus beds. A. G. Naraorst, 356.—Dr. Rom- inzer’s rejoinder to Mr. C. D. Walcott, 356. Personal and Scientific News—The Am. Asse. Adv. Sci., 359--The Am. Geol. Soc., 860.—Roy. Soc. of Can., 361—The International Congress of Geologists, 363—Univ. of Georgia, 370.—Univ. of Texas, 370.— Etc. etc., DECEMBER NUMBER. Prof. Henry Carvill Lewis and his work in glacial geol- ogy. [| Portrait.] Warren Upnam........ 371 The ethical functions of scientific study. Prus. TC. COAMBERGIN. (22 nar. Mes peeryecine oe Sete sneer 380 The Coal Measures of central Iowa, and particularly i in the vicinity of Des Moines. . [Tilustrated ) CHAR Es BOWES ieee) AR Sails cher el Perec ely ie capone aa 396 Preliminary description of a new or little known saurian frcm the Benton of Kansas. F. W.Craain....... 404 Keokuk group at Crawfordsville, Indiana. CHARLES S. IDMAGHLER 10. seeds sir eh ei aie ieee Gaye ea oa 407 Notes on a geological section at Todd’s fork, Ohio. [ I- Tustrated.!|oAnciab HORSE \cy).y.7.) vail alee aetenge 412 ag Commenit.—The Fifty-eighth meeting of the British Association, Review of Recent Geological Literature, 428.—Formal recoguition of the trans- fer of the Lick Observatory to the Regents of the University of Cali- fornia, 428.—The beginnings of American science, G. BROWN GOODE, 429.—The coals of Colorado, J. 8S. Newnurry, 429.—Glaciation; its relation to the Lackawanna-Wyoming region, Joun C. BRANNER, 430. —The Jordan, Arabah and thé Dead sea, Isrann C. RussELL, 430.— Microscopical physiography of the rock-forming minerals, J.‘ H. Rosensuscu, 430.—Anti-Evolution: Girardeau vs. Woodrow. JAMES G. Martin, 431.—Congres geologique International, Compte rendu de la 3mo Session, 431.—On the fauna of the lower Coal Measures of central Iowa, and descriptions of two new fossils from the Devonian of Iowa, Cuas. R. Keyes, 432.—Glacier erosion in Norway, J. W. SPENCER, 482. Correspondence, 433.—Mitchell county, Texas, G. C. BroADHEAD, 483.— The Literature of geyserite, Geo. P. Merritt and L. E. Hicks, 437, Personal and Scientific News, 438. Index, 489. AMERICAN GEOLOGIST Vo. II. JULY, 1888. No. 1. ON PSAMMICHNITES AND THE EARLY TRILOBITES OF THE CAMBRIAN ROCKS IN EASTERN CANADA. BY G. F. MATTHEW. In this part of the continent there are several series’ of rocks which may properly be referred to the Cambrian system. The following article refers to two of these and describes some of the most noticeable features of their faunas. A. Etchiminian Sertes. This the oldest of these series is not known to have any trilo- bites; nor have animals of this order been found in the rocks which in Wales and Norway are supposed to be of equivalent age. Throughout its whole thickness organic remains are scanty, or are so small, or obscure, as not to be readily observed. In traversing the outcrops of its measures one is at times arrested by the abundance of worm burrows, casts and tracks, indicating the existence of abundant life of a certain kind. These tracks and casts are found in the very oldest beds which are capable of preserving the imprint of organic remains; they occur in sandstones and shales immediately above the conglom- erate at the base of the series. This conglomerate, about 60 feet thick, rests upon amygdaloidal greenstones, which in the report of the geological survey of Canada are referred to the Huronian system. About two hundred feet higher in the series there are fine 1 By this term the writer designates the grand divisions of a geolog- ical system marked by a distinctive fauna and usually separated from the series above and below by unconformities. Thus there are in this region 3 series of Cambrian rocks, 2 of Ordovician, 1 of Silurian, 2 of De- vonian, 3 of Carboniferous. 2 Early Trilobites of the Cambrian Rocks—Matthew. e branching organisms resembling seaweed and about one hun- dred feet higher a remarkable track occurs which is also found in the oldest Cambrian rocks of Sweden. This was named by Dr. Otto Torell Avenicolites gigas, which name he afterward changed to Psammichnites gigas. Although he at first thought this track to have been made by a worm he afterward demurred to the absolute reference of such trails to the An- nelida, remarking that both molluscs and crustaceans made similar marks on the sand. But no gasteropods except minute species are known in these ancient rocks, and there is such a variety of trilobites both for size and form in the Acadian series to which Psammichnites extends that the trilobita do not seem likely to have given origin to a track so unchanging in size and with such features as this possesses. Psammichnites is most probably the track of a gigantic ma- rine worm. The centre is moderately depressed and there is the same tendency to make little ridges on each side of the track when passing over the raised part of ripple-marked sandstones and to throw casts (of the intestinal canal?) in the hollows or depressions between the ridges, which may be observed to characterize the operations of worms on the sea shore at the present day. The track however, differs from ordinary worm trails in its directness, running almost straight for many inches and sometimes for the distance of a foot, and deviating from the straight line only in long open curves. As it lacks the sinuous- ness of the ordinary worm track, the animal that made it may have had perceptive organs to guide it on its course, differing from those of ordinary worms, The track is about three-quarters of an inch wide and is often marked by a groove or depression in the middle, as in Cruziana, Apparently the same track is found in the Acadian series near its base where the casts that accompany it occasionally contain shells of brachiopods ( Léxzarsonia) pteropods ( Diplotheca) and tests of trilobites (Agvaulos, &c.). Whether these are acci- dental enclosures, or have passed through the intestinal canal is not clear, but the latter view seems more probable. This fossil track serves to link the two series and shows with other biologi- cal features that the lower, as well as the upper series, is of Cambrian age. ¢ Early Triobites of the Cambrian Rocks—Maithew. 3 The lower series also contains worm tracks of ordinary size ( Helminthites) and the double worm burrows named by J. W. Salter Arenicolites. It has also yielded an example of a large thin-shelled brachiopod similar to Lingwla (2) monolifera of the Eophyton sandstone of Sweden. This series of Cambrian rocks is about 1200 feet thick. B. Acadian series. The series above described is overlaid unconformably by the Acadian or St. John series which has an abundant trilobite fauna in its lower part—Stage (or Division) 1. All the genera of trilobites of this stage are known in the Cambrian system in Europe, and are the following: Paradoxides, Ellipsocephalus, Solenopleura, Ptychoparia, Liostracus, Agraulos, Ctenocephalus, Conocoryphe, Microdiscus and Agnostus. Trilobites in the comparative rapidity with which they were introduced in the several layers of the palwozoic strata, and the short period during which the species remained in existence, serve the same purpose in discriminating the members of the ancient geological systems, as in the Tertiary strata is fulfilled by the mammals. This peculiarity of these ancient crustaceans is well shown in the close parallelism of the species on both sides of the Atlantic, and the rapid exchange of one species for another in passing from older to younger beds of the Cambrian system. In the lower part of this system (e. ¢. stage 1) we do not find many identical species in Scandinavia and Acadia; but there are a large number of representative species; these do not. occur in exactly the same order in the two countries, for some forms that show themselves first in Europe, as Paradoxi- des tessini, appear later here (7. abenacus); and others that are found among the oldest here P. eteminicus (cf. P. rugu- Zosus) make their appearance as constituents of a later sub-fauna in Europe. There are some sub-genera of trilobites that are peculiar to this side of the Atlantic, but the genera are alike on both sides. An apparent exception to this rule is Paradoxides ( ?) kjerulfi of Scandinavia, of the oldest trilobite layer in that country; but the apparent absence of such a form on this side of the sea is probably due to the scarcity of organic remains in the corres- ponding beds in Acadia. Early Trilobites of the Cambrian Rocks—Matthew. 4 TABLE SHOWING THE RELATIONSHIP OF THE TRILOBITES OF STAGE I OF THE ACADIAN SERIES, AND THE HORIZONS AT WHICH THE SPECIES ARE FOUND. GROUP. GENUS. b c a JES Seen ree pee acl Ot ere a Cem rll aren Sie ee ts ee beeen ee (UM cece eee eens. /VAr, CONCINKUS. Pes of aton cies chaise Fell eveiawe laksiovencovonscaicueo1| CLOW LECH Saat eee eee | Med Le seed COLEUS Seay eel cWec omer nena foie cies ore oracstacevan |e CILEL ILS «mane cea or CULE OU EMT ETNA star oh soceanc wae Rs SRE re | ee oa UL USLLOOUS? rice des eaptatenate iatil| seeps taares caaici eas esedcearere) | Sq Cle fiSSUSa aearss ial Sa CL EL OL SE EO EES Cl SOIC DO ee Son Peco eho oa roa Lae ite Eyeless, short thorax, D 3 —s n = } longifrontes ...... on < parvifrontes ...... Spanmamh pean One Sse estes hae aoe epee ia bes aoe ws PUCCUY QO VosagcToeaetn seni PULCHELLUS.. Spatelsb sur tees tl UCELEN UN AN rs ctaraes =. « (COLCA eT. Beeasee vero ee ieee | CULLCOLULG meret teres aan CLO IE Se (Ctemoce plialins reser alte resteit erie HICL Ceti... cP ere iste 2 im MCrOGISCUS =< cites Ne rarnlos | articephalus..|whitfieldianus. .....|\sp. cf. ceticephalus. fo) © Sa) o 46) 6 ta lenele! 2. Eyeless, long thorax, | | | | | RYPHINE Conocoryphe==... CONOcO- oe . . bint at — PrycHo- eS teeeeeees.- (Ouangond var......\owangondianus. MiNi eres era |fosg eon ee yee nat ate ase eo ge Cane a Eee LILI SOM GcaN Gr valle Speech eck esting 7 ODO LOAVES ete ater lene | ODUIELOO Vid OLESTES names Tae wis | aT ea ene pasate ore rece |OCRMICa- an dean: phalide -. Ellipsocephalus ... ..|sp. cf. poly- tomus. (imate toy eek Ua eat Cheeni wey f ce ec Pea cgees ec ny sill dato xe aber asada ars cupraion, |GCAMICUS-ANGAVAr. Settuece ele ees |ELEUUIVEGUS:. cai. ccc the nearest exposure of which is about thirty miles below Des Moines—to the superimposing variegated shales just mentioned. This formation, as represented in this vicinity, is composed almost entirely of clays and shales, with a few thin layers of soft sandstone and at least three workable beds of coal. The relative positions of the latter are shown in the following section at the Giant coal mine where the fossil forms hereafter noticed were chiefly collected: Drift clay and Carbonaceous ShHAleS.......... secsecsesssceeccsceneseerscceceseees 56 feet WORT (IN Osa thay iccoscecctencsecets surceaceanscecunncuseeemanerenceascbaceccchanencstceceeerenarne aes MNAICR ELC ee ct casecorn yatta toattecaeaet teuurassrthsapeesesesbe sacar semeectccepesasscnecas 20 ft. 6 inches CORIO NO a Al ulesteenestcatnas taacecccateaten Re cronsunes cesses seunnancemtucduaestiecacsoetanes Ae Gee Shales, lower layers fossiliferous 35 feet MO AIR GN@slieds) seseae rece sewer esesecptewcnesetecnecanas cane cde sheaceter su emcnaens cnaneanmcanens 4 ft.6in. to6 feet The Coal Measures of Iowa have a general dip to the south- westward. To the northeast from Des Moines, the coal ap- pears to thin out and finally is wanting altogether, as shown in the accompanying sections; the first at Altoona, nine miles from Des Moines; and the second three miles north of Mitchellville, or sixteen miles from Des Moines. Drift and Carboniferous clays Shales a eiisatceseonsvarseeoses SANG SEONG) satires Mer ceted cat eeees = 1 White’s Geology of Iowa, vol.i, p. 272. 2 Vide White on the “Unconformability of the Coal Measures upon the older rocks,” etc. Geology of Iowa, vol. i, p. 225, et seq. Fossils from the Lower Coal Measures—Keyes. 25 11% feet. 15 “ce 4 “ce A boring near Mitchellville at the eastern border of the county shows an almost entire absence of coal; a statement of the material passed through is also given, though in a different form, in the second biennial report of the state mine inspector. feet. inches, 64 BUN stra se vaslaevwlatacebWavwcedegneiodsacs seers See a Nu een SAUL ue SLUM SU Ls at sip saan rnetdauautc Blue and black shales, ils 6 ERASING OU setae ca eerie etn aotay renter eecoase cae cumstoata nse snrtartedornssedastan-ecnvveensacesec 1 2 ‘Gray, black, blue and sandy shales with two layers of sandstone ........... 141 ral MICS LOMP WIE IM RELY) PADOINES!<..corrsesekaccaeccaseveruc}sseisee-cabenaschevatcuanbarnecass 39 6 Coals No. 2, and especially No. 3, are the most profitably worked, and furnish nearly all the coal mined in the county. Immediately overlying and thus forming the roof of coal No. 3, is a soft black clayey shale, sometimes slaty in places, highly fossiliferous and containing much iron pyrites in the form of crystals and nodules; many cubes of the former being over an inch along the edges, and the latter often containing shells of mollusca. The shell substance of the fossils from these shales, -aside from those contained in the pyritiferous nodules, is re- placed more or less completely by pyrite. In some specimens the replacement is complete, in others only a thin film of pyrite covers the shell leaving the interior of the shell substance with the original calcareous constituents; between the two extremes all degrees of replacement by pyrite occur. In a few instances —Lophophyllum, fish-teeth, and remains of crinoids—no re- placement has taken place. The following tabular synopsis of the fossils thus far discovered and identified will illustrate the amore important faunal features of the shales under consideration: Fossils collected at Des Moines. (The figures in parenthesis refer respectively to the number of genera and species in each group). C(ELENTERATA. (2-2). Discina nitida, Phillips. Lophophyllum proliferum McC. Productus nanus Meek and Worthen. } ‘ i i c cora d’Orb. Rhombopora iepidodendroides Meek. nicabas Nand B: EcHINO DERMATA. (1-1). Chonetes mesoloba N and P. Eupachycrinus (sp? ——— (nov. sp.) g % Vv (sp?) 10-15 Streptorhynchus crenistria Phillips. ERMES. (10-15). Spirifera camerata Morton. Bryozoa. (1-1). ————- lineata Martin Synocladia biserialis allow. —— rockymontanus Marcou. 3 Bowe iperiahs, Awallow Spiriferina kentuckensis Shumard. Brachiopoda. (9-14). Athyris subtilita Hall. Lingula umbonata Cox. Retzia mormoni Marcou. 26 Fossils from the Lower Coal Measures—K eyes. Mouuusca. (20-34). Pleurotomaria graysvillensis N, and P. Lamellibranchiata. (7-9). ele a rae ea AN ae Ep Myalina swallovi McC. Anomphalus rotulus M and W. prcuiqreten cotanus M.and W. cane CEL w ——_ neglectus Geinitz. A spseay Aucniane bellistriata Stevens. Beligrop eu gar cana ee ucula parva Mec. TONE To : : 5 2 ventricosa Hall. ——— percarinatus Conrad. Schizodus (sp. und.) Cephalopoda. (2-5). Clinosphitha radiata Hall. Solenomya: soleniformis Cox. Orthoceras rushensis McC. ——— (sp. und). Gasteropoda. (10-20). Nautilus occidentalis Swallow. : i lasallensis M and W. Dentalium annulostriatum M. and W. —— winslovi M and W. meekanum Gein. eee minuta Stevens. . CRUSTACEA. (2-2). rthonema conica M. and W. ; : is (? ini Streptacis whitfieldi Meek. Anne Gea Gee Aclisina minuta Stevens. eat iy oe robusta Stevens. VERTEBRATA (2-2) Macrocheilus newberryi Stevens. ¢ gracilus Cox. Pisces. ——— (nov, sp.) Petrodus occidentalis? Pleurotomaria brazoensis Shumard. Diplodus (sp?). Summing up the predominant faunal features as presented in the accompanying synoptical table, it appears (1) that in those groups having an optimum habitat marine there was not only a fewness of species but also an extreme paucity of individuals; (2) that brachiopods, though well represented in both genera and species, were not as proportionately abundant as might be expected when it is remembered that this type of life had now reached.its culmination and greatest expansion, and (3) that the fauna was predominantly molluscan. The celenterates, bryozoans, and echinoderms form indeed a very inconspicuous proportion of this local fauna, only three or four specifically distinguishable traces of each group being obtained. Though the brachiopods are represented by fourteen species included in nine genera they are with three exceptions of comparatively rare occurrence; Productus muricatus, Chon- etes mesoloba and Discina nitida only being abundant. The brachiopods are, however, all depauperate, attesting conditions, at the time they lived, extremely unfavorable to their full development, and to the attainment of a normal size that under more congenial circumstances would have been rendered pos- sible. Molluscan life, while the black shales forming the roof of coal No. 3 were being laid down, flourished luxuriantly,, especially the gasteropods which in number of species comprise more than one-third of the entire fauna. Not only did the gas- teropods exceed in species but they far out-numbered all others. ndividuals, while as a rule they were small in size, and some Fossils from the Lower Coal Measures—Keyes. 27 of them even minute, their great numbers made up, in great part at least, for the conspicuity of larger but fewer forms. Though the majority of the forms of this group are small it is not a depauperation as among the brachiopoda, as is shown by the individual size of each species being normal and in some instances even considerably above. Some of these species are also of interest because of their recognition for the first time within the limits of Iowa and hence to a considerable extent their previously known geographical range is increased. Other of the species enumerated are already known to have a wide geographical distribution which is suggestive of a somewhat extended vertical range. Among recent mollusca and especially land forms, a wide geographical distribution, as has been referred to by Binney, appears to be indicative of a high antiquity for the group, and the corroborative evidence is abundant. A notable instance is the living Zozztes, four or more species of which are circumpolar in their distribution, and this genus, even a subgenus ( Cozz/ws ) to which belongs one of these living forms ranges back to the Carboniferous; while the modern genus Pupa is represented in the Carboniferous by four species. Cephalo- pods are not abundant in the shales under consideration, and are represented by only two genera and five species: yet one of the species of Vautilus attained a diameter of 18 cm. or 20 cm. and an Orthoceras reached a length of 50 cm. with a diameter at the largerend of 5 cm. Of the lamellibranchs the majority are small species; but two are comparatively large, attaining a length of nearly 10 cm. and having extremely thin shells. One specimen is of special significance as exhibiting in all the details the internal features of the shell, the characteristic, well defined muscular scars, and the edentulous hinge margin; in fact so closely does it resemble in these characters, and general form and external appearance, a modern Axodonta that it is difficult to see how it can be generically separated from it; and should further investigation prove that the specimens under considera- tion really belong to that genus it would be of unusual interest. The modern Unio, Anodonta and allied genera certainly have a wide geographical and geological distribution, as is shown by the rich discoveries of Unionide in the mesozoic and later strata of the west. The genus Axodonta is, if the opinion of Hall is 28 The Interior of the Earth—Claypole. adhered to, represented even in the Devonian by two species, but that these two species really belong to Azodonta is by some questioned. Dawson has described several allied forms from the Carboniferous of Nova Scotia; their family position however is as yet also unsettled. With these considerations in mind the bearing of the evidence thus far obtained is towards a high antiquity for this interesting group of bivalve mollusks, which now is so abundantly represented in all our ponds and streams. ‘Crustaceans are represented, as is shown in the list, by two species; a Cythere, and a trilobite of which only a single pygid- ium has thus far been found. Vetebrates are also rare—a few fin spines, about 2 cm. in length, and several dermal tubercles, and teeth. ON SOME INVESTIGATIONS REGARDING THE CONDITION OF THE INTERIOR OF THE EARTH. II BY PROF. E. W. CLAYPOLE, AKRON, O. Considering mathematically these evident inferences and treating them according tothe law formulated by Prof. Darwin, Mr. Davison, of King Edward’s School, Birmingham, England, has recently read before the Royal Society a paper in which he shows that in consequence of this law of contraction there must be a couche at some depth where the tangential compression occurring at the surface and due to the rigidity of a crust in- capable of further contraction, must cease, and extension or as he calls it “stretching” must take its place. This result will as he shows occur whenever the horizontal contraction of a shell from cooling equals the diminution of space due to the total descent of all the shells below it from the same cause. A layer in that condition will descend as a whole and assume its new level without suffering either the lateral compression to which the couches above it are subject, (their contraction being less than their loss of room by descent,) or the extension to which those below it are subject, (their contraction exceeding their loss of room by falling into a sphere of shorter radius.) This shell The Interior of the Earth—Clayfole. 29 Mr. Davison calls the “layer of no strain.” He shows that it sinks deeper with time. At the present day he places it at the depth of about five miles. It forms a limit between the bend- ing and crushed layers above it and the squeezed and flattened layers below it. If we understand Mr. Davison aright his conclusions are — first that above this level of “no strain” allthe couches up to the surface are in a state of compression in consequence of their constant sinking, without equivalent contraction, to lower and lower levels, or to the surfaces of spheres of less and less radius. And secondly that below this plane of no strain the couches are in a state of extension—that is are being squeezed out because they are descending into a smaller space while their contraction exceeds this narrowing and would leave chinks or gaps were it not for the immense weight above them under which they are plastic and which squeezes them out laterally so as to fill these chinks or rather to prevent their formation.’ The total vertical descent thus obtained of the upper surface of these extended couches exactly equals that through which the layer of “no strain” is ready to descend without extension or compression by its own contraction from loss of heat; while its horizontal linear contraction exactly equals the difference between its own circumference and that of the shell into whose place it is on the point of descending. Its continuity is therefore preserved. It is obvious that the result obtained must depend on two primary data—the temperature of the surface at the time of consolidation and the time that has since elapsed. The higher the temperature of consolidation the longer must the cooling have continued to obtain the present temperature of the crust, while the same result would be reached by assuming a lower original temperature and combining it with a shorter period of cooling. Mr. Davison assumes, following, he says, Sir W. Thompson, about 175,000,000 years as the time that has elapsed since the consolidation of the surface. On this datum he tells us that the cooling by radiation ceases, that is becomes infinitesimally small 1 It is possible that in the highest portion of this sphere such chinks or crevices may be actually formed, but it is scarcely likely when we con- sider the enormous pressure, which is capable of crushing any known rock. 30 The Interior of the Earth—Claybole. and may be neglected, at the depth of about 4oo miles. From this level it increases upward to a maximum which he places at a depth of seventy-two miles and then diminishes again to an imperceptible amount at the surface. Of course the couche of greatest contraction closely accom- panies that of greatest cooling —-if indeed the two are not identical—and this accordingly is found by Mr. Davison at about the same depth— 72 miles, the contraction diminishing as the cooling, both upward and downward. Pursuing his investigations Mr. Davison shows, as Mr. T. M. Reade had shown a few months previously, that between this layer of greatest contraction, where the space exceeds the matter, and the surface, where the matter exceeds the space (the latter being zero), must lie the layer of ‘no strain” and this he places, as said above, at the depth of about five miles. Below this the contraction from cooling exceeds the diminution of space by descent and the layers are consequently squeezed out or flattened to fill the vacancy. Above this the strata are crumpled or crushed because they are too large for the smaller space into which they are sinking. The Rev. O. Fisher of Cambridge, England, in a review of the papers above quoted obtains results which differ considera- bly from those above given. Assuming the temperature of solidificacion at 7000 degrees F., he finds the depth of the shell of greatest cooling and contraction at fifty-four miles, and that of the level of “no strain” at two miles; while assuming an initial temperature of 4ooo degrees F., the former would lie at a depth of thirty-one miles and the latter at a depth of 0.7 of a mile. These discordant results show us that geology is not yet in a state to speak with confidence upon the exact condition of the interior of the earth at given but inaccessible depths. In the former case the result would be attained in ninety-eight millions and in the latter in thirty-three millions of years. Mr. Davison also remarks on the indisputable fact that in a cooling globe this layer of “no strain” which was once at the surface is constantly descending with time and he states that “within certain limits its depth increases with the square root of the time;” whereas according to Mr. Fisher’s calculation it varies as the time. Its descent in the latter case must be much more rapid than in the former. The Interior of the Earth—Claypole. 31 We will defer consideration of one or two of Mr. Davison’s data for the present, in order to regard from a geological stand- point the already quoted statements of the mathematician. While no doubt can exist concerning the reality of this layer of “no strain” within the crust of the earth, yet a careful con- sideration of the whole subject and of the inferences deducible therefrom, suggests to the physical geologist some reasons for thinking that in determining its position the mathematician has placed it too near the surface. We take Mr. Davison’s meaning to be that it lies at a depth of five miles beneath the solid crust of the sphere, disregarding the waters of the ocean, and that it therefore roughly follows the inequalities of the surface. This is indeed obvious, for the ice-cold water that fills the abysses of the ocean must by con- duction and convection chill the crust below it at least as much as the continental areas are cooled by radiation. This seems to be confirmed by the fact that the beds of the great oceans are denser than the continents. We may therefore conclude that the layer of “no strain” not only rudely follows but somewhat exaggerates the contour of the surface, and lies at a less depth beneath the dry land than beneath the deep sea. If then it lie at the average depth of five miles it must under the continents lie at somewhat less than that depth. Further, from the very nature of the case it was in the past during the paleozoic ages for example, nearer the surface than it is now. Yet again from its own nature—being a shell of perfect freedom from all stress and strain and consequently from all motion except the gentle subsidence caused by the contrac- tion of the shells below it—it can never be elevated into anti- clines or depressed into synclines. Notwithstanding this inference we have in Pennsylvania strata now exposed, which at the close of the paleozoic era were buried, not only five, but even eight miles deep. The Trenton limestone, for example, was covered in some places with from 25,000 to 35,000 feet of newer strata. Yet it was subjected to compression and contortion and has been thrust up from that im- mense depth into huge arches and troughs. And there is little reason to doubt that beds lower still were included in those movements that produced the Appalachian revolution and closed the palzozoic erain North America. 32 The Interior of the Earth—Claypole. Similar facts may be cited from English geology where the Lower Silurian and Cambrian rocks have been forced up from depths almost as great as those given above. The Huronian series of North America affords another case in point. Some of these have been brought to the surface from a depth greatly exceeding that which Mr. Davison assigns to the layer of “no strain.” A second point suggests itself as worthy of consideration, not asa necessary objection to the theory as a whole but as another fact requiring either a change in the depth assigned to the neutral layer or some corresponding modification in another department of geology, before Mr. Davison’s conclu- sions can be accepted. The layer of ‘no strain” must be from its very nature, as already remarked, a perfectly quiescent shell in which no movement can possibly occur except the gentle secular settlement incident to its condition. No compression and no extension being the law of its existence it must form the only undisturbed shell in the outer portion of the terrestrial sphere. Above it the strata are subject to crushing and below it to squeezing. Being without movement it is of course quite impossible to find in it the seat of any of those disturbances that manifest themselves at the surface. Moreover the shell below it exists under such conditions that all movement in it must so far as we can see be very gradual and gentle. The temperature of its highest layer being about 500° F. and in- creasing downward and its mass, at least in the upper part,. being more or less saturated with water, it must be for the most part in a state of aqueo-igneous or even of igneous plastic- ity. In such a mass under so constant and enormous a pressure no sudden or violent motion can take place. Any slight change in the intensity of the pressure will be met and corrected by gentle movement or “flow” of the plastic mass. It seems con- sequently hopeless to seek here any centre of disturbance or commotion. We are therfore driven by exclusion to place all such foci in the upper or compressed layer. That is in other words, we must seek the seat of the earthquake and of the vol- cano within five miles of the surface, in the layer where by hypothesis the strata are too cool to suffer much further com- pression by cold and are consequently bent and crushed as they The Interior of the Earth—Claypole. aa sink to a smaller spherical surface by the contraction of the hotter sphere beneath them. Here and here alone according to the theory now under consideration, among these yielding and breaking strata, can we seek with any hope of success the focus of the earthquake that spreads destruction and ruin at the surface, and of those volcanic vents which from time to time pour forth their streams of lava. This doctrine has long been familiar to seismologists. Here they have been accustomed to place the cause of the sudden jar that produces the one and the changing conditions of pressure to which in the present state of our knowledge we attribute the other. But it will cause them not a little difficulty to learn that they must descend no deeper than five miles for this purpose. They will feel a serious objection to being told by the mathematician that they must limit their seismic investigations to so thin a layer of the crust. Possibly to this they must come at last but much readjustment will be necessary for the purpose. Few vulcanol- ogists have yet placed their foci so near the surface. The late Mr. Mallet inferred from his observations that the shock of the great Neapolitan earthquake of 1857 radiated from a centre at the depth of seven miles, and the calculations of Capt. Dutton and other geologists of the U. S. survey have led them to place the seismic focus of the late Charleston earthquake at the depth of twelve miles. Probably neither Mr. Mallet nor Capt. Dutton would urge these results as anything more than approxima- tions. But they and physical geologists generally will scarcely be willing to abandon their calculations without stronger evi- dence. The difference caused in the phenomena of an earth- quake by the transfer of its focus from a depth of twelve miles to one of only five miles from the surface would be so great that it could not well be altogether due to errors either of ob- servation or of calculation. One other remark of Mr. Davison’s deserves a moment’s notice in passing. He makes the statement that “ owing to the continental wrinkles the amount of stretching under them must have been very much less than under the great oceanic areas.” But it is not easy to see how this can be the case. It seems an unavoidable inference from the nature of the layer of “no strain” that below it there can be no violent disturbance and that the 34 The Interior of the Earth—-Claypole. motion there, though very great, must be gentle rather than sudden, and must also be equally distributed. If moreover this layer be nearer the surface beneath the continents than beneath the oceans then a less thickness of the crust is subject to crush- ing than to “compressive extension” in the former than in the latter case. This leaves a greater mass below the level of “no strain” which is suffering extension. The violent commotion that often disturbs the upper crust can not in the least affect the deeper masses. The only condition that seems competent to reduce the amount of extension beneath the land-masses would be so great a depression of the level of “no strain” as to leave less material below it subject to extension, and this the nature of the case as already shown, does not admit. In reflecting on the subject we must bear in mind that the results above stated are only obtained by assuming as the tem- perature of original solidification of the crust a very high figure —in Mr. Fisher’s investigation 7000 degrees F. This datum seems scarcely admissible when we recollect that material simi- lar to that which composed the primeval crust now solidifies at about 2000 degrees F. Even allowing for the effect of un- doubted greater pressure at that date and perhaps for some other conditions different from any now prevailing, it seems more in accord with physical laws that the original slaggy liquid cooled to a much lower degree before solidification took place. By changing this datum to 4ooo degrees F. Mr. Fisher obtains only 0.7 of a mile as the present depth of the level of no strain, a re- sult yet more discordant with the views of physical geology than the former, and in the face of known facts scarcely tenable. Again, as said above, Mr. D. assumes an excessively high fig- ure for the duration of the cooling process—175,000,000 years —a period which, though not impossible, is yet much beyond that which is usually believed to have elapsed since the epoch of consolidation. Considering all these points it may be well to hesitate before yielding full and implicit acceptance of these new results of the mathematician. The physical geologist is grateful for all con- clusions that his mathematical brethren can give him, but he 1 Mr. J. M. Reade’s term. Post Glacial Geology of Ann Arbor—Wooldridge. 35 cannot always adopt them at their first publication. Though the rigid processes of their science admit of little or no dispute yet the final results are dependent on the data and on the form in which those data are supplied. And in the present problem some of these data are so uncertain that considerable doubt must attach to the final outcome from the mathematical mill. And when as in the case now in hand the conclusions are or seem to be at variance with accepted and apparently solid doctrines in the science, the geologist may be excused for hesitating before he accepts the mathematical deduction. We will not now follow Mr. Davison into that part of his paper in which he treats of the elevation of mountains by the contraction of the cooling globe—a topic in which he is in di- rect opposition to Mr. Fisher —but at some future time we may return to the subject and state the arguments of the mathema- tician on this point. THE POST-GLACIAL GEOLOGY OF ANN ARBOR, MICH. BY C. W. WOOLDRIDGE. Many students in the University of Michigan must have noticed how different is the character of the ground on which the city of Ann Arbor is built from that of the surrounding country, either upland or lowland, The greater part of the city is built on a low hill witha flattened convexity of contour. The Huron river entering from the northwest crosses the city in a deep and picturesque valley. On the east side, between the city and the observatory hill, ex- tending from the river half a mile or more to the southward, is, or was, a typical Kame formation, some of the best marked features of which, unfortunately, have recently been destroyed by grading. The western part of the city is crossed by a brook flowing northward to the river, which is formed by the union of two branches, one flowing from the southwest, the other from the southeast. From the valley of this brook, the southwestern and southern border of the hill, on which the greater part of Ann Arbor is 36 Post=Glacial Geology of Ann Arbor—Wooldridge. built, is marked by a declivity from the foot of which spreads a flat valley broadening toward the southeast, in which direction it extends to lake Erie. The neighboring hills and uplands east, west, north, and across the flat to the southward, are com- ~ posed of the boulder clay with here and there a bank of gravel or sand, due to its local erosion, but all over the city within the boundaries defined every excavation shows stratified gravel or sand, a deposit so different from anything else in the vicinity, and so extensive that it could not be due to any merely local or accidental causes. In the summer of 1887 I began an examination of these de- posits. Two deep gravel pits in different parts of the city having at that time freshly excavated faces, offered good sections for study. The first of these examined is excavated in the bluff facing the river valley two blocks east of the Michigan Central R.R. depot. This section faces the north but bends around on either side so as to face the west and the east. Its lower part through a depth of ten or twelve feet exposed above the talus is composed of a fine, nearly uniform and clean gravel, of pebbles averaging about the size of peas and beans. This is arranged in distinct beds of varying thickness, nearly horizontal in position but terminating in thin edges, overlapping each other. Each of these beds, however, is obliquely laminated as if it were built out from ashore by successive accretions de- posited on its border, the pitch of that border being shown by these laminations. What surprised me was that the dip of these laminations is uniformly toward the south, that is toward the hill on which Ann Arbor is built, as if in that direction had been open water, while to the northward where now the valley of the Huron river is excavated to a depth of 50 or 60 feet be- low the level of these beds had been the shore. Above these gravel beds is a stratum of bowlders ranging from pebbles the size of a hen’s egg to blocks that would weigh a quarter of a ton, with barely enough of finer materials, gravel, sand, and clay, to fill the interstices. This bed is a distinct stratum five or six feet thick deposited in conformity with the gravel beds beneath it, and covered by the surface soil. Rest- ing on the beds of finer gravel as it does, it seemed a strange deposit, for it is obvious that any current powerful enough to Post=Glacial Geology of Ann Arbor— Woodridge. 37 have brought these bowlders here must have carried the gravel on which they rest. I could only account for their presence by supposing them the residue of some mass of bowlder clay which towered above the water close by, and had fallen upon these gravel beds as a land-slide, the finer materials of which the waves had carried away. A little farther west, where the western approach to the Michigan Central depot has recently been excavated, the cutting is made in bowlder clay which might be the stump of such a mass as could produce a bowlder bed in the way supposed; this clay seems to rise from beneath the gravel nearly to the hight of the beds which we have ex- amined, The other gravel pit available for study is in the north- western part of the city. Here the principal face of the exca- vation fronts the southeast while its southern extremity bends round to face the northeast. This southern part of the cutting is excavated beneath an older gravel pit, and here deeper beds are exposed than elsewhere. The northern part of the cutting shows a section extending from the natural surface down to the beds exposed farther south. The total depth exhibited I esti- mated at 35 feet. These deeper strata are composed of sand, thin bedded, the layers succeeding each other at intervals of less than half an inch, having a very perceptible dip to the southward, and sprinkled thinly with pebbles ranging from the size of a butternut to that of the sand itself. These strata have the appearance of beds deposited on the slope of a lake bottom below the action of ordinary waves down which a few pebbles have slid from a higher level. Some of these beds have been cut away on the south side and refilled with similar beds having the same general slope as before. The junction between these sand beds and the gravel overlying them was hidden by a talus at the foot of the cutting in the northern part of this excava- tion, beneath which these sand beds enter with a rising slope of 10° or 12° toward the north. ; Above this talus is a series of thicker beds of gravel similar to those examined in the other excavation. These beds are nearly horizontal and show oblique laminations dipping toward the south as before, but at this point a broad valley opens to the southward, while a short distance to the north rises the highest hill in the vicinity of Ann Arbor. 38 Post=Glacial Geology of Ann Arbor—Wooldridge. Above these beds of gravel is a bed of horizontally stratified material, here about ten feet thick, composed of mingled clay, sand and gravel. No stones larger than a hen’s egg appear in any of these beds. I was inclined to attribute this surface stratum to the wash from land-slides which had fallen from the clay hill to the north, but on further examination I find that a surface stratum containing much clay and larger pebbles some- times reaching the rank of bowlders, is spread quite generally over the Ann Arbor gravels. Some change of conditions must have attended the deposition of this surface stratum to produce this change of its character, but just what that change may have been Iam not prepared to suggest. Elsewhere I have seen a similar condition of the surface stratum in yet more marked contrast to the sedimentary beds on which it rested, and | think that the phenomenon is general enough to be de- serving of special study. I will sum up the results of my studies of the Ann Arbor gravels by saying that I have come to see in them a well marked example of an ancient delta. . When these beds were deposited lake Erie extended over the site of Ann Arbor, which at that time was a bay near its west- ern extremity. Into this bay the Huron river poured a turbid torrent from the, then naked, hills of bowlder clay to the north- westward, dropping its gravel as soon as it entered the waters of the lake, while its finer sediments were carried farther. This gravel and sediment formed the delta, now the hill; on which Ann Arbor stands. When the water subsided the river formed a new channel to the northward of an island, the north- western extremity of which is now the observatory hill, and soon cut a gorge in the loose drift materials from which ravines extended on either side to shape the hills which now border its valley. There may very likely have been a shallow body of water retained in the old bay south of the Ann Arbor delta, and one of these side ravines making connection with that would drain that water into the river and thus cut the valley through which flows the brook in the west side of the town. I have looked for traces of the old shore line corresponding to the level of the lake when this delta was formed. At a few points along the hills which formed the southwestern border of the bay at that time are what may be traces of shore terraces Correlation of the Lower Silurian —Ulrich. 39 then formed, but they are véry obscure, not likely to be noticed by anyone who does not know exactly what he is looking for and where to look for it. Along most of that ancient shore no such traces can be detected. In the neighborhood of the river the country must have been greatly transformed, since shores existed at that hight, but on the opposite side of the bay and the opposite border of the island mentioned, such changes might be expected to be less extreme. _From the fact that shore marks there are so obscure I infer that they were never strongly marked, or else that the earthin this region was then in a condition too loose and unstable to retain their traces. Note.— Since the above was written, I have discovered evidence proving the existence of shore lines at two different levels, both passing through the site of Ann Arbor. The upper one of these coincides with the delta plateau above described, while the lower has left its trace in an obscure terrace noticeable at intervals along near the base of that plat- eau at a level about thirty feet lower. It is further evident that at the epochs of these shore lines the water margin in this region was a suc- cession of deeply indented, land-locked bays, flanked and intermingled with an archipelago of islands, which have served greatly to complicate and obscure the traces now remaining of these shores. C. W. W. A CORRELATION OF THE LOWER SILURIAN HORIZONS OF TENNESSEE AND OF THE OHIO AND MISSISSIPPI VALLEYS WITH THOSE OF NEW YORK AND CANADA. BY E. O. ULRICH. IV; Beds XII. The strata comprised in this division are a little more than 200 feet thick in the vicinity of Cincinnati. Com- pared with beds XI, it is found that they differ considerably in the much greater abundance of calcareous material, the layers of limestone, particularly in the lower portion, being compara- tively much more numerous, the ratio of limestone and shale being on an average about one foot of the former to two feet of the shale. The latter also appears more calcareous and weathers to a yellow or drab color. 40 Correlation of the Lower Silurian— Ulrich. Like beds XI, these also, mainly upon paleontological grounds, admit of division in two minor sections which I refer to as XIla and XIIé. Of the 199 species mentioned in the list as occurring in beds XII, 113 are restricted to them, while only 58 are com- mon to the upper and lower sections. Fifty-seven are restricted to XIlIa@, and forty-six to XIIé. a. The thickness of this sub-division as seen in the hills sur- rounding the cities of Cincinnati, Covington and Newport is about go feet. In the lower 50 feet (exposed in the hills 270 to 320 feet above low water mark in the Ohio river) there is often a considerable amount of sandy material, the limestone layers being nearly all impure; and some of the layers might even be described as fine grained sandstones. The intercalated shales, too, are less fine grained and of lighter color than usual. Fossils of many species, principally bryozoa, however, are mod- erately abundant and in a good state of preservation. The most distinctive forms are distributed about as follows: The five feet at the base (Zz. e. 270 to 275 feet above low water mark) hold great numbers of Cadlopora dalet, C. subplana, and Peronopora vera, a species with larger cells than P. dectpiens. ‘The second of these species is restricted to this horizon, but the others range about fifty feet higher. Twenty feet above the C. swbflana bed many species make their appearance. Of these Heterotrypa frondosa, Dekayia as- pera and Homotrypa curvata may be mentioned as particularly characteristic of the horizon. In the succeeding twenty or twenty-five feet fossils are comparatively rare though several of the layers are sometimes charged with more or less worn ex- amples of Orthis testudinaria. It is in this portion of the sec- tion that the sandy feature of the sub-division is the most conspicuous. Many of the layers show peculiar trails and fucoidal markings. The top of these layers is marked by a very persistent shell, the Streptorhynchus planoconvexus, which, though restricted to a vertical range of perhaps not over five feet, may be found wherever this horizon is exposed. The remaining portion of the sub-division, z. e. between 320 and 360 feet above low water mark, furnishes the bulk of the rock used in constructing foundations at Cincinnati. Sub-crys- Correlation of the Lower Silurian— Ulrich. 41 talline limestone, of bluish color 1s present here in many courses, varying in thickness from three to ten inches, The intercalated shales are generally quite rich in fossil remains, causing the quarry dumps to be much frequented by collectors. The fol- lowing are the most characteristic species of this horizon: Glyptocrinus decadactylus Hall. Orthis bellula Meek. “ ? shaffert Miller. “ella Hall. Heterocrinus grandis Meek. “ pfisstcosta Hall. Hemicystites stellatus Hall. “ plicatella Hall. Atactoporella mundula Ulrich. Platystrophia crassa James. Constellaria florida Ulrich. Streptorhynchus sinuatus ? Emmons Bythopora fruticosa Miller & Dyer. & Meek. Leptotrypa discoidea Nich. Lingulella cincinnatiensis H. & M. Discotrypa elegans Ul. Holopea paludinatormis Hall. Dicranopora internodia Miller & Cyclonema bilix Meek (? Conrad). Dyer. Orthoceras dyert Miller. Ptilodictya falciformis Nich. Cyrtoceras vallandinghami Miller. S maculata Ul. Anodontopsis ? untonoides Meek. “ pavonia d’Orb. Proetus parviusculus Hall. Phylloporina clathrata M. & D. Anomaloides reticulatus U1. 6. This sub-division embraces the upper 110 feet of beds XII. The whole is of a light blue color and consists of rapidly alternating layers of soft shale and limestone. The latter are generally in pure, very thin and irregularly bedded, (shelly } and charged with a profusion of animal remains, some sections of the beds being almost literally composed of fossils. Only a few of the limestones are thick and even-bedded enough to fur- nish desirable building rock, and, so far as I am aware, the sub- division is nowhere extensively quarried. Still the tops of the hills about Cincinnati, where much grading for streets and buildings has been done, furnish an abundance of excellent ex- posures of the lower fifty to eighty-five feet. The highest of the Cincinnati hills (Mt. Auburn and Price hill) do not contain any of the upper twenty-five feet of the subdivision, and only a few localities in Ohio and Indiana are known where they may be studied. A creek, the name of which does not just now come to my mind, cuts through them at a point about one mile northwest of Manchester, Ind. They are also shown in Todd’s fork near Morrow, O.; and in several small water courses near Lebanon, O. These exposures show that above the well known “Orthis bed” the fossils become 42 Correlation of the Lower Silurian — Uirich. gradually much less abundant. The lithological features, how- ever, are not remarkably different from those pertaining to the lower eighty feet. ; The beginning of the subdivision, as shown in the Cincinnati hills, about 360 feet above the river, is marked by the first ap- pearance of a number of easily recognized fossils, among them being Strophomena fracta, Orthis sitnuata, Platystrophia lati- costata, Homotry pa obliqua, Batostomella gracilis, Monticult- pora molesta, and Heterotrypa? vaupel?, Of these the first and the last two are restricted to the lower ten feet, but the others range upward eighty feet or more. It is at about this horizon also that Glyptocrinus dyeri, G. subglobosus, Ohiocrinus con- strictus, Stenocrinus pentagonus and Locrinus subcrassus are found. Between 370 and 380 feet above low water mark there comes in a bed holding countless shells of a form of Strophomena which, on account of its exceptionally heavy shell, is known to collectors under the name ponderosa. Many of its valves (usu- ally the concave side) are encrusted by the delicate zoaria of Stomatopora and Atactoporella, but lamellibranchs, gasteropods and other brachiopods are almost excluded from the bed by the prolific multiplication of the Strophomena. The next recognizable horizon occurs at an altitude of about 385 feet above low water mark. This might be called the Strophomena nasuta horizon, that restricted shell being very abundant here. From here on to the 400 feet level the shales, of a lighter color than usual, predominate. These shales pre- sent a wonderful development of life, the fossils being both beautifully preserved and of great variety. The class bryozoa, however, furnishes by far the greatest number of individuals as well as species. Fragments of Callopora ramosa, C. rugosa, Peronopora compressa, Monticulipora cincinnatiensts, Hetero- trypa inflecta, Dekayia appressa, Batostomella gracilis, Lepto- trypa ornata, L. calceola, L. clavacoidea, and Chetloporella flabellata are more or less abundant. With one or two excep- tions these species are also all restricted to this bed. Other characteristic fossils of this horizon are Orthis jamest, Bucania ? costata, Ambonychia ? jamesi and Anomalocrinus caponiformts , The last well marked and, perhaps, the best known fossil . Correlation of the Lower Silurian— Ulrich. 43 horizon is the “ Orthis bed” which comes in at an elevation of 430 to 435 feet above low water mark. This bed is generally several feet in thickness and remarkable chiefly because it con- tains great numbers of a very large and gibbous form of Platy- strophia lynx. Occasional examples of this species or variety are met with both above and below this bed, but none are known to have been found beyond the limits of beds XII. In Kentucky the lower subdivision of the series of strata here designated as beds XII form, almost exclusively, the surface rock of Campbell, Kenton, Boone, Gallatin, Grant, Pendleton and Bracken counties. In the range of counties to the east and west of those mentioned the upper subdivision and a portion of beds XIII still remain, while the upper members of beds XI come to the surface over a good portion of those abutting on the south. They form also a rather narrow strip of surface be- yond the valleys of the Kentucky and Licking rivers, which, beginning on the western side of the group of counties men- tioned, passes in a rudely circular manner through the counties of Owen, Henry, Shelby, Spencer, Washington and the north- eastern portion of Marion; asa very narrow strip through Boyle into the extreme northern portion of Lincoln and the western portion of Garrard; from here into Madison, then on through Clark, Montgomery, Bath, Fleming and Mason into Bracken county. The Kentucky geologists include the lower fifty feet (all below the Streptorhynchus planoconvexus horizon) in their middle Hudson, while the remaining 150 feet form the lower portion of their upper Hudson series.' In Washington, Boyle, Lincoln, Garrard, Madison and Clark counties the strata of this division are decidedly arenaceous, the feature being much more pronounced and of greater extent than in Ohio and Indiana. In fact some portions of the lower sub- divisions (which here, too, can not well be distinguished from the upper) may with truth be called sandstones. In these a 1T cannot see any good paleontological reason for the divisions pro- posed by the Kentucky geologists, and have in consequence not accepted them. The lithological peculiarities of these three divisions disappear rapidly to the northward of the central counties of the state, so that in Ohio and Indiana their strict identification is no longer possible. 44 Geology as a means of culture—A. Winchell. few fossils occur as casts, but, being illy preserved and difficult. to obtain, are not likely to be much sought for. Above the S. planoconvexus layer, which is nearly always a well marked horizon, the fossils are quite plentiful, but the: finer features of their external structure and ornamentation are generally obscured by adhering grains of earthy matter, or thin deposits of lime. Many also are silicified. Among a large number of the species which have been mentioned as character- istic of the division in Ohio, there are several which, so far as. known, occur there only very rarely, or not at all, yet are very abundant in the Kentucky exposures. Of these ARhynxchonella fringilla Billings ( Orthis linneyi James), Helicotoma helena (Bill. sp.), Ptilodictya hilli, Amplexopora cingulata, Hetero- spongia subramosa and Cyrtoceras conoidale should be men- tioned. Most of these species occur in beds which I hold to be very nearly equivalent to those exposed in the Cincinnati hills at an elevation of about 350 to 360 feet above low water mark. (To be continued.) GEOLOGY AS A MEANS OF CULTURE. BY ALEXANDER WINCHELL. iL 1. INTRODUCTORY. The editorial management of the AMERICAN GEOLOGIST an- nounced in the Prospectus, as an important feature, the intended publication of matter expressly suited to the needs of teachers. of geology. Their plans also, embraced the presentation of views setting forth the true relation of Geology to educational work, and to general intelligence. It was believed such efforts would commend the science to all teachers and readers; and enlarge its acceptance and influence in the field of education. In view of the needs of teachers, it is intended to offer synopses, expositions, analyses, tables, schemes and other devices and matters of practical utility in the processes of instruction; and for this purpose, the editorial board anxiously await the acces- sion of sufficient financial support to justify the employment of Geology as a means of culture— A. Winchell. 45 illustrations on a generous scale. They believe the profession of teachers will respond to their efforts. The editorial board are aware that a “departure” of this kind may be regarded as compromising the scientific standing of the journal. They hear it said there are too many popularizers dealing with scientific material at second hand; and that we want many more investigators and more original contributions. The writer of this is also of the opinion that original work ‘should be actively and directly promoted; but with the founder of the Smithsonian Institution, he perceives that the best inter- ests of science demand that knowledge be “diffused” as well as “increased.” The diffusion of knowledge promotes its increase by multiplying the number brought into position to contribute by money and brains toward effecting the increase. When the diffusion is extended into the ranks of intelligent teachers, the best possible conditions of increase are brought into exis- tence. In the January Number of THE GEOoLocistT, was inserted under the general head of Editorial Comment a note entitled, “Geology in the Educational Struggle for Existence.” It was intended to point out the nature of the rivalry which tends to restrain, es- pecially in certain universities, that advance of geological studies which their inherent relative importance would lead us to ex- pect. That note simply pointed out a state of the facts. How greatly the interests of education and general culture are made to suffer by the existence of such a state of facts the writer did not undertake to show. But the exposure of the facts ought to be followed by an exposure of their wrong and unreasonable- ness, and the injury which they inflict on the cause of education an injury inflicted at such a stage of educational development as to result in permanent malformation and deformity. The present writer will attempt, therefore, to carry the discussion to its natural development, and will begin, in the present article, a candid examination of the relation which geological study sustains to symmetrical culture. To the positions here taken he invites the thoughtful attention of all teachers and all geologists. 2. WHAT IS MEANT BY CULTURE? It is considered educational orthodoxy to maintain that educa- 46 Geology as a means of culture—A. Winchell. tion, as the term itself implies, consists in such training of the human powers—but more especially the intellectual faculties—as. will make them of greatest service to their possessor. If this expression means exclusively culture, and does not involve the acquisition of useful knowledge, it should at least be said that the acquisition of knowledge is one of the incidents of culture, and hence culture ought to be so sought as to involve the at- tainment of wseful knowledge. For the present, however, the writer wishes to contemplate the purely cultural aspect of ed- ucation, and to inquire how geological studies stand related to processes of pure culture. In order that one’s faculties may become most serviceable, they must acquire as far as possible, alertness, effectiveness and readiness. In other words, they must act with facility and ra- pidity ; they must accomplish a large volume of their appropriate results in a given time, and must be ever ready to enter into action. They must be like a team which is quick, strong, and in harness. What in detail, do educators contemplate when they speak of culture? What are the several powers whose alertness, effectiveness and readiness are best promoted by best culture? This is equivalent to asking what are the powers by whose most perfect activity we achieve most successfully the work al- lotted to us? The obvious answer is, all the powers by which a human agent seeks his ends—powers physical, powers intel- lectual and powers ethical. Let us restrict the inquiry, for the time being, to the powers intellectual. We will contemplate then, for the present, pure zztedlectual culture. The term culture is much employed by.a class of writers and speakers who extol lines of study demanding the exercise especially of verbal memory, and the power of compari- son and analysis. The verbal memory is the faculty of retain- ing and recalling mere words. It is the means of acquiring names and of speaking them on occasion. It fixes phrases and quotations, and puts us in possession of them, It seizes on the words and forms of a foreign language, and makes them per- manently ours. It is the spring of the faculty of verbal utter- ance; it confers effective power of expression. Its function extends to the retention of dates and other numerical expres- Geology as a means of culture—A. Winchell. 47 sions. Self-evidently, the verbal memory is an important means. in the acquisition and communication of all knowledge, and the attainment of all ends to which knowledge contributes. To. add alertness, effectiveness and readiness to the verbal memory is one important factor in intellectual culture. Verbal memory, however, appears to be psychologically an- alogous to the memory or reproduction of sounds and sights in general; and thus, for our purpose, the general power of repro- ducing percepts may be designated the sexse-memory. This. power in its further exercise, is that by which we recall the feat- ures of individuals, and attain an extensive acquaintance. It pre- serves what we have seen in the forms of matter in general— forms of animals, plants, scenery, architecture. Readiness of recognition is conferred by it, and therefore, power of detail in descriptions. It is the chief faculty of story-telling —so far as. simple utterance is concerned. Facility in sense-reproductions confers many advantages; and it is often the means of attaining successes which a superior grade of reflective intelligence fails to win. Aside from the store of facts which it sometimes holds at the service of the other powers, it is the most available in- strument for what we call popularity. Though the vice of the excessive exercise of sense-memory may be garrulousness, re- cital of meaningless details, the substitution of anecdote for thought, and general shallowness, yet it is quite manifest that the fullest exercise of the sense-memory can only be produc- tive of advantages, if the judgment and other intellectual powers are brought into symmetrical and restraining develop- ment. The whole field of the sense-memory deserves careful exercise and strengthening, and this work must be one of the useful and legitimate elements of broad culture. Embraced in the order of culture first referred to is the exer- cise of the power of comparison and judgment. Without af- firming that these are one faculty, their constant association in activity leads me to speak of them as one process. In detec- tion of likenesses and unlikenesses, we discover grounds for judgments. Every judgment pronounced is an assertion of congruity or incongruity. As every act is the explicit or im- plicit expression of a judgment, a ready facility in the appre- hension of the grounds of judgments is a cultural acquisition of prime importance. 48 Geology as a means of cultuwre—A. Winchell. The power of adstraction is another factor in that intellectual effectiveness which attaches to the lines of study extolled by the same class of writers about culture. Abstraction is the contem- plation of one thing apart from all other things. It is simply an effort of attention carried to complete success. Attention is specially indispensable in the search for relations which are not immediately obyious—relations between things inconcrete, or abstracted from tangible forms. Every continued process of reasoning depends on abstraction. All mathematical relations, mental powers and moral qualities are abstract. The power of abstraction is a faculty in constant demand, but especially in the higher efforts of thought. It is an important power falling plainly within the scope of general culture. The faculty of deductive reasoning, while constantly em- ployed in many familiar modes of mental activity, is also one especially demanded in many of the higher efforts of intelli- gence. It is preeminently the faculty of mathematics; but it finds constant exercise in logic, in philosophy, in physics, and wherever principles or abstract truths are given, and their con- sequences or outcome are demanded. Obviously, mental culture must embrace the improvement of this royal power. But deductive reasoning implies a power of retention of abstract truths or principles. This is often designated the philosophic memory. As an accessory and inseparable adjunct of ratiocinative processes, this power is indispensable in the higher mental activities; and its capability of perfect exercise must be one of the conditions of most efficient mental service. In other words, complete culture embraces an improved power of philosophic or thought memory. It will scarcely be doubted that general culture involves the quickening of the zmagination, the training of it to moderation and consistency, and the employment of it as an adjunct in the efforts of memory and deductive reasoning. The picturing power of this faculty gives vividness to the reproductions of sense-memory, and readiness in the comprehension of descrip- tions. It is aninvaluable instrument in the attainment of clear conceptions of the results unfolded by deductive processes. The interpretation of the results reached by mathematical reasoning often depends wholly on the illumination of the field of ex- Geology as a means of culture—A. Winchell. 49 ploration by the light of this faculty. It goes before discovery, and discloses resting-places for thought in the midst of the gloom of the unknown. Its creative powers are often exer- cised under the promptings of analogy, congruity or contrast, and it thus becomes luxuriant in simile and metaphor. By its luminous apprehension of the forms and details of concrete things inaccessible to perception, it contributes to graphic de- scription; and through its resources of metaphor, both illumin- ates the thought and garnishes the style. Imagination is there- fore a powerful instrument in the creation of new conceptions and the transmission of them to the intelligence of others. A mind well fitted for the creation of new conceptions possesses one of the most effective gifts of culture; and if, in addition, it wields the power of graphic and pleasing elucidation, its cultural gifts are brilliant, attractive and useful. Assuredly, then, the imagination is one of the most important faculties to improve and strengthen by the arts of education. I have mentioned the intellectual powers and processes some- what in the order in which they are the subject of disciplinary exercise in the popular systems of “liberal” culture, rather than in the order of their importance or the order of their spontan- eous development. dwelling especially upon the California finds which associate man with the Pliocene period. He deplores the skepticism which has hitherto excluded this evidence. But it is better to be over-skeptical than over-credulous. The reluctance to admit the proofs of Pliocene man has led to the same sharp scrutiny of the age of the auriferous gravels which has been so beneficial in the cases mentioned above. May not the Pacific slope have run so different a course of development that the so called Pliocene there overlaps the Quaternary of the Atlantic slope? Already we have the opinion of Dr. Alexander Winchell, in the March number of this journal, that the great western out- flows of lava occurred in the Glacial period, and of Gilbert and McGee of the U. S., Geological Survey that the Equus fauna should also be co-ordinated with the same period. The general result of the controversy about the antiquity of Sa Review of Recent Geological Literature. man has been to correct the estimates of geological time. Let the discussion go on. Let us not discourage it even by the suggestion that it is beneath the dignity of the true geologist to make estimates of geological time in years. REVIEW OF RECENT GEOLOGICAL LITERATURE. Considerations sur les fossiles decrits comme Algues. By G. MAILLARD. (Abhandl, Schweizer, Paleontol, Gesell, vol. x1v. 1887. Basel,and Gen- eva, pp. I—40, pls. i—v.) One of the most valuable contributions which has lately been made to paleontological science is that of M. Maillard, curator of the museum of Annecy, on those fossils described as alge. After reviewing briefly the history of the synonymy of these organisms, so many of which are “problematic,” the author divides them according to superficial characteristics into two categories: 1. Thosein the form of simple semi-cylindrical or more or less flattened elevations occurring on the lower surface of the strata, and which are identical with the matrix in chemical constitution, grain, and color, without any mixture of a foretgn substance peculiar to the presence of the fos- sil; they cannot be isolated from the strata, but comprise simple contour or bas-reliefs on the under side of the strata. These forms which he calls “demi-reliefs” include (a) most of the palzozoic forms, such as Crossochorda, Cruziana, Harlania, with perhaps Spirophyton and Alec- torurus; (b) Helminthopsis, Gyrochorte and Cylindrites in the mesozoic ; (c) the Helminthoidz, Paleodictyon, and Miinsteria in the Tertiary. The second category includes those which may be isolated from the rock, and which are more often cylindrical or membranaceous, evidently more or less flattened by pressure, and whose composition differs some- what from that of the matrix by the presence of some foreign substance which is confined to the fossils themselves, or at least is found in a smaller degree in the surrounding matrix. Such are (a) in the Juras; sic, Chondrites, Theobaldia, probably Discophorites and Gyrophylites, Taonurus (Cancellophycus and Zodphycus), Nulliporites (Chondrites) hechingensis; (b) Chondrites, Taonurus, Caulerpa, Spherococcites, Dis- copharites and Gyrophyllites in the Cretaceous; and (c) in the Tertiary, Chondrites, Caueerpa, Tzenidium, Halymenites, Hormosira, Spherococ- cites, Gyrophyllites, Nulliporites, Aulacophycus, and Taonurus. The author calls especial attention to the fact that these two classes are quite distinct and that there is no transition between them, thus indicating a different origin. Review of Recent Geological Literature. 55 Reviewing Nathorst’s experiments with worms, pebbles, twigs, etc., by which he reproduced so many problematic genera, he shows conclusively that these artificial alge are always found on the lower surface of the strata, never penetrating into the substance of the rock, but always ap- pearing in “demi-relief.” He observes that they possess the precise characters of the first category, a fact of muchimportance. With regard then to so many as fall into this list he agrees with the opinions of Dr. Nathorst, unless it may be concerning Cruziana, whose form is unlike the traces of any known animal. By fossilization in “ demi-relief”’ Mr. Maillard means the natural mould of an impression. It is a bas-relief and like the latter it can only be superficial. After discussing the observations and evidences brought forward by Saparta to show that these demi-reliefs are fossil plants, he insists that if these plants could fossilize in demi-relief, it ought to con- stitute wherever it occurs a generality; and, secondly, that these reliefs should occur on the upper face of the strata since the contrary is at var- iance with the laws of fossilization. On the other hand their presence on the inferior surface proves that, under the probable conditions of de- position, there must have been creases or moulds in the matrix which were filled by sediment, and which were made by a mechanical agent whose nature may or may not have been organic. Accordingly he ex- cludes all those forms in “demi-relief,” which constitute the first cate- gory, from all possibility of vegetable origin. Passing to the second category the author calls attention to the fact that none of the genera in the first ever contain characteristics of the other, and that, while the representatives of the first do not show the least evidence of a chemical or mechanical difference in structure from the matrix, in the other by careful experiment he has never failed to show a difference of composi- tion. To this he has brought further evidence by the use of the micro- scope, showing in many cases the arrangement of the cells as well as a typical dichotomy. It is impossible to give here an outline of the author’s discussion of the occurrence and habitat of fossil Algz, or the conclusions as to the nature and affinities of those problematical species to which he devotes special consideration. Enough has been said to form a suggestive hypothesis for observation. As to the former, he favors the transportation theory ; in the latter he argues that all attempts at a systematic classification are at present futile since not more in fossil than in living alg can species or genera be based merely on form; but that larger series must be used, combining also the study of the cells, the fruits, and the correlation of the organs. Instead of speaking of genera or species of fossil alg, he urges that, except in perhaps the Diatomacez, and those calcareous alge in which the structure is preserved, the use of the word form be adopted. In concluding the memoir he gives five well executed plates illustrating his categorical classification by artificial ““demi-reliefs,” formed by the method employed by Nathorst, as well as by traces of tertiary animals and true fossil alge. 56 Review of Recent Geological Literature. Synopsis of the flora of the Laramie group. By LESTER F.Warp. Pages 399 — 557; plates xxxi—lIxv. (Accompanying the sixth annual report of the director of the U. S. geological survey.) The history of the discussions respecting the age of the Laramie group occupies nearly thirty pages at the beginning of this memoir. Lying between the previously recognized Cretaceous and Eocene systems, its flora is thought by Lesquereux and others to be most allied with the latter, while its fauna is closely related to that of the Cretaceous. With its representation of earlier and later phases respectively of animal and plant life, it supplies a bridge across what had been regarded as one of the greatest breaks in geologic time. The Laramie group is defined as an extensive brackish-water deposit situated on both sides of the Rocky monntains and extending from Mexico far into the British North American territory, having a breadth of hundreds of miles and representing some 4,000 feet thickness of strata. When this deposit was made, its area was an immense inland sea cut off from the ocean by intervening land areas, through which, however, it is believed that one or more outlets existed communicating with the open sea at that time occupying the territory of the lower Mississippi and lower Rio Grande valleys. This Laramie sea existed during an immense period of time and was finally but very gradually drained by the eleva- tion of its bed, through nearly the middle of which longitudinally the Rocky mountains and Black hills now run. The exceeding slowness of this event is shown by the fact, clearly brought out by Dr. C. A. White, that the marine forms of the underlying Fox Hills strata, as they grad- ually found themselves surrounded by a less and less saline medium on the rising of the intervening land area, had time to become trans- formed and adopted to brackish-water existence, while these new-formed brackish-water species, when the sea at length became a chain of fresh- water lakes, had time again to take on the characters necessary to fresh- water life. Remains of the vegetation of the Laramie age occur far more abun- dantly than do those of any of the other forms of life. In its swamps were formed extensive beds of peat, and its wast marshes were densely covered with cane, bamboo, and scouring rush, the thick accumlation’ of which are now preseved in its beds of coal, chiefly lignite. These are usually overlain by strata rich in fossil plant remains, showing that the rate of subsidence had then exceeded that of the growth of the deposit and the shallow sea had gained access, burying the last of the plants under its siliceous or argillaceous precipitations where they are pre- served. In numberless places the profusion of leaves is so great that there is too little rock between them to render it easy or even possible to separate them and obtain complete specimens, The presence of palms, Ficus, Cinnamomum, and other tropical genera in the southern portion of the Laramie area, while its northern portion has many species of Populus, Corylus, Viburnum, and other genera common to cold climates, indicates, as the author believes, a greater Review of Recent Geological Literature. 57 difference of climate than can be accounted for by the difference of latitude. In explanation of this it is suggested that the nearness of the ocean on both the east and west sides of the southern portion of the Laramie area probably contributed much toward producing its equable and moist climate, nearly or altogether free from frosts. Farther north there is evidence that the Laramie period included a change from a warm to a comparatively cold climate. All the species of plants that had been authentically described and re- corded up to the date of this memoir in the Laramie group, in the Seno- nian of the upper Cretaceous, and in the Eocene, are enumerated for comparison in a very elaborate table, which fills more than seventy pages, including 1,540 species, of which 1,254 are phenogams. Among the phenogamous genera in the Laramie group are Sequoia, represented by six species; Taxodium, three species; Thuya, two; Sabal, four, and thirteen other species of the palm family; Populus, twenty-three; Salix, three; Quercus, twenty-three; Corylus, five, including the two species now living in the northern United States and Canada; Alnus, two; Betula, three; Juglans, eight; Platanus, eight; Ficus, twenty; Laurus, six; Cinnamomum, four; Cornus, four; Aralia, four; Rhus, five; Acer, three; Sapindus, four; Vitis, five; Rhamnus, twelve; Nelumbium, two; Magnolia, six; Fraxinus, two; Diospyros, four; and Viburnum, fifteen species. In total the Laramie flora enumerated in this table comprises 323 species, of which 275 are phenogams, 226 being dicotyledons. The author remarks that the flora of the Laramie group furnishes evidence of having descended more or less directly from that of the Cre- taceous of this continent, and that in many cases the lines of descent can be traced through the upper or Senonian beds to those of the Dakota group or American Cenomanian. The diversity of floras now existing upon the earth’s surface has its analogue in the diverse but at least ap- proximately contemporaneous floras of past periods through the Tertiary and Mesozoic eras, but in gradually diminishing degree, until in the Carboniferous period a nearly uniform flora overspread the entire globe. But much of the present extraordinary variety in the floras of different countries is attributable to the special agency of the successive glacial epochs which have occurred since Tertiary time, driving the floras south- ward and out on the southern plains to be destroyed on the return of warmer climatic influences or compelled to intrench themselves upon the summits of the mountain ranges, while new and constantly varying forms became developed to take their places in the lowlands. After extensive detailed comparisons of the species tabulated, the au- thor decides that the Laramie flora as closely resembles the Senonian as it does either the Eocene or the Miocene. Portions of Mr. Ward’s collections of Laramie plants, made in 1881 and 1883, were illustrated in the plates accompanying this memoir, which present eighty-four new species, not contained in his table, with fifty-six that were before known. The localities of their collection are briefly noted, but their descriptions and critical comments upon them were not 58 ‘Review of Recent Geologica: Literature. then in readiness for publication; and these have since been supplied in Bulletin No. 37 of the U.S. geological survey, entitled Zyfes of the Lar- amie flora, containing 115 pages and 57 plates, on which the same figures are reproduced. Both these reports are preliminary to the author’s forthcoming monograph. Among the new species the genus Populus claims ten; Quercus, two; Corylus and Alnus, each one; Betula, two; Platanus, one; Ficus, five; Ulmus, four, all from asingle locality in Mon- tana, being the first record of this genus inthe Laramie flora; Vitis, four; Celastrus, seven, again constituting the first Laramie record of the genus; Grewiopsis, five, only two species having been previously recorded in the Laramie; Pterospermites, three, its first Laramie record; Cocculus, Lir- iodendron, Magnolia, and Diospyros, each one; and Viburnum, ten. Only two of these genera,.namely, Grewiopsis and Pterospermites, have become extinct. The similarity of the early types of phenogamous plants with those of the present time is well shown by their occurrence in the Laramie flora, including the author’s table and his later additions, of seventy-four phen- ogamous genera thatare still living, while only twenty-two have perished, nine of these last indeed being scarcely distinguishable from their present generic representatives in the living flora. Not somany asa half dozen phenogamous species, however, have come down to us from the Laramie period, nor in total from the Eocene, Laramie, and Senonian floras. Four, all belonging to the Laramie, are so recorded. These are well known species of our northern temperate flora and limited to North America, namely, the two common species of hazel-nut, the butternut, and Vibur- num pubescens, Pursh. On an Archean plant from the white crystalline limestone of Sussex county, NG.) By DR. BRITTON. (Annals, N.Y), Acad.Sciences, vol.iiv iene ruary, 1888, pp. 123—124, pl. vI1.) In one of the detached areas of the white crystalline limestone in Sus- sex county N.J., Dr. Britton has found black filmy bands of graphite parallel to the bedding of the limestone. These bands reaching in some cases a thickness of 0.5 mm. and measuring about 3 mm. in width, are found in broken fragments averaging about 6 cm, in length, apparently having formed matted patches which are now transformed to thin strata ofcarbon. Though it seems probable that mineralogists as well as paleo- botanists will question its vegetable nature, and protest against its addi- tion to the already large number of problematical organisms, still, what- ever its ultimate fate may be, it enjoys today the distinction of being the the oldest impression that has yet been referred to the vegetable kingdom, Without attempting to indicate a more definite affinity than its probable relation to the Algz, Dr. Britton has figured and named this new species, in honor of Dr. Newberry, as Archeophyton newberryanum. Geological Survey of Ohio, Vol. VI, Economic Geology. EDWARD ORTON, state geologist. The bulk of this volume is devoted to petroleum and natural gas, with vaiuable chapters on salt, bromine, cement, gypsum, lime etc., To the Review of Recent Geologicai Literature. 59 ‘citizens of Ohio, looking for practical information and tangible results these economic investigations will possess the greatest interest and value; but to the Grotoeist at large, the first chapter, “The Geology of Ohio Considered in its Relations to Petroleum and Natural Gas,” will sound the key note and absorb most attention. Prof. Orton has made considerable changes in the geological column as previously published in the Ohio Reports. Following is a table of Newberry’s arrangement (Ohio reports, 1 88) set side by side, for easy comparison, with Orton’s present arrangement. NEWBERRY. ORTON. Upper Coal Measures, Upper Barren Coal Measures. #4 | Barren Measures. Upper Productive Coal Measures. = Lower Coal Measures, Lower Barren Coal Measures. = | Conglomerate. Lower Productive Coal Measures. = | Lower Carboniferous limestone. Conglomerate. a Cuyahoga shale. Sub-carboniferous limestone, 2 Shale. 5 Waverly ....{ Berea grit. Logan..4{ Sandstone. 6) Bedford shale. | Conglomerate. Cleveland shale. Waverly? Cuyahoga shale, Berea shale. Berea grit. - | Erie shale Bedford shale. P| > .s | Huron shale. Bienes fSandusky 1 Cleveland shal ‘ andusky limestone. eveland shale. 5 Corniferous... (Columbus limestone. Ohio shale Erie shale. A | Oriskany sandstone, Huron shale, Hamilton shale. Devonian limestones. F Helderberg—Waterlime. a Salina ae = Lower Helderberg limestone. A Hillsboro sandstone, : 2 ; Niagara sandstone. Hillsboro sandstone. m | Niagara, - 73 Guelph sandstone. : Niagara shale. Niagara...) ni. if t 4 Dayton stone. Niagara limestone, & Niagara shale—Dayton stone. = ee Clinton. 2 : Medina. 5 Lebanon beds, Hudson River series. % | Cincinnati group 4, Eden shales. Utica shales. ; Point Pleasant beds.| Trenton limestone. Beginning at the bottom the first change we observe is the omission of the Cincinnati group, a term so familiar in the geology of the great interior of North America that its absence occasions a slight pang. It was used by Meek and Worthen to designate the western equivalents of the Hudson and Utica shales; and Newberry added the Point Pleasant beds which belong to the Trenton. Orton finds the Utica shales absent at Cincinnati; though they prevail widely in northern Ohio, as shown by the numerous deep borings for gas and oil, and, relegating the Point Pleasant beds to the Trenton, the remaining element of the Cincinnati group is simply the Hudson river shales. The Cincinnati group is there- fore dropped as being synonymous with Hudson, which has the priority. The only weak point in this reasoning is that the Utica may not be 60 Review of Recent Geological Literature. wanting at Cincinnati. Its absence is affirmed by Orton upon lithological grounds, but Ulrich maintains upon paleontological grounds that it is present.! Next we note the omission of the Salina group. It was introduced by Newberry on the supposition that the gypsum beds near Sandusky were between the Waterlime and Niagara. Orton finds them to be “buried in the middle, or above the middle” of the Waterlime. In New York gypsum is found in a similar position in the Salina. Next comes the omission of the Oriskany, which never had a secure footing in Ohio geology. A more radical change appears in placing the Cleveland shale in the Devonian instead of the Carboniferous, and massing it with the subjacent Erie and Huron shales, giving to the whole the name Ohio shale. All this seems to be in the interest of simplicity and accuracy, since the former reference of the Cleveland shale to the Carboniferous was due to its correlation with the Waverly Black shale, designated in the above table as Berea shale. The addition of this Berea shale is the next change; and the last one of any importance; the introduction of the Logan group, is also an ad- dition. : Most of the changes are omissions, and they are commendable as tending to simplify the Ohio column, and to render its correlations with other states more obvious. About the propriety of these additions there is more doubt. Newberry gave the name Cuyahoga shale to all that part of the Waverly above the Berea grit. The right of priority may be invoked in protest against setting aside, or largely subtracting from, the term as thus defined. It would be more just to the author of that term, as well as more simple and lucid, to retain it with all its original breadth using Berea shales and Logan shales, sandstones, and conglom- erates merely as descriptive subdivisions. Newberry was perfectly aware of the existence of the Berea shale, and deliberately included it in his Cuyahoga shale. (Ohio reports 11 88). He also indicated varying lithological phases of the upper strata of his. Cuyahoga, (Ohio reports, 11 87) and since there is absolutely no paleon- tological distinction between the Cuyhoga and the so-called Logan, the presence of a conglomerate not distinctly indicated in Newberry’s defini- tion of the Cuyahoga does not render that definition so defective as to justify the complication of new names within the interval originally covered by the term Cuyahoga. Prof. Orton announces important results in structural geology. The Cincinnati anticlinal trends northwest instead of northeast. Some of the sharpest foldings in the state occur in the Northwestern counties, where the level surface and heavy cover of drift prevented any suspicion of their existence. Orton is a strenuous advocate of the theory that these disturbances are essential to oil and gas production. 1 See this Journal, May, 1888, p. 315. Correspondence. 61 Beginning at page 96 in Chap. 11, we find a valuable discussion of “rock pressure of gas.” Orton rejects the theory that this pressure is due to expansive force of the gas; also the theory that itis due to the weight of the superincumbent rocks; and thinks the true cause is hydrostatic pressure of subterranean waters, the same cause which pro- duces artesian wells. Chap. 111, on the Trenton limestone will set prospectors everywhere to inquiring, “How far must we go to reach the Trenton?” But even if they reach it the search will generally be in vain, for Orton shows con- clusively, by numerous analyses, that the Trenton is a gas or oil rock only when it has the composition of dolomite. Chap. IV on the Berea grit is of greater interest to the geologist than to the oil operator, since the latter does not find much encouragement from this horizon. The extent and continuity of the Berea, as shown ‘on the map p. 313, are truly surprising for so thin a stratum. “The Ohio Shale as a Source of Gas” is the subject of Chap. V. This stratum is probably the richest in the state, the amount of oil per square mile having been estimated at 10,000,000 bbls., notwithstanding it is practically of little value as an oil and gas rock. Low-pressure gas is obtained from it in many places, but no great wells. Chap. IX on measurement of gas wells, by Prof. T. W. Robinson is a valuable contribution to knowledge. Chap., XIII, “Natural and Artificial Cements” by Prof. N. W. Lord is interesting and valuable, equally to the scientist and the practical man. Chap. XV, by Edward Orton, brings out much new matter in regard to the production of lime, an industry which has been well nigh revolu- tionized by the introduction of natural gas. Many other portions of this work equally worthy of commendation must be passed without mention for lack of space. A careful persual of this volume will convince every one that the royal opportunities afforded to the geologist by the immense number of wells put down in search for gas and oil since the opening of the Find- lay field, have been wisely used, and the interests of our science are there in able hands. CORRESPONDENCE. The Huronian of Canada. On page 238 of the AMERICAN GEOLOGIST (vol .I, No. 4,) Mr.S. A. Miller refers to Alexander Murray and the “ Hu- ronian series,” and says: “If he had read Emmon’s Zaconic System it is difficult to conceive why he should have hesitated in referring the rocks to that system;’ and Mr. Miller further says: “The word Huronian is therefore a synonym for Taconic.” I think Mr. Miller would scarcely have made such a statement had he 62 Correspondence. ever studied what we know as Huronian rocks in Canada, and which owing to the often impossibility of separating them from the Laurentian, we have latterly included under the name pre-Cambrian. The Huronian of Canada is, so far as we know, wholly unfossiliferous, and largely metamorphic, and is unconformably overlain by rocks of lower Cambrian age. Now I have heard a great deal about the Taconic system but have never used the name, being unable to make out precisely what it was. Recently, however, Mr. Marcou has defined his view of the Taconic,} which appears to be very different from that of Mr. Miller, while Pro- fessor Walcott seems to regard it in very much the same light as I have been obliged to regard the “Quebec group,” and I may say that I fully concur in Mr. Walcott’s views. Some of Mr. Marcou’s Taconic near Quebec is certainly newer than Trenton limestone while Mr. Miller’s Taconic commences below the Potsdam. These wide differences of opinion as to what Taconic really is are, I think, a strong argument in favor of adopting Professor Walcott’s views on the “Use of the name Taconic,” as expressed in the American Journal of Science, May, 1888. ALFRED R. C. SELWYN. Ottawa, Fune 1, 1888. Lake beaches at Ann Arbor. Dr. Wooldridge and I have gone over the beaches in the region of Ann Arbor. I fully concur with him that the Ann Arbor terrace is one of construction at the mouth of the Huron River (of that time) which now bends abruptly there. In short it is rather a terrace delta deposit between clay islands; and the cut terrace plain below, or the old lake bottom extends for some miles. Yours, etc., J. W. SPENCER. Dr. Wm. Clark of Berea, O., has been continuing his enthusiastic and successful researches in the Ohio shale and has now the most remarka- ble collection of fossil fish (?) that has perhaps ever been brought together in America. He is already known to paleontologists as the discoverer of the huge fossil described by Dr. J. S. Newberry at the meeting of the B. A. A. S. at Montreal, in 1884, and on which in honor of the finder was placed the name 7Zitanichthys clarki. This measures about fifty-six inches across the head-shield and was the largest relic of a so-called fish that had, up to that date, been obtained from any part of the world. But the labors of 1886 and 1887 have been rewarded by other specimens of parts of this monster —a second head-shield surpassing the first and measur- ing Seventy-one inches in breadth by 69 inches in length—a mandible thirty-five inches long with perfect alviolar process and groove —a pair of mandibles, right and left, thirty-four inches long by five inches deep —a fourth nearly perfect and thirty-one inches in length — and the an- terior portion of a fifth, twenty inches long carrying a perfect tooth, and the base of a second in the socket. To these we must adda large median 1 Memo. of the Boston Soc. of Nat. Hist., vol. iv, March, 1888. Correspondence 63 and two lateral dorsal plates of the same species of Yvracostens clarki. There are two mandibles set with teeth in position close and sharp, round in section, smooth, and about one-eight ofaninchlong. The head-shield shows the orbits, four inches in diameter, complete. There are also fragments of a second with the head bones separate and four tubercular plates, each tubercle of which ends in a spinous point. The upper pre- maxillary, part of which only is present, ends in two hooklike teeth. The largest tuberculated plate measures seven inches by nine, and the specimen is about fifteen inches over all in width. The most remarka- ble “find,” however, of 1887, consists of two fossils so different from any- thing yet known as apparently to be the types ofa new family. The first of these has a very elongated narrow body, resembling that of a gar-pike in general form. The snout is sharp, with a projecting tip and narrow, with long slender jaw bones, set with minute teeth of cladodont type, but very small. The front of the mandible is furnished with a large cutting tooth. The body was covered with very narrow, lozenge-shaped ganoid scales. Only two fins are present, set well forward, behind the head, with rounded ends and very strong rays. This specimen measures seven inches from tip to tip of these rays. Posteriorly, the body which is about twenty inches long tapers slightly with indications of a small caudal fin, but the actual end has not been preserved. The second fossil is broader and shorter, with heavier jaws, stronger, coarser, and more numerous fin-rays, and measures eight inches over the two fins, by twenty-four inches in length. It shows some signs of an ossified spinal column. The ganoid scales have projecting points which fit into grooves in those adjoining them. Of this form there are several specimens, showing the head and fins. The range in size of the species, is shown by one of these, which measures twenty-four inches across the fins, each of which is nine incheslong. The hinder end, which is well preserved, apparently terminates in an expanded and laterally flattened tail (as the flukes of the whale), showing some indication of a caudal fin. Dr. Clark has also obtained two crania of a Dinichthys, apparently new, and four mandibles, (one nearly perfect,) two premaxillary teeth five inches long, and four lateral or cutting teeth four and a half inches long; a pair of ventral plates, a pair of clavicles(?), a pair of unknown bones found with the rest, and a large number of plates, probably belong- ing to D. Tirelli or to D. Herzeri, some of which have been entirely un- known hitherto. In the same collection is a new (?) placoderm with mandible about twenty inches long and dofsal plates measuring nine inches by seven, having a very short crest and no neck, thus differing from those of Dinichthys. All the above were found in the Cleveland shale of the Ohio Geological Survey. Those yet to be mentioned came from the Cuyahoga shale and are (1) a fossil about two and a half feet long, the jaws of which show cladodont teeth, but this, if not new, has not yet been identified. (2.) A 64 Correspondence. number of large, flat, pavement teeth of type hitherto unrecognized, and (3) a nnmber of slabs showing teeth and finrays of cladodont fish. (4) A Ctenacanthus spine, associated with dermal ossicles; (5) coprolites, and (6) some nearly entire and one entire paleoniscoid fish. All these are from the black base of the Cuyahoga shale (Berea shale of Orton) a bed that has hitherto yielded little besides Liagula and Discina. E. W. CLAYPOLE. Cleveland, Ohio, May 15, 1888. Mr. J. S. Diller of the U.S. geological survey has kindly sent to me, for comparison with the Nebraska deposits described by Prof. Aughey, the following specimens: Slide No. 1.— Volcanic dust from the eruption of Krakatoa, collected on Italian man-of-war Adriatico, 200 miles south of Java. Slide No. 2.— Dust collected by Prof.J. E. Todd, Knox Co., Neb. Slide No. 3.— Dust collected by Prof. J. E. Todd, Seward Co., Neb. Slide No. 4.— Dust collected by Col. Sizer, Phillips Co., Kas. Slide No. 5 Dust collected by J. A. Udden, Lindsberg, Kas. I find no important constant difference between the undoubted volcanic ‘dust and the other slides 2, 3, 4, and 5. No.1 is somewhat finer and con- tains more granular and fibrous particles mingled with the thin flakes which constitute the unique feature of all the specimens. An important point of resemblance is that these flakes, although so thin, have azr-bubblesinclosedin them. These are spherical, oval, spindle- shaped, narrowly elongated, X&c. I found them in all but the Lindsberg specimen. Nos. 3 and 5 contain diatoms. The presence of air-bubbles favors the theory of volcanicorigin. How- ever, I regard the question of origin as not absolutely settled until the stratigraphy of this dust stratum and the associated strata has been thoroughly worked out in the field. This stratum may prove to bean important datum plane for the correlation of other strata. IDE IA Ve hier | 8 SS ; s a 5 oOo 8 = Be ea Sas One ae i yess | s = ne Der Se ea & Ee Ol ie Sf.) 5 coc™ 2 z nB Be wo! "20p & ¢ S38 OAR is i“ o> e327 © oon Soe B BS see 5 SS, SSS ae o & BEN ones 9 sed 4.8 of one Ses o 8 s¢ | re) a ah S Pi Die Berane SNe Tn 2 8 (oF rm 6 oe © os = Aes! On e Sey ae a = es) aS on We = e: a, Sam asian yds Ip SRP oon Ska as Hh? [vie] _ : 0g Bs iat f dX fm on iS) SS Sl= é = Ae 5 EE & e A 2 SOP q QsH HH a2 2 | ops & Bio gf so © | SSSh 5 Bos & #4 B | Bao, 2 ono 2 of oF Las Ret O * 4 8 Roh Sp ia See Us! ee er se oem rh (2 Soli es Bot & Bi Sse & eet atta a Rois & Sie tee wh PRoere ales pe fe) Sizes 5 5 EDN Saige Ses Sp ES mn Q wn wa | DESEOSES =) Qe. S Be PRESSE OSES Rote Shp s ton, ms Cpt npPatCGpes — Wee oe SSS © Oey eo eDePn. 2 =| Som EE?) BSE = 8 Sie; cf = = | -BpSSSnaee ate moe Epe ease p Ss ria) hip aenc ee lho ar egre SSE 86 7 S 0 Besta” pea = ot ce sor oPsngo v eS mS ES e ho © Cie ecOoost Ba Ss poche] ge | ete Gorm ei ty Poe? ge & raat 0 aL ele) ht 1 re 87 ‘NWOLSAS OINOOVL HHL JO MAIA YING 38 North American Eastern Tertiary — Meyer. at years ago by Emmons, Barrande and Marcou. Only in re- gard to Emmons he pretends that “it was a_fortunate happen- éng,;” as to Barrande he was, according to Walcott, misled in crediting Dr. Emmons; and as to Marcou, Mr. Walcott passes silently over him. Here is a tabular view showing the opinions and classifica- tions of Messrs. Walcott and Marcou in the Taconic area ex- tending from Tappan sea to Montmorency Falls. MR. WALCOTT. INOS ir. G4 GEO SOM es ccd eo ee en cen ee RN SER a pee \ Lower Silurian, or No, 3—Trenton-Chazy-Caleiferous.....:.....ccsc.cevesceisesscssscsssceoscascoes sf Ordovician system. TAO WET! Call CHONOUS Bun. acisusacs css tuaase nn metwecdencwo ero tks hocaee opae ee ec aseeaae 1 1 = No, 2—Potsdam, ‘‘ Off-Shore GPOSIts’’.........csccesecescccecsevcessccnsceacees J Upper Cambrian. Nos. 5 and 1—Georgia and ‘‘granular quartz’’ formations of ) Upper part of the VERNON res wte couse cntaesee a ee teah eanine goauioustass shMaue ee ecmat cecett Secenrie a f Middle Cambrian, orraime (Shales: s70, ees ON see eae L cL were MANO a eae Or | LU EES WAFS) FE WTF ae Re A a ea ES a a * ate EEPEN TON WILIMESTOMOs rau, sche chee cesarean oese a ce Seat ence ceed Ren hs Pope ert ean Chazys limestone. sci haecasse oes rena ieen oem ene ee aoe eee eee | viBieN IVa CiTErOUS!SANASHOME hse. ae UC ee fata ete eaten ONO a ete hl M sUpper Potsdam of Saratoga................s.cbee0- ) Potsdam sandstone... (Lower Potsdam of Keeseville...............c0ceec00+ Swanton slates and shales of Citadel Hill, Quebec. The Nos. 6 and\| Upper Taconic ASOT) MPs Wil CObE eS eee Oe Aes AOR DAD AC AL VENDA EN Dane system. . Phillipsburgh and Pointe Levis formation. The No. 3 of Mr. Wal- cott, and also his No..2 ‘‘ off-shore GepOSsits’’............ccccccssecaseenees {Georgia slates. The No. 5 of Mr. Walcott...... | Upper part of the Georgia formation; St, Albans or granular quartz. The No. 1 of} Middle ( ME SSWiall C OCG? cos ctercoed Soroka eco ncens setae bee cbeee | Taconic system. SOME REMARKS ON THE PRESENT STATE OF OUR KNOWLEDGE OF THE NORTH AMERICAN EASTERN TERTIARY. BY OTTO MEYER, PH.'D, The marine Tertiary of the eastern part of the United States is extensively developed in all the states along the coast from New York to Texas. Along the Mississippi valley it pene- trates deeply into the continent, reaching into the states of Ar- kansas, Tennessee and Kentucky. It thus covers a large area and is altogether one of the most extended tracts of marine Tertiary on the earth, in comparison with which the famous North American Eastern Tertiary — Meyer. 89 ‘Tertiary territories, like the Paris, London or Mayence basins, are insignificant spots. Owing to the small amount of work done in this large field this formation is comparatively unknown. While the states whose territory is constituted by older forma- tions are mostly well studied and mapped. The Tertiary states, if this expression may be used here, stand generally in these respects behind some western territories. The eastern Tertiary may be divided into two groups; one, the Atlantic group, comprising the Atlantic states proper from New Jersey to Florida, the other, the Gulf group, including the states from Alabama to Texas. In the first group the younger Tertiary formations are extensively developed, while the marine beds of the Gulf group are Old-Tertiary. We may consider first this Gulf group. Tue Guir Group—Our knowledge of the paleontological condition of the Gulf group is unsatisfactory. There are in- deed several hundreds of species of marine invertebrates known from it, in the description of which quite a number of authors have participated —S.G. Morton, T. A. Conrad, I. Lea, H. C. Lea, W. M. Gabb, R. P. Whitfield, A. Heilprin,O. Meyer, T. H. Aldrich, D. W. Langdon, H. B. Geinitz. Yet there is no doubt that many hundreds more occur in it, which are still unknown. Almost every new locality furnishes new species, and the most thoroughly explored places yield new forms, when again examined. It is, however, less the quantity of known paleontological material, which is unsatisfactory, than the quality, and the writer, after having examined nearly all the existing type-specimens of the Old-Tertiary may be pardoned, when he calls this part of science an Augean stable. At present, however, thanks to the energy and liberality of Mr. T. H. Aldrich, there is sufficient reason to expect, that the paleontolgy of the eastern Old-Tertiary will be soon thoroughly worked up. Our knowledge of the stratigraphy of the Gulf Tertiary is still worse, inasmuch as the first foundations of it are uncer- tain. The marine Tertiary occupies a territory extending nearly parallel to the gulf of Mexico through Alabama, Mississippi, Louisiana and Texas. In the last three states and apparently also in western Alabama this Tertiary is separated from the gulf by a formation composed of sandstones, massive clays, etc., Xe) North American Eastern Tertiary —Meyer. and designated as the Grand Gulf formation. The relation of . this Grand Gulf to the Tertiary affords the following two pos- sibilities. [1.] The Grand Gulf formation is younger than the marine Tertiary north of it and overlaps it. [2.] The Grand Gulf is older than the marine Tertiary and underlies it. In connection herewith stands the stratification of the marine Tertiary itself. In the first, case all the strata in general would slope down towards the gulf; inthe second case the stratifica- tion of the Tertiary would be that of a trough. We may con- sider a special case. It is generally accepted that Vicksburgian strata occur south of Jackson, Miss. In the first case apparently these strata would be younger; in the second case we may con- clude them to be older than the Jackson beds. It must not be overlooked, however, that if the Grand Gulf is older than the Tertiary, we have to expect a trough shape of the Tertiary only there, where the Grand Gulf exists. In eastern Alabama where no Grand Gulf is known to occur, a trough shaped stratification of the Tertiary can hardly be anticipated in any case. From the foregoing we see that the foundation of the strati- graphy of the Gulf states is the relation of the Grand Gulf to the Tertiary. Until a few years ago, when the writer disputed the validity of the existing theories, geologists did not think of the possibility of the Grand Gulf being older than the Tertiary, as the contrary was considered to be proved beyond a doubt by Hilgard. And only at a recent date Hilgard again repeated the statement, that the Grand Gulf sandstone is found overlying the Vicksburg strata, “as verified innumerable times.” [ Science, Jan., 1886, p. 11.] But as for this I can only repeat, that I have been unable to find in the whole known literature a single place described, where the Grand Gulf strata can be seen in di- rect superposition to the Tertiary. I would therefore, urgently request any one who has information of it to give me a single locality where the Grand Gulf can be seen actually overlying the Tertiary. Although I found a number of interesting objects in Mississ- ippi, I was not successful in finding a contact of the two for- mations. I described two localities where strata, which look like Grand Gulf strata are overlaid by marine Tertiary, but unfortunately they only have this appearance, and it cannot be North American Eastern Tertiary—Mevyer. gt said that they are Grand Gulf, For the question is made more complicated by the difficulty of determining what are Grand! Gulf strata. Mr. Aldrich and myself met cross-bedded lignitic strata without fossils, south of Terry, Miss., which we considered as Grand Gulf. In beds near Brandon, Miss., which look very much alike and which are overlaid by orbitoidic limestone, we found impressions of marine shells. In the typical locality, the bluff near the town of Grand Gulf, I found impressions of sev- eral species of Unio. Therefore if the Grand Gulf formation is entirely a fresh water formation, the lignitic sands near Bran-. don do not belong to it, but it seems arbitrary to consider the sands near Terry as Grand Gulf. In the Grand Gulf bluff I did not notice such lignitic sands. If the synclinal form of the Tertiary should be proved, these lignitic strata may be consid-. ered identifiable with the more northern lignitic beds in Mississ-- ippi. The only rock that may with some certainty be regarded as. Grand Gulf is the characteristic white sandstone, which occurs in Grand Gulf itself and in many other places, and which is not known in the marine Tertiary. In looking out for a contact of marine Tertiary and Grand Gulf therefore we ought to search for a point where the white sandstone is in juxtaposition with the marine Tertiary. Such a contact might be looked for with some expectation of success in Louisiana at the Washita river. Hilgard says, Am. Jour. Sc., Nov. 1869, p. 339: ‘According to the observations of my companion, Dr. Walker, who de- termined the line between this [ the Vicksburg group ] and the Grand Gulf group on the Washita, lumps of Orbitoides lime- stone at the foot of Grand Gulf sandstone ridges are the first evidence of the change of the formation.” . From the foregoing it appears that one of the foundations of southern geology, the relation of Tertiary and Grand Gulf, must be considered as yet undecided and in connection with it the succession of most of the Tertiary strata remains to be cleared up. Some European geologists seem to understand that I consider the former succession of strata as Jroved to be reversed, but I think this point undecided, although indeeed it seems to me more probable that the Grand Gulf will prove to be older than the Tertiary. Against this supposition the following ob- 92 North American Eastern Tertiary — Meyer. jection is usually raised. If we look at a geological map of the U. S., we see that we come from older -formations to younger ‘ones, When we go from the interior towards the gulf of Mexico; we pass paleozoic, older mesozoic, Cretaceous and Tertiary formations and finally the Grand Gulf; the nearest to the Gulf, must be the youngest one, evidently all formations slope down- wards towards the gulf. This observation, however, does not ‘invalidate the assumption, that the Grand Gulf existed as an island or a peninsula at the time when the Old-Tertiary deposits were formed. If we suppose that all the formations in un- broken succession were deposited in the gulf and gradually up- lifted in the way the above objection assumes, then we ought to have the following succession: 1, marine mesozoic forma- tions; 2, marine Old-Tertiary; 3, marine Miocene; 4, marine Pliocene or post-Pliocene; a succession’ which may be found on the Atlantic coast. In place of No. 3, we have now the Grand Gulf formation. This is not marine and is unlike the Tertiary north of it. If there was nothing but a continuous deposition in the gulf, and an uplifting afterwards in concentric formations why was the process of forming sands, clays and limestones teeming with marine shells suddenly interrupted at the end of the Old-Tertiary period? And why were thick strata of sandstones, massive clays etc., deposited, in which not a single marine shell, but as yet only a few fresh water shells have been found? From the former general point of view I cannot find any real explanation, and those explanations which have been ventured [before the presence of fresh- water shells was known] need only be cited’ to create a sus- picion that there must be a mistake somewhere. We have thus very little knowledge of the stratigraphy of the Tertiary in Texas, Louisiana and Mississippi. In Alabama, however, the Geological Survey under Prof. E. A. Smith, has brought to light many facts, the main substance of which has been published in the Bulletin I of that survey. The possibility of error in this field is so large that one or more mistakes may have been committed in the work of the survey, but in general one cannot fail to see the great care which has been exercised 1 See Am. Journ. Sc., Dec., 1885, 12th, and 13th, pages of article. North American Eastern Tertiary —Meyer. 93 -and the earnest endeavor to adhere to facts and avoid specula- tions. A clearing up of the relation of the Tertiary to the Grand Gulf seems not to have been attempted. The Grand Gulf is supposed to occur in the southwestern part of the state, but it is doubtful whether a contact can be found there. It is to be noticed here that the survey apparently has shown, that the “white limestone” is younger than the Claibornian beds. This “white limestone” is considered usually identical with the limestone at Vicksburg, Miss., and this would tend to show that the Vicksburgian beds are younger than the Claibornian, there- fore younger than the intermediate Jacksonian strata; and hence it would be an argument against a synclinal of the Mississippi Tertiary and further conclusive against the greater age of the Grand Gulf. These conclusions, however, contain some weak points, one of them being the identity of the two limestones, separated by so long a distance. It is of little use, however, to discuss this matter more extensively, in consideration of the fact that the direct contact of Grand Gulf and Tertiary has to be looked for and has to be determined beyond a doubt, and that nothing but this will contribute towards adecision of the question. Tue ATLANTIC Group.— The division of the Atlantic group from New Jersey to Florida, comprising mostly younger Ter- tiary strata has been attempted mainly by Prof. A. Heilprin, and a diagram explaining his views may be found in “explora- tions on the West coast of Florida,” p. 127. So far as I have gone in my effort to work out this part of the Tertiary I have been unable to find that his classification and determinations have been proved. The subdivisions of the Miocene seem to me hypothetical and their arrangement in parallelism with European subdivisions like the “First and Second Mediterranean” in Austria which are themselves stongly attacked, seems to be still more hypothetical. The orbitoidic limestone in northern Florida is with positiveness placed on the horizon of the beds of Vicksburg, Miss. Those specimens of rock which I have ‘seen contain Orbitoides in a species which is not shown to be the Vicksburg species, and probably is different from it; and ‘contain besides a Pecten, which is entirely different from the Vicksburg Pecten poulsoni Morton, but which apparently agrees with the Jackson Pecten. These rocks therefore have 94 Geology of the Montmorenci— Emmons. not been shown to contain one species which occurs in Vicks-- burg. Ifa parallelism with a Mississippi bed was a matter of necessity, one might have thought of Jackson, where a species. of Orbitoides, and the Pecten occur; but I think that in the present state of our knowledge any parallelism like that does not rest upon sufficient evidence, and cannot claim to be more than a vague hypothesis. Moreover, on account of this paral- lelism with the beds of Vicksburg, Miss., Prof. Heilprin calls. these and other rocks, which contain nummulites etc., Ol- igocene. Iam aware of no fact that proves that the Vicksburg beds are contemporaneous with those of the typical European Oligocene. On the contrary, the position of these beds in their: original state appears to be very doubtful. Now, to take one example, it will be extremely difficult or impossible for any geologist to prove, that the north Floridian limestones or the beds of Vicksburg in Mississippi were 7zo¢ deposited at the same time as the German Rupelthon ;but on the other hand it cannot be wondered at that such hypotheses are considered mere guesses. The paleontology of the Miocene is in nearly the same con-- dition as that of the Eocene. As a subdivision of the Miocene will mainly be based upon the examination of its fossils the first desideratum would be an investigation and good representation. of the Miocene fossils. Until this is done a subdivision can: hardly be undertaken with any expectation of approaching ac-- curacy. GEOLOGY OF THE MONTMORENCI. BY EBENZER EMMONS, M. D, [rom the American Magazine, November, 1847.| The fall of the Montmorenci, in whatever light it is viewed, is an ob- ject of great interest. Hitherto it has been mostly regarded as an interesting spectacle, mag- nificent phenomenon, and so it truly is; but leave out of view those striking features which impress the beholder with awe and admiration,, still it is well worthy the attention of the traveller and tourist. I propose therefore, to give a brief aecount of those points and features: which I found interesting, on a recent tour of observation to this cele~ Geology of the Montmorenci—Emmons. 95 ‘brated spot; more particularly, however, of the geological structure of ‘the fall, and of its immediate vicinity. The river Montmorenci flows from the mountain woodlands, in a southerly direction, and joins the St. Lawrence seven miles below Quebec. The fall is sixty or seventy rods above the junction of the two rivers, and for this distance it is a deep gorge, with perpendicular sides, which has been formed by the river. The amount of the fall is said to be two hundred and forty feet, though to most observers it appears something less, which is doubtless owing to the great width of perpen- dicular rock over which the river is precipitated. The water in its descent appears like a broad sheet of white foam, which, contrasted with the dark walls through which the river has cut its way, adds greatly to the beauty and magnificence of the scene, and serves to arrest at once the attention of the observer, and fix him in an attitude of profound awe and astonishment. Leaving at this point all details in relation to the geography of the river and its scenery, we pass to the consideration of the geology of its vicinity, and especially of the fall, which, as I have already said, is a spot of great interest, and to the scientific tourist fur- nishes some facts which will serve to elucidate the structure of the sur- rounding region, which otherwise would be quite obscure, or at best conjectural. The tourist will generally take his departure fora visit to the fall from Quebec. His route, after passing the bridge over the St. Charles is on the Beauport road, the direction of which is indicated by a long row of neat white cottages, which form the village of the same name. Adjacent to the St. Charles, the country is mostly level, and presents fertile and well cultivated meadows and farms, and for two or two and a half miles no rock appears from which the geology of the district can be determined. The formation at Quebec, as is well known, is the gray- wacke of authors, consisting of schistose strata, argillaceous slates, thin bedded sandstones, fine and coarse breccias, of a green color, and inter- laminated with a shaly bituminous limestone, in a highly inclined position. ‘This rock is lost sight of at the lower part of the city, and disappears at once, and we pass from a high, prominent, rocky ridge to a level and smooth country, apparently undisturbed by any uplifts or other derange- ments. On reaching the Beauport river at the southern extremity of the vil- lage, the rock which underlies this section of country appears for the first time; it is a black limestone, regularly bedded and nearly horizontal, presenting a remarkable contrast with the highly inclined rocks of Quebec. This limestone does not appear entirely alone, for at a few points a black slate projects above the surface, and occupies a position on the same level as the limestone, against which it apparently rests. This association of rocks, taken in connection with their position, in- dicates some derangement; and a close examination would undoubtedly result in the discovery of an extensive fault, or uplift, along the line which the road passes. 96 Geology of the Montmorenci— Emmons. To be more particular as it regards the designation of rocks, I remark, that the first is very clearly the Trenton limestone, so frequently spoken of in the New York Geological Reports, containing abundance of the Strophomena alternata, and Orthis testudinaria, together with many other fossils, which are known to occur in this rock at various places in the state. It is equally clear, that the slate is the Hudson river slate, and which has been shown in the reports referred to, to be geologically above the Trenton limestone, though here it appears resting against it. We now proceed to speak of the rocks at the fall, and here it is neces- sary to remark, that the strata both above and below will require exami- nation. First, then, above the fall, the rock of the bed of the river is gneiss, and reposing upon the edges of the strata composing the bed of the river is, first, a sandstone, in a horizontal position, loose in texture, large portions of which are stained green by carbonate of copper. It is not over ten feet thick, and is of course unconformable with the gneiss on which it rests. This is the Potsdam sandstone, so largely developed in the northern counties of this state. The next mass, as we ascend in the series, is made up of boulders, some of which are six or eight feet in length; it corresponds to a mass which occurs at Chazy, in Clinton county, and which has been considered as the upper portion of the Potsdam. It is one of the rare instances in which boulders of this size appear as the constituent parts of the regul- arly stratified rocks. Upon these boulders is a compact limestone, with its layers conform- ing to their regular surface on which it-rests. It contains obscure or- ganic remains, principally of encrinites. This mass graduates into a gray crystalline limestone, which is composed mostly of broken encrin- ites; it is about fifteen feet thick. Succeeding to this gray limestone, is the Trenton, a mass very well developed, and abounding in characteristic fossils. It is at least sixty or seventy feet thick, and presents as a whole the characters of this limestone, in as great perfection as at any locality on the Champlain, or in the Mohawk valley. It is worthy of remark here, that this limestone is an excellent!guide in determining the relative position of the lower rocks: it forms an excellent starting point from which to trace the ascending or descending series. It will be seen from the remarks above, particularly by those acquainted with the lower rocks, that two important ones are absent, viz. the Calci- ferous sandrock and the Birdseye. The first is sometimes two hundred feet thick— the latter thirty. This omission is not, however, to be considered as a very remarkable case, though"it must be confessed that the Calciferous is one of the most constant rocks in the Mohawk, and along the Champlain and St. Law- rence valleys. The thinning out and final disappearance of a particular rock is, in fact,_ one of the common changes occurring in the rocky strata. Having briefly enumerated the rocks above the fall, it is time to ex- , Geology of the Monitmorenci— Emmons. 97 amine those below. The first I shall speak of is the one forming the great fall. This is rather a fine grained gneiss, and furnishes from some portions of it, carbonate of copper, which stains the sandstone alread noticed. It rises in a perpendicular ledge, and stretches in an unbroken uniform mass entirely across the gorge. It is a naked wall, two hundred and forty feet high, and serves by its great mass, as seen below, to add to the magnificence of the scene. Against this ridge of gneiss, the black slate of the Hudson river series reposes. Wiewed from above, it appears at the first sight to rest upon the gneiss conformably; but upon a close inspection it will be seen that it is in a nonconformable position; the strata of slate are less inclined than those of the gneiss, and the whole arrangement finally appears to result from a derangement of the masses. But we have in this place several sedimentary rocks of different ages, nearly if not quite in contact, resting upon the primary mass, and it might be quite puzzling to deter- mine which is the oldest,mass, the rocks above the fall or the slate below, as both rest upon the primary unconformably, and only afew years since the slates were placed in the geological systems upon the primary in the precise position which it here occupies. The annexed diagram will serve to explain more clearly the relations of the rocks at the fall. From the facts which have been given, and from an inspection of the diagram, it will probably be conceded that there is at the fall of Mont morenci a fault, or uplift on one side, by which the horizontal masses have been elevated, and a down-heave on the other, by which the slate has been thrown into an inclined position; for an uplift simply would have fractured and elevated the strata, but would have left the slates in their original horizontal position, or perhaps, instead of giving the whole mass an inclined position, would have merely bent their edges. Such a result is not uncommon. An inquiry may be raised at this stage of our examination, if the Black Slate really occupies a position upon and above the Trenton, why is it not to be found still in place? The answer to this question is at hand;, the entire mass of slates, shale and sandstone which constitute the gray- wacke of authors is entirely swept off. The force from beneath which produced this remarkable uplift, shattered and broke the mass of shales, &c , so that they were exposed to the full force and power of floods and currents of water which have swept over the earth at different periods of its history. We are justified also in bringihg to our aid the transporting power of icebergs, agents whose effects and power have been admitted by the most learned and able geologists in Europe and in this country. That this answer or conjecture is more than probable will be shown in the final report of the Second Geological District, the details necessary to establish such a result not being admissible in the present number of this magazine. But to return to the consideration of the fault or uplift which produced the fall of the river at this particular place; we are not to suppose that “98 Geology of the Montmorenci— Emmons. it is a mere local derangement limited to a few rods, but from what is said in the preceding paragraphs it will be seen that there is very little doubt of its extending south along in the direction of the Beauport road and that the places where the Trenton limestone appears or the black slate is found projecting upward in an inclined position, we are on the line of this fault. But this is not all.. We are led to believe, from facts which have been accumulating for several years, that it extends much farther south andis to be found pursuing nearly a north and south course ‘into the state of Vermont, and may be particularly traced on a line con- necting Johnson’s mountain in lower Canada, several points on the Mis- sisque bay adjacent to the provincial line, and also at the remarkable uplift at Snake mountain, in Addison, Vt. A line uniting those points and several others in the same direction, marks the line of a great disturbance which has deranged the lower transition rocks for at least four hundred miles. It may be that this line of derangement is not continuous, and if continuous there are evidently many points}where the force producing it was much greater at some than at others, and which has resulted in the projection of several mountain masses continuous only for a few miles, all of which are on this line, and in this geological formation, and along which we find a remarkable uniformity in the accompanying phenomena. Many of these mountain masses are represented on the est maps of Canada, Vermont and New York, and they may be dis- tinguished from the Green mountains, as they appear merely as outliers in that remarkable range. I do not propose to go into the proof of the whole doctrine which is advanced in this essay, in relation to this extended line of derangement; the space allotted is too limited, and besides the required details are un- suitable to the character of this magazine. There remains one or two importantinquires which may with propriety be placed before the reader before I close, as they are connected with and related to the views which have been expressed in this paper. The first is, may not the great fault which I have supposed to extend through Lower Canada, Vermont and New York, have caused the confusion in the writers on Geology in regard to the lower transition rock, particularly the Hudson river slates and shales? May not the same derangement exist in England and Wales, and have been the cause, at least in part, of their separation from the Silurian system, and of their being considered as one distinct therefrom, and which has been called the Cambrian system ? In this state it seems to be established that we have these rocks (the slates, &c., of Hudson river) in two positions, the horizontal and the in- clined. They occur inthe former position at Pulaski, Lorraine, Rodman, and Pinckney, and they are conformable both in position and fossils to the so-called Silurian sysem. Again they occurin Rensselaer and Wash- ington counties in Vermont, and the entire length of Lower Canada, in an inclined position. Through this great extent of country they are mineralogically the same as the Pulaski and Lorraine shales, and differ from them only in their inclined position. But over this great extent Geology of the Montmorenci— Emmons. 99 they agree with what has been published by English geologists of the Cambrian rocks, leaving of course out of view the lower portions of this system, which are either those of shales in an altered state, or else are the true primary. The suggestion contained in these remarks that the Cambrian rocks are really a portion (but not the lowest portion) of the Silurian, has been a conviction of my own mind for a long time, and I find that others entertain the same views. It is a conviction which has been gaining ground with the progress of discovery, but which has not resulted from any single discovery of itself. But it is proper to notice here one souree of difficulty in regard to the rocks of Hudson river, especially on their eastern border. It is the fact of their overlapping in this direction, the Trenton limestone and the other transition rocks beneath. The consequence has been that, in traveling from east to west, or from Massachusetts and Vermont to New York, we pass directly from the primary mass to the higher members of the transi- tion system, consequently they have placed them upon the primary, and considered them as the lowest of the transition; whereas, there intervenes between these Hudson river slates and primary, the Trenton limestone Birdseye, Calciferous, and Potsdam sandstone, the aggregate thickness of which exceeds a thousand feet. Not one of the lowest members of the transition!system appears in the eastern prolongation between the High- lands of the Hudson and the Highlands north of Quebec, adjacent to the primary, in consequence as has already been said, of the overlapping of those rocks formerly termed graywacke, or now known as the Hudson river series. There are two other difficulties which have served to per- plex and confuse geologists, viz.: the striking mineralogical character of some of the masses of the Hudson river series, to the talcose slates of the primary, and also the great correspondence in kind and amount of their dip. Iam not able for want of space to speak of these difficulties. It is evident, however, that the slates and shales do not conform to the pri- mary, they rather rest against the primary, and though in both the dip is to the east, still the constant dip of the slates is less than in the primary. There is a fact which is worth pursuing and which has some bearing upon this question, that is the slates of the Hudson river and lake Cham- plain are placed between two different mountain systems —the ranges, north of the Mohawk valley, all of which clearly compose one system, and the Green mountains which is another. The force which may have served to produce one or the other of these systems may have caused this remarkable derangement in the slate system, producing at the period’ -of their elevation the derangement called a downheave. The known facts, however, are not sufficient to establish the mode and manner in, which these border rocks as they may be termed, (meaning the slates, and shales), were deranged. They are not of great thickness where they are horizontal, but when inclined, they appear to be immensely thick.. In crossing the formation, for example from east to west, it is apparently 20 or 25 miles thick, for as yet it has been impossible to recognize the 100 Geology as a means of culture—A. Winchell. recurrence of a single stratum in this distance, yet it may be possible hereafter. In whatever manner the force really operated, it seems to_ have produced an effect analogous to that of a plough in turning up successive furrows, leaving them parallel and standing upon their edges. There can be no doubt, however, that in the twenty-three or four miles east of the Hudson, the distance which these rocks extended, there are numerous repetitions of the same layers, for it cannot be supposed for one moment that any of the formations above the primary can be of this enormous thickness, which observation seems to indicate. I must now close my remarks, having extended them farther than was intended when I commenced. I have done this, however, in hopes that some of my observations may induce others to follow out some of the suggestions. Probably there is no field more interesting than the one in which these observations have been made, nor one which isso obscure and which, therefore, will require a multitude of observers before it can possibly receive its full and perfect elucidation. GEOLOGY AS A MEANS OF CULTURE. BY ALEXANDER WINCHELL. ie 3. DIVERSIFIED ASPECTS OF GEOLOGICAL STUDY. Unlike mathematics and many other subjects of study, the science of geology consists of various ranges and kinds of knowl- edge. It is not a mere body of facts of observation, like polit- ical or physical geography in the ordinary acceptation; nor of facts of record, like history in the scholastic sense, It is not merely a field stocked with the products of imagination and_ sentiment, like popular literature. It is not merely a realm of abstract concepts and necessary ideas, like metaphysics. It is not merely a system of deductive processes all firmly bound to- gether and to first principles by necessary laws of thought, like mathematics. It is not merely a department of mental activity where conclusions are balanced on probabilities, and moral cer- titude is the highest satisfaction afforded the aspiration to know, as in many ecclesiastical, political and educational questions. It is allthese, and more than these. Geology as the science of the natural world, embraces all which the natural world contains; Geology as a means of culture—A. Winchell. 101 all with which it is historically and genetically connected, and all the accessories and means whose employment contributes to the attainment of a knowledge of the world in its widest rela- tions. It is the organization of all the sciences in a crusade . for conquest in the realm of the unknown. To illustrate and jus- tify a claim so large, I shall venture to recite in brief the proc- esses by which geology advances from the most familiar facts of observation, step by step through generalizations higher and higher, to the grandest doctrines ever enunciated by science; and thence by a reverse, or deductive process, to the details of events from which actual observation is separated by intervals of space and time to finite powers impassable. The beginning of all this fabric of geological science is what we see by the roadside, in the field, on the mountain slope or the ocean’s strand. In our daily observations are the facts which point the way to the loftiest generalizations of the science. Let me confine the reader’s attention to a group of phenomena lead- ing toward the fundamental doctrine of a cooling globe. About our very doors lie the bowlders whose hard and crystalline char- acter proclaims the agency of intense heat. In the structure of the mountains which we climb, and underneath the lands which we inhabit, are square miles of rock similarly crystalline and vitrified. These are data of observation. They are data of easy and familiar and universal observation. They sustain the inductive conclusion that intense heat has been there. Other observations on ancient lavas—on palisades, dikes and extinct volcanoes, indicate that the heat has been sufficient to fuse the rocks. Has been—but is now no longer. The heat has sub- sided. Thermal springs, geysers, artesian borings, deep mines, vol- canic eruptions supply other observational data from which we induce the doctrine of a heated interior. The earth has cooled, but is still hot within. The earth ts in the midst of a cooling process. This is a most fruitful principle. If the earth is a cooling globe, two inquiries next press upon us. Through what phases of existence has it passed in its remote history; and what vicis- situdes is it destined to undergo in the future continuance of the cooling processes? From what initium did the cooling process 102 Geology as a means of culture —A. Winchell. set forth, and at what finality will it end? No one can fail to understand that these are lofty inquiries; and that any well grounded responses must lift our thoughts into the realm of sublime truth. But the history of the earth’s cooling unrolls a vista through the past eternity. No human intelligence has. been witness of the events. The future career of the cooling globe lies in the folded possibilities of events unreal and stretch- ing into the eternity lying in the opposite direction. But these lofty questions are not unanswerable. The events of terrestrial history succeed according to methods which lie re- vealed. There is no uncertain caprice in their order and rela- tionships. Physical events run in grooves. What we observe discloses a trend which may be followed in either direction. By observation we have learned the laws of cooling, and the ele- mental and climatic changes which depend on changes of tem- perature. Ifthe earth be a cooling globe we may with confidence deduce its conditions and their concomitances in the earlier stages of cooling. Here our reasoning becomes deductive. We proceed from the inductive principle of a cooling globe, and from the primary principles of thermodynamics, and retrace the cooling history. We see in imagination as we recede, a warmer terrestrial surface, a more tropical climate, and, in correlation, more tropical plants and animals. We strengthen and verify the deduction by the inductive data afforded by the successively deeper sheets of ocean sediment. Farther on in the retrospect, the sediments are but beginning to accumulate. The mountains are still in embryo; the ocean is universal. As the scroll of terrestrial history continues to unfold, the ocean itself is noticed at its natal epoch; the clouds are discharging the ocean from their bosom. Here the possibilities of inductive confirmation disappear. Earlier than this no enduring rocky forms had ex- isted. The greater heat had reduced all terrestrial matter to a fluid state, which retained no records. This is the starting point of inductive geology. But this is not the starting point of the process of cooling. With the eye of imagination under the calm guidance of the reasoning powers, we behold in the remoter past, a world of firemist, with the beginning of a central nucleus of molten matter. In the profounder depths of the eternity past, the fire- , Geology as a means of culture—A. Winchell. 103 mist is conceivably in the condition of a gas. In a history of cooling, we have learned of no condition antecedent to this. The gaseous state of matter accompanies the highest tempera- ture known. Do not understand me as enunciating the doctrine that the cooling process must have begun at a temperature at which all terrestrial matter existed as a gas. I mean only, that the process of cooling leads always away from that state as the remotest possibility. Actually, it may have proceeded from a condition thermally subsequent to this. The subsequent ther- mal condition may have been attained from some older state in which the constituents of the world were gathering together, and were yet even at alow temperature. I am not seeking to reason out that condition of the world which was absolutely primordial. I seek only to illustrate how by an inverted de- duction, we may recede toward a state of the world which ante- dates all human observation and even all the rocky records of inductive geology. Now, having found a starting point—having assumed any remote condition as a starting point, we pursue by direct deduc- tion, the course of events which under the laws of matter, must have ensued in the progressive escape of heat from the terres- trial mass. We reason out the attainment, sooner or later, of the firemist condition, the precipitation of a molten rain and the growth of a molten globe, the condensation of aqueous vapor, the enveloping of the earth in a mantle of clouds, the descent of eonic rains, and the gathering of the universal ocean. Many other events collateral with tiese, we logically reason out. By the aid of imagination, the scenes enacted become vivid and real, and our understanding of them improved. Now we see how and when marine precipitation must have begun, how the sub- marine floor by thickening, became melted off by encroachment of heat from below, and how as sedimentary deposits continued, the deep-seated residual heat invaded upward the earlier sea- sediments and transformed them. We see how and when the time arrived for the possible introduction of organic forms, and how they succeeded each other as the rolling xons of cooling wrought the terrestrial surface into changed conditions. Of all these post-crustal events, the crust has retained some records, and the inductive evidences from them check and verify our deductive inferences. 104 Geclogy as a means of culture—A. Winchell. Let us for a moment stand on a higher plane of observation, and rise to a higher generalization. There are other planets within the range of our vision which exist under the same forms and motions and accompaniments as this planet. They are reg- ulated by the same system of laws; they consist of the same matter; they undergo the same visible vicissitudes. Here is a body of data of observation—not indeed, with unaided vision, as when we noted the aspects and conditions of the vitrified and crystalline rocks—but with the aid of the telescope, the spectro- scope, the polariscope and the crucible. From these data we formulate the inference that all the planets revealed through our instruments are bound together in one system, have had a common history and are moving to a common destination. This larger generalization produces in our minds a conscious expansion—a larger apprehension of the scope and unity of the cosmic plan, This higher attainment of thought is attended by a grateful emotion, a spiritual delight; and if we are philosopher enough to contemplate plan as the correlative and expression of mind, we feel here, in the presence of this grand disclosure, a higher certitude of Supreme Mind, and a deeper seated and’ more enduring sentiment of devotion. At the level of this loftier generalization, we conceive the matter and the forms ofall the planets merged in one. Per- haps the common mass is in the state of firemist, and luminous. Perhaps it is a heterogeneous assemblage of mineral particles and masses undergoing condensation, and destined in a later zon, to evolve the heat which will develope luminosity and re- duce portions to a state of firemist. As before, I care not to define precisely the actual state of the matter of the solar system which was primordial. We seek only a rational commence- ment—a condition such as involved all later conditions. There must have been a time—so we reason— when the evolution of heat began to be surpassed by loss of heat. From that epoch cooling and contraction began. Rotation is a primordial, neces- sary condition of all separate masses of cosmic matter. Ina rotating, cooling and contracting spheroid, the changes of form and condition resulting are the subjects of calculation. Even if there be alternative lines of vicissitudes, one of these leads on through processes of annulation and spheration—with possible Geology as a means of culture—A. Winchell. 105 secondary annulation and spheration—on to such an outcome as we see exemplified in the assemblage of planets and satel- lites constituting our solar system. And this earth on which we dwell is a particular outcome of such an evolution —so grand, so vast, so ancient. And all that is now of the earth was involved in those zonic vicissitudes. The bone and flesh and nervous matter of our bodies existed in that primordial fire- mist—in those annulating spheres—in that fervid atmosphere —in those glowing rocks—in those ancient sediments—in the shells of primeval molluscs—in the framework of generations of reptiles—enduring as matter; and our plans of organization give expression to thoughts noless enduring. Such is the unity of the organism of the planetary system, and such the unity of man with the organism of the worlds. In this regressus of thought, we rise to a still higher plane. The sun appears as the residuum of a prolonged process of plan- etation. By the aid of our instruments we learn that the stars are other suns. Imagination kindles and emotion warms at the suggestions of such a fact. The stars then, are so many centres of planetary systems completed. Yes, to the utmost limit of the visible universe, the same modes of world-life prevail as are ex- emplified in our own system—the same as are revealed in con- tinental masses and granite cliffs and ocean sediments on this orb to which we have been assigned as its inhabitants. There must be then, other planets. There must be other inhabitants. If other inhabitants, their intelligence is akin to ours; for other- wise, the universe around them, so interpretable to us, would be uninterpretable to them;and the fitness of things which reigns everywhere within our cognizance, would be turned in- to contradiction of the testimony of the universe. Reason refuses to credit this. Other intelligences there are, to whom the universe has the same meaning as to us; who think as we think; who are already familiar with our ideas, or are ready to receive them and to impart to us their own. Does not the reader find such ranges of thought expansive, ennobling, spiritualizing? Possibly he is saying this is not geol- ogy. No —not in the school-book sense. But geology in the stricter sense leads to the high-swung bridges over which thought passes by an uninterrupted continuity of path into the 106 Geology as a means of culture—A. Winchell. realms of philosophy and theology, whose light tinges the clouds which engirt a primeval world. I suffer myself to follow thought into these remoter realms for the purpose of showing the vastness of the range of geological contemplation, though the ordinary geologist may seldom explore it. Geological facts and doctrines, with which we are all chiefly occupied, lie in a single province of the science. I said that the grooves of passing events run into the distinct future as into the distinct past over which the reader has been transported by a rapid flight. By direct deductive reasoning from the generalized principle of a cooling globe, we are able to depict future vicissitudes with no less certainty than those past. We anticipate a frozen world and a darkened sun. From the generalized doctrine of slow continental degradation we depict beforehand the destructive work of future ages. From the action of the moon on the lagging lunar tide, we are enabled to foresee a lengthened day, and finally synchronistic rotary and orbital movements of the earth, accomplished by a slower action of the sun on the solar tide. Through the operation of a resisting medium—whether ethereal, meteoric or molecular —we look forward to a general gathering of all the dead planets at a common sepulchre. Then by completing the parallelism already delineated in reference to the past, we learn that the unrolled history of this world represents that of all the worlds of our system; and the unrolled history of the system pictures that of the firmament. And now the grand and cul- minating inference of all science looms before our intelligence in majesty awful and inspiring: The history of matter is one in all the bounds of all space and in all the zons of time past and time to come. The vicissitudes of yesterday are a paragraph in the annals of universal matter. In that totality every human life is a constituent part. Man stands in the midst, and casting his mental glances backward and forward, affirms and feels his unity with all. Jax only as an organism. Those glances are not the rays of sun or star—they are the thoughts which imperishable and unchanging mind has written on the forms of star and planet and organism. And thus, out from the forms of matter as they perish and disappear, rises an entity which neither changes nor disappears, nor yet endures as mindless matter— Geology as a means of culture—A. Winchell. 107 but endures in self-consciousness and self activity, and constitut- ing my essential self, unveils to vision another universe where suns neither wax nor wane, and the limitations and infirmities of changeful matter never interrupt or ruffle the gentle current of eternal being. 4. THE INTELLECTUAL POWERS WHICH GEOLOGY CALLS INTO EXERCISE. These thoughts are presented with no intent to expatiate on the themes of science. My purpose is only to indicate the vast- ness of the range of cognitions and contemplations to which the study of geology invites. It begins with simple facts of easy observation. It calls the percipient powers into pleasant exer- cise, In observing separate facts we compare them with each other. By processes of judgment we pronounce tnem identical or similar or diverse. If similar we a@éstract the particular characters in which the similarity consists, and decide whether they are trivial or fundamental. The wide ranges of facts brought under observation are distributed into groups. ames for the facts there must be, and thus arises a technical nomen- ‘clature, which gives us additional exercise in verbal memory. In extending our knowledge of facts beyond the sphere of per- sonal observation, we resort to the records of the observations of others. We are led to the use of foreign languages. We ob- tain the cultural benefits of Ungutstic study. Our various ‘groups of facts lead to various eexeralizations or interpreta- tions. One group points to a former high temperature on the earth, as we have seen. Another convinces us that the lands have been covered by a universal sea, and that the bedded rocks are but its sediments. Another group indicates the magnitude of land erosions in the past, and the complete obliteration of ancient continents. Another group of facts establishes the doc- trine that the earliest animals were invertebrates; and that the oldest vertebrates were marine; and in short, that the order of succession in the advents of animal types was identical with the order of rank—thus contributing one of the principles on which we base that higher generalization which expresses the method of Supreme Mind in all the successions of the natural world. Within each of these broader and more obvious generalizations 108 Geology as a means of culture—A. Winchell. are others of more limited scope. If the first vertebrates were: marine, so the first marine vertebrates were not fishes of typical structure, but of archaic forms now long extinct. If land vege- tation appeared after marine, it was at first only a flowerless. jungle. The great body of geological doctrines consists of in-. ductions like these, founded upon facts of observation. Many, very many of the facts are near and familiar; many are remote and unfamiliar. A large part of the body of geolgical science consists of a record of facts. The generalizations are not, in- deed, postponed till all the facts of the science are catalogued.. We begin to draw our generalizations while yet we must hold. them as merely tentative. Final generalizations may displace them; and even these in some cases, may prove not to be final;, or may prove to be wholly erroneous. By a law of our minds we begin to generalize as soon as two or more cognate facts are brought together; and continually test and revise our gen- eralizations, as long as new facts of the same group prove in- compatible with earlier generalizations. Then we have reached a principle or doctrine. Thus it is a doctrine today that Dino-. saurs did not survive the close of Mesozoic time. But if to- morrow we find the remains of Tertiary Dinosaurs, that gener-- alization must be rectified. Thus in dealing with the great body of geological science,, we keep the observational faculties in training. With this, we exercise the powers of sexse-memory and of language. This. training holds a large place in the exactions of geological study.. So far as trained quickness and exactness of perception consti- tute mental culture, the study of geology is eminently cultural. In dealing with the same great body of the science, we, keep the inductive powers in constant exercise. Their activity, as I have said, is the characteristic activity of modern intelligence, in dis- tinction from medieval and ancient thought. If the training of the mind in those methods of activity which tend to identify it with modern thought, and make it master of the characteristic results of modern thought is a useful training and a desirable training, then the habits of inductive reasoning fostered by ge- ology constitute an eminently valuable form of mental culture. But with these studies come various forms of incidental cul- ture. Many of the facts are recorded in works of travel and de- Geology as a means of culture—A. Winchell. 10g scription written in style of high literary excellence. Allow me to cite Hugh Miller’s “Old Red Sandstone;” Major Powell’s “Exploration of the Colorado River of the West;” Captain Dut- ton’s “High Plateaus of Utah,” and Miss Bird’s “Fire-Foun- tains ;”—or in a different field, the Duke of Argyll’s “Unity of Nature.” If the student is called upon to record his observa- tions, as well he might be, he may acquire a copiousness of dic- tion and a beauty of style not inferior to that promoted by es- says on historical or romantic themes. More indirectly, come the acquisition of languages and the enrichment of the vocabu- lary. With these forms of geological study will be noticed an ac- cessory training of the zmagination. The picturing power is demanded even in bringing into juxtaposition in thought, absent data of observation which have to be compared together. Still more is it demanded in acquiring a vivid comprehension of data presented through descriptions. Especially is this demanded in the study of descriptions of fossil remains unaccompanied by delineations; and not less in the drawing up of such descriptions. I know paleontologists who declare that a mere description of a fossil shell is unintelligible; but, provided the description is good, it would become intelligible with improved picturing power in the imagination. The facts show that in the study of descriptions of fossil remains, and other facts not fully illustrat- ed by drawings, the imagination is kept in constant exercise. The cultural results on this faculty are therefore of great effect- iveness and high value. In an accessory way also, comes discipline in the art of delin- cation. It is impossible for the geological observer to record his observations without the ability to accompany them with drawings. If the student has had no instruction or practice in drawing, he will soon obtain the practice, and then the instruc- tion will be unessential. On almost every excursion, the student or investigator must execute from nature geological sections or geological maps. Not unfrequently, he must delineate some fossil which cannot be removed from the rock, or embody some delineation in a description. I am aware that finished drawings exhaust much time, and are commonly confided to special artists. Still, drawing is one of the demands of geological study and in 110 Geology as a means of culture—A. Winchell. vestigation; and this artistic acquirement is one of the forms of culture for which the science of geology provides. The same demand for pictorial illustration leads the field ge- ologist to subsidize for his ends, the superb picturing power of the photographic camera. Topography, mountain forms, rock- structure, details of stratification, water-falls invite to the appli- cation of the camera while in the field; and the exact delinea- tion of fossil forms is greatly promoted by photography in the laboratory. Thus the geologist is led still further to diversify his accomplishments, and add to the sources of his efficiency as a geologist, and of his enjoyments as a lover of nature. These various forms of mental exercise and discipline are in- cident to the acquisition of the facts and doctrines of geologic ‘science. I have illustrated a higher range of geological truth, and I wish to impress the fact that its acquisition calls into ex- ercise another range of intellectual powers. The faculties of deductive or a priort reasoning come into play in the attempt to proceed from an admitted principle to the particulars which it involves or necessitates as consequences. Geological investi- gation very fregnently takes the deductive form. It does not often proceed from xecessary principles, as in mathematical rea- soning; but generally from a principle or truth established by previous inductive research. When a distinguished American geologist described a large number of three-toed tracks found in the brown sandstones of the Connecticut valley, and ascribed them to extinct species of birds, the elder Agassiz reasoned de- ductively when he declared that they could not be bird-tracks, since birds, according to all inductions, had not begun to exist at so early an age ofthe world. Similarly, the geologist de- clares that coal will never be discovered in the valley of the Hudson river, however black and misleading some of the slates may be; since all productive coal measures have been found to hold a higher stratigraphic position. More marked and pro- longed employment of deductive inference is observed in the treatment of those geological problems which admit of the ap- plication of the methods of mathematical analysis. Some of these problems are as follows: The temperature of the earth’s interior; the thickness of the earth’s crust; the condition of the central matter of the earth; the existence of tidal effects in the Geology as a means of culture—A. Winchell. LIE earth’s general mass; the greatest possible altitude of mountains; the sub-meridional direction of mountain chains; the sufficiency of mountain-wrinkles for the total of mountain folds; the exist-. ence and position of a zone of no stress in the crust of a cooling: planet. Then in that higher range of geological investigation which may be styled comparative geology, or an application of the doctrines of geology to the conditions and histories of other planets, we find many uses for mathematical methods; as in the study of the moon’s atmosphere, and her general physical con- dition; the conditions of Jupiter, and of Saturn and Uranus, and the light they throw on past and future conditions of our own planet. Without the application of mathematical analysis, the general processes of deductive reasoning from the principle of a cooling world, afford, as I have shown, large and valuable exercise for the higher intelligence. It is a regal power by which we ex- plore in thought the distant ages of terrestrial history which elapsed before even the race of man existed, or the ons of cosmic vicissitudes undergone before even the world had ex- istence. It is a regal power by which we may stand here and glance down through the eons of terrestrial changes. yet future. The past has been real, but the future is unen- acted. The intellectual eye, through the telescope of geol-. ogy, pierces through all potentiality. It is prophetic. It en- ables us to live alike in the zons of the past and the zons of the future. It confers on us a limited omnipresence and omni- potence. No enlightened man can possibly deny that such ex-- ercises of mind are lofty, noble, cultural — cultural and improving to an extent scarcely paralleled in the circle of human thought. There are those—among them a few geologists — who affirm that these lofty deductive reasonings are little more than flights of the imagination, and that the results do not belong to the body of recognized science. These men conceive geology as properly restricted to its body of facts and generalizations. It is easy to show that such a dogma is impossible of observance, and is violated daily even by those who acknowledge only. pos- itive geology. But a thoughtful consideration of the mode of evolution of our grand deductive conclusions will show that they are reasoned out, not imagined. The difference between a 112 Geology as a means of culture— A. Winchell. pure romance and a romantic inference is as wide as the begin- ning and conclusion of terrestrial history. It cannot be claimed that the particular denouements which we picture have been or are to be actual events. The pathway of reasoning often bifur- cates, and we may pursue either road to conclusions. There are always concomitances lying alongside, which are the out- comes of causes acting outside of our trains of reasoning. These may determine whether the actual course of events will pursue the right or the left. We know however, that it will pursue one.or the other; or at least some course within the scope of rational anticipation. With all these qualifications and uncer- tainties of actual detail, the sublime fact remains, that our science enables us to mount into the xons past, and plunge into the depths of the eons to come, and get visions, even if dim, of the stupendous events flowing out of the exercise of infinite power and infinite intelligence in the realms of infinite space and infi- nite time. Let me add that if these visions are absolutely unreal, the exercise of the intelligence is still the same. It is an exercise of the loftiest powers of the mind, and if it leaves in our possession no real knowledge, but only culture, it stands on a footing equal with some other studies deliberately pursued simply for their cultural influence and that, even on a lower range of faculties than those employed in the higher inductions and de- -ductions of geological science. It must have occurred to the reader that much yet remains to be said of the cultural influence of the higher reasonings of geology. I allow myself a few words further. Imagination, I said, is not the creator of the histories, past and future, which I have depicted in the vicissitudes of the world; but it is the in- dispensable instrument for securing to the understanding a vivid apprehension of the reality, the nature and meaning. of those vicissitudes. These exercises of the higher reason keep imagi- nation in constant and pleasing activity, and thus train a power which sheds over the logical products of the mind a vivid ra- -diance, and often lights the way for the understanding into the dark regions of the unknown. The loftiness of these themes demands a lofty style. To por- ‘tray them to the common intelligence — always eager to learn Geology as a means of culture —A. Winchell. 113 -of them —demands such imagery and metaphor and lucidity and earnestness as belong to the higher ranges of polite literature. If a good use of language be one of the results of culture, here are examples for imitation, and here are opportunities for scholas- tic exercise. In commencing this discussion, I proposeed to confine my treatment to intellectual culture, but the friends of geology might well charge me with remissness, if I should fail to remind the reader again, of the moral and spiritual improvement which comes from such contemplations as I have pointed out respect- ing the unity of the realm of nature, and the revelation of Supreme Intelligence which we read everywhere in the plans and methods of nature. I could not say more within reasonable limits of space. Enough I hope, has been said to establish the proposition that the study of geology is suited for universal culture. Inits var- ious grades and departments it calls into exercise every power of intelligence, and even comes into moving relations with the ethical susceptibilities. What more is universal culture? What more is symmetrical culture? Who can claim any discipline of intelligence as not reached by the influence of geological learn- ing? I shall not institute comparisons in detail. I leave it to my readers to seek out other lines of study capable of a wider or more profitable culture. Their efforts will but enforce the truth of my conclusion. I am not so unreasonable as to maintain that geology is the only science to be studied; or that other sciences or literatures do not afford particular kinds of culture to a greater extent than geology. I only desire the truth to be discerned and acknowl- edged, and acted upon, that geology is astudy capable of culture more diversified than is found in the pursuit of those studies often prescribed exclusively for their cultural value. I have presented geology simply as a means of culture. I[ hhave not considered it as a means of useful knowledge. An elucidation of the utilitarian side of geologic study would show that in geology we possess the means of uniting general culture with the attainment of useful knowledge. Thus is doubled the claim of geological study upon our regards as educators and promoters of the best civilization. 114 Prof. Amos H. Worthen — Ulrich. These positions being established, it might still remain to ex- amine the relations of geological science to the developing in- telligence of the young. Though this also is a field which cannot now be entered, it would be easy to show that many of the observational data of the science are precisely suited to the stage of intellectual development of young pupils; other data, and the inferential principles of the science, to pupils of pro- gressively maturer years. And finally, it would be easy to il- lustrate practically the observational method of introducing the familiar elements of geology to pupils of tender years, and pro- ceeding by gradual expansion and elevation of the method, to. ranges of geological thought suited to pupils of full maturity. I leave the subject to the reader’s reflections. What I have said is true or untrue, or partly true and partly untrue. If true, educators cannot, as reasonable persons, permit the science of geology to remain under their reproach and neglect as a ma- terialistic science—a “bread and butter science.” They must act; they must acknowledge the truth, and allow geology to come into the enjoyment of its rights in the field of education. If what I have said is untrue, my positions demand an impartial refutation; for a wide and powerful public sentiment is gather- ing at my side. If they are partly true, I shall continue to. maintain that the true is the larger part, until my numerous and powerful literary friends honor my views with the electric light and heat of their destructive criticism. PROF. AMOS H. WORTHEN. BY E. O. ULRICH. Prof. Amos H. Worthen, so long state geologist of Illinois, and curator of the State Museum of Natural History, died of pneumonia on Sunday, May 6th, 1888, at his home in Warsaw, Ilinois. Prof. Worthen was born at Bradford, Vermont, October 31st, 1813, and hence had nearly reached the ripe age of seventy-five years when death overtook him. He was the son of Thomas. Prof. Amos H. Worthen — Ultrih. EDS Worthen, and on his mother’s side, a descendant of the highly esteemed and distinguished Adams family. He was the young- est, save one, of thirteen children, and received his education in the common schools of his native town and at Bradford’s then famous academy. On January 14th, 1834, nearly a year before attaining his majority, he married Miss Sarah Kimball, of Warren, N. H., who proved his faithful and life-long companion, her death having preceded his only a little more than a twelve- month. In August, 1834, he emigrated to Kentucky, but before the close of the year he began teaching school at Cum- minsville, now a suburb of Cincinnati, Ohio.' Here he re- mained for two winters when, in June, 1836, he removed to Warsaw, Ill., which became his permanent home. With his brothers-in-law, the Kimball boys, he became first a forwarding and commission merchant and later dealt in dry goods at War- saw. In 1842, influenced by the depression in business, caused by the Mormon difficulties in Hancock county, he removed with his family to Boston, Mass., returning, however, in July, 1844, to Warsaw. Before going to Boston his attention had been strongly attracted to the geological features of his new home and the fossils preserved in the sedimentary rocks of that region. The geode beds in particular had commanded his ad- miration and close investigation. Even at that early period he felt within him the stirring of that spirit of investigation and love for natural science that later caused him, first to neglect, then to abandon entirely all business less suited to his tastes, and to devote himself to science witha singleness of purpose and a devotion as rare as it is honorable and profitable to the individ- ual and to mankind. Armed with basket and hammer, all his spare moments at that time were spent in rambling over the bluffs and among the ravines, so that soon his collection con- tained many beautiful and interesting geological specimens. When he went to Boston he took with him sevaral barrels of fine geodes then so abundant at Warsaw. These with a nat- uralist’s true love for his (to be) calling, he exchanged, instead of selling them, for a cabinet of sea-shells. Similar forms to 1In 1886 the writer had the pleasure of escorting the old gentleman about Cumminsville, which he had not seen for fifty years, and he (Prof. W.) was more than gratified to find his old landlord still alive and hearty. 116 Prof. Amos H. Worthen— Ulrich. these shells were preserved in the limestones and shales of his locality, and he worked diligently to learn something of their history and of the specific characters of the animals to which they once belonged. This task was one of great difficulty since the only works he had been able to obtain that contained any account of fossils were Dr. Mantell’s “Medals of Creation” and “ Wonders of Geology,” both published in England. These threw but little light upon the specimens he had gathered, but they gave him an insight into the manner in which the rocks had been formed and how the remains of living forms came to be preserved in them. His collection grew apace and soon began that extensive sys- tem of exchanges with other scientists that gradually not only furnished him with the information so much desired, but also made both his cabinet and knowledge valuable enough to com- mand the attention of leading eastern geologists. Many of his fossils were loaned by Prof. James Hall and illustrated in the report on the paleontology of Iowa. Prior to this time (it was in February, 1851) a law had been passed authorizing a geolog- ical survey of Illinois, and two years later an appropriation was made to carry it out, and Prof. Norwood appointed state geologist. Prof. Worthen did some work under him but soon (in 1855) engaged in more active work in Lowa under Prof. Hall. {In the meantime the work in [Illinois languished; although five years passed, no report was made and when on March 22nd, 1858, Gov. Wm. H. Bissell placed in the hands of Prof. Wor- then his commission as state geologist, nothing of prior work came to his hands save a report by Prof. Norwood on the lead mines of Harden county and the field notes of his assistants. On taking charge of the survey Prof. Worthen at once began earnest and active field work, in prosecuting which he has proba- bly carried a greater bulk and weight of geological specimens than any other geologist of his day. He also secured for the work the assistance of some of the ablest specialists —notably Prof. Leo. Lesquereux in paleobotany and Carboniferous strati- graphy, Dr. J. S. Newberry and Prof. Orestes St. John in vertebrate paleontology, Prof. F. B. Meek and Mr. E. O. Ulrich in invertebrate palzontology, Prof. J. D. Whitney in mineral- Prof. Amos H. Worthen— Ulrich. 117 ogy, Dr. J. V. Z. Blaney in analysis, and Mr. Henry Engleman in chemistry. Healso had the countenance, support and friendly aid of numerous lovers of science in all parts of the state, and though hindered and harassed by unscrupulous and ignorant Opposition to the survey, as so plainly stated in the preface of the first volume of his reports (published in 1866) was enabled to issue a series of seven volumes which are of great scientific value and a credit and honor to the state, while they are to him a monument of industry and ability. He had also the plates and manuscript of an eighth volume complete, but its publica- tion was delayed by the trouble about the state printing during the last session of the General Assembly. This volume was considered by him as the final one of the series, and, believing his mission to be accomplished, he intended to resign his position at Springfield as soon as it had passed through the printer’s hands. Prof. Worthen’s labors related principally to the Carbonifer- ous series. To him belongs the credit of being the first to work out the true relations of the principal divisions of the Lower Carboniferous system, though the inflexible rules of priority may demand that the names proposcd by other laborers in this field should stand for them. The value of his work was recog- nized by his election as honorary member of several European scientific societies. He was also a member of the National Academy of Sciences of this country. Regarding his character the more salient features were: great love for scientific truth and justice, simplicity, unbounded affa- bility and unswerving integrity, coupled with an unpretentious yet strong desire to accomplish a useful career. His generosity and charity scarce knew bounds, while, in his public and private life, his frank and sympathetic nature and unassuming, yet dig- nified demeanor won the esteem of all with whom he came in contact. 118 Editorial Comment. EDITORIAL COMMENT. THE RARLIAMENT OF SCIENCE IN THE UNITED STATES. It is the task of the historian and sociologist to determine how far the example set by the fathers of our republic in reverting to the old and eminently just idea of representative and popular government, influenced the action of all guilds, professions and. classes of society in making concert of action in order to secure greater power, broader views, and more systematic progress 3. but it is certain that the idea of combination has been growing steadily during the past century until scarcely a case where it will apply is untried. Corporation, corner, and trust on the side of capital are met by organization, boycott, and strike on the part of labor; and from the editorial staff composed of the ambitious pupils of the boy’s schools to the eastern alliance of undertakers, every temporary association of human beings either through personal propinquity or a community of business interest is made to produce that strange thing, abstract in reality, yet so much wiser, stronger and more formidable than any one or two of the component parts of which it is formed, called a society. Of course this tendency has extended itself to science which is of the classes which can derive the greatest benefit from such community of work and unity of purpose, because creative + science or original research, in penetrating beyond the domains of the known, needs every help which the most varied ex- perience and the soundest induction can give it, and these are derived not from a few but from many minds. It is true that here is a class of soi-disant geniuses which keeps itself from being entirely forgotten by denying the utility of all those pos- tulates which centuries of experience have produced, who suc- ceed in imitating real genius only in the degree and not in the kind of its eccentricities, and in nothing else. This class is de- lighted in making the plodders stare at its sweeping denials of all the fundamental principles to which the investigation of truth for its own sake has led, and substitutes for them a smart Editorial Comment. 119 sounding paradox which too often is to sciolists what the sepia is to the cuttle-fish; but the large majority of those who do the scientific work of the world are neither deceived nor diverted by this charlatanism, and prefer to seek strength in numbers and a near approach to accuracy in averages. Gradually the idea grew, probably insensibly to its promoters, until from a mere chance gathering of a few scientific men in- terestéd in geology, a confederation of scientific workers arose which includes within itself every domain of human thought applied to the discovery or evolution of new truths. This con- federation is called the American Association for the Advance- ment of Science, and it is the Home of Representatives of American science.' Of course the Senate of science in the United States must be 1Note. The first session of the society which organized as the “As- sociation of American Geologists” was held in the rooms of the Franklin Institute of Philadelphia on April 2. 1840 or a little more than 48 years ago. There were present Edward Hitchcock, Amherst, Mass., Lewis C. Beck, New Brunswick, N.J., Henry D. Rogers, Phila., Lardner Van- uxem, Bristol, Pa., Wm. W. Mather, Brooklyn Ct., Walter R. Johnson and Timothy Conrad, Philadelphia; Ebenezer Emmons and James Hall, Albany, N. Y., Chas..B. Trego, James C. Booth, M. H. Boyé, R. E. Rogers, and Alexander McKinley, Philadelphia; C. B. Hayden, Smith- field Va., Richard C. Taylor, Philadelphia, Douglass Houghton and Bela Hubbard, Detroit Mich. Prof. Hitchcock was appointed chairman and Prof. Beck secretary. The second annual meeting was held in the Academy of Natural Sciences of Philadelphia. Prof. Silliman took the chair. The third session was held in Boston. Dr. Morton the chairman being absent Prof. Locke was called to the chair. Lyell was present at this meeting and “offered some observations on the distribution of boulders aud furrows in the rocks, citing the results of many observations in Europe. A constitution and by-laws were adopted and a list of 77 gentlemen “who had been present at the meeting or had presented communications to the Association” was added to the printed proceedings of the three meetings. The Association adjourned to meet in Albany on the fourth Wednesday in April, 1843. These notes are followed by 462 pages of transactions and 22 well executed plates. [See Reports rst, 2nd, and 3rd., meetings, Am. Ass. Geol., and Nat., Boston; Gould, Kendall, and Lincoln, 1843. fie Boston meeting of this body (which had become the Association of American Geologists and Naturalists”) held in 1847, it was agreed to resolve itself into the American Association for the Advancement of Science. It met for the first time in its new form in the Academy of Nat. Science in Phila., on the third Wednesday (20th, day) of September 1848. Prof. Wm. B. Rogers, the last president of the former organization introduced Wm, C. Redfield Esq. the first president of the new one. See vol. 1, of the Proceedings A.A. A. S. Phila.; Jno. C. Clark, 60 Dock St.) 120 Editorial Comment. assumed to be the National Academy of Science, both on ac- count of its limited membership and the exclusive manner in which additions to its members are made. A few words will be devoted presently to a consideration of how well these two bodies carry out their mission. The objects of the popular body of American scientists are said to be’ “by periodical and migratory meetings to promote intercourse between those who are cultivating science in differ- ent parts of the United States; to give a thorough and more general impulse, and a more systematic direction to scientific research in our country; and to procure for the labors of scien- tific men increased facilities and a wider usefulness.” The first part of these objects sufficiently explains why the meetings of the Association are not exclusively given up to scientific discussion. One important function of these meetings is to enable men of the same or cognate branches of science to meet, compare notes, make each other’s acquaintance and secure those numberless and nameless advantages which only personal intercourse can secure. For this reason as much time as can be spared from the sessions of the Sections is well employed in social reunions which are not of a character to interfere with the talking either of “shop” or of commonplace between contemporary workers in science. These recesses are well employed in doing this, and probably bear as much fruit in the end as the more technical discussions of papers, which latter are necessarily much restricted owing to their large number and the short time which is available to hear them. But too much time ought not to be devoted to these recesses under the guise of receptions, garden parties, excursions, &c., &c., because every meeting of a large number of persons from widely separated districts offers an opportunity for the system- atized exchange of ideas (as in the discussion of papers in Sec- tions and the like) which it costs a great deal of money and exceptionally favorable circumstances to bring about. There is one respect in which the leaders of our scientific Congress are derelict, véz.: in allowing the desire to excel previous feasts to 1 See first paragraph of “ Objects and rules of the Association,” vol. i. EOC A. WAZANT Sia Editorial Comment. i2t inspire the ambition of the citizens of the place where the Asso- ciation meets to outdo all records of hospitality, and by this to encroach upon the precious time which might be devoted to mutual efforts to get nearer to our goal. Another fault is in filling the five days of the meeting too full. It is marvelous that the local committees will never grasp the fact that the visiting members of the Association ever want to be let alone—to be free to do whatever they please, or to rest from the whirl of kaleidoscopic changes and deeds with which it is a local committee’s pleasure to surround its helpless victims. Take an instance haphazard from the little document called the “ Programme A. A. A. S.,” omitting names of persons and places.) o) First day.— Morning. Meeting of Standing Committee at 9 A.M. Or- ganization of Association meeting in general session atio A.M. Meeting called toorder. Invocation by Resignation of chair to the pres- ident elect. Welcome on behalf of local Committee by Reply by the president elect. Announcements by general secretary. An- nouncements by permanent secretary. Announcements by local secre- tary. Morning sessions to begin at 10 and close at 12:30. Afternoon session to begin at 2 and ccloseat(?), * * * Adjournment of gen- eral session and organization of the Sections in their respective halls. Each section is to elect one fellow to the standing committee; three fel- lows who with the vice-president and secretary shall form the sectional committee; one member or fellow tothe nominating committee; three members or fellows to act with the vice president and secretary of the Section to recommend to the nominating committee a vice-president and secretary for the next meeting. Secretaries of Sections report the or- ganization to the general secretary. Secretaries of Sections report pro- gram of their respective section for the next day.— Afternoon addresses of the vice-presidents in their respective halls. Avening: Address of retiring president in general session. (First day pretty well filled.) Second day.— Morning: Meeting of Sections in their halls, 10 to 12:30 and 2 to 6.—Evening: General reception to members and their families. Third day.— Morning: Meeting of Sections at 10 to 12:30, and after- noon 2to 4. Evening: Reception. Fourth day: Excursions all day. Fifth day: Meetings of Sections, 10 to 12:30. Afternoon.— Meetings of Sections, 2 to 6. Excursions during the same afternoon. Lvening.— Two receptions. Same evening lecture and collation. Sixth day Mornug. General session. Election of officers for next meeting and decision of place of meeting. Meeting of Sections till 12:3o. Afternoon.— 2 o’clock meeting and final adjournment of Sections, ven- ing.— General session. Concluding exercises and adjournment. 122 Editorial Comment. Summing all this six days work up it amounts to this: The first day is consumed in organizing and listening to addresses; the sixth day is consumed in electing officers and winding up the affairs of the meeting. Of the remaining four days one is entirely given up to excursions; another is half given up to the same purpose. Or in other words thirteen hours are given to organizing and disorganizing; sixteen hours to excursions dur- ing the day, and (at a most liberal estimate) fifteen hours and a half are devoted to the business which has ostensibly called this crowd of people together from distant parts of this and sometimes of other continents. That is to say, counting as the average one day and a half, which it has taken them to reach the place of meeting, and the same time to get home, there have been spent out of 216 hours in all 151% hours in the discussion of subjects of science. Taking the Buffalo meeting of 1886 as a sample of the num- ber of papers which are disposed of at an ordinary meeting at the present time, it will be found that excluding the addresses of the vice-presidents, there were papers read as follows: Read. Read by title. Section A. (Mathematics and AStronomy)..............cccceeeeeeeees val cet dl Bj (EELYSICS) cabs ce a iakeccvaceecses ob) noecoanccetete cones ner decsane beac 19 8 COE NGS, ee ( CHEMISULY) Paauasten cet ccoeccleuonteaecetcccevapectsceatices ecase-os — 380 ESD). MeChanicals science) se se. sceucecotpesccnetces \ecccesne-acetese 13 6 [Gr Hy (Geology, andi GeGeraphiys)i.cc.cecescesscteestats Croix. The St. Croix beds (so-called western Potsdam) of the Mississippi valley. The Georgia group. Taconic. The Taconic black slate and granular quartz. Paradoxides beds of Braintree, Mass., and St. John’s Acadian, Group of New Brunswick. " | 5 oS = — n 7) mH iS — 3 — S a ) om i) T 3) _ S S) o ss r perhaps gulf of) Warren—a name given to the sheet of water covering the basin of all the great lakes. A succession of beaches of this lake has been par- tially worked out in Canada, Michigan, Ohio, Pennsylvania and New York, covering many hundreds—almost thousands—of miles. Every- where the differential uplift hasincreased from almost zero about the west- ern end of the Erie basin to three, five, and, in the higher beaches, to from five to nine feet per mile. With the successive elevations of the land this lake becomes dismembered, as described in the succeeding pa- pers—and the present lakes had their birth. The idea that these beaches in Ohio and Michigan were held in by glacial dams to the northward is disproven by the occurrence of open water and beaches to the north, which belong to the same series, and by the fact that outlets existed where placid dams are required. (4.) With the continental rise described in the last paper—owing to the land rising more rapidly to the northeast—lake Warren became dis- membered, an | Huron, Michigan and Superior formed one lake; the Erie basin really was lifted out of the bed of lake Warren and became drained, and Ontario remained a lake at a lower level. The outlet of the upper lake was south-east of Georgian bay by way of the Trent valley into lake Ontario at about sixty miles west of the present outlet of this lake. The waters of this upper lake were 26 feet deep over this outlet into the Trent valley, and long continued to flow through a channel from one to 348 Review of Recent Geological Literature. two miles wide. It has cut across adrift ridge to adepth of 500 feet, as the whole area has been rising. With the continued continental uplift to the north-east (which has raised the old beach at the outlet about 800 feet above the present surface of lake Huron) the waters were backed south- ward and overflowed intothe Michigan basin and into the Erie, thus making the Erie outlet of the upper lakes to be of recent date. This is proven by the fact that the Georgian beach which marked the old surface plane of the upper great lake descends to the present water level at the southern end of lake Huron, and is beneath the surface of the water upon its south-western side as the uplift, which has been measured, was to the north-east. (5.) The Erie basin is very shallow,and upon the dismemberment of lake Warren, was drained by the newly constructed Niagara river, (except per- haps a small lakelet south-east of Long point, Subsequently, the North- eastward warping (very much less in quantity than farther northward at the Trent outlet) eventually lifted up the rocky outlet and formed Erie into alake in recent times, thus making Erie the youngest of all the lakes. The beaches about Cleveland are not those of separated lake Erie, but those of the older and original lake Warren. “Les dislocations de Vecorce terrestre.” By MM. pe MArGERIE & HEM. In this work the authors have given an exhaustive monograph on the various kinds of displacements occurring in the crust of the earth, their appearance and their effects. Beginning witha simple fault in hori- zontal strata, they discuss the different kinds of faults and their results on thestrata, horizontal or inclined,in which they occur. ate cio sielsi als (a(e @ (els) a)\= « e)e-0)001 4 A PERIRICN SALON ere seaicters chasis 6 alefeia risrsiet sie sieie\s)eln s/s ols s/elsieisie/s.alelse\8is 11 PE MEMIMNOUS SALES, «cies x:c,Ge'ccc s apveiclel ss cleae on ejel's se ete pwaieieis 1 10. Impure limestone..........,.6. cece cece cece ee cee Bee agen aanO 6 9. Impure shaly coal.............5 2 cece eee sere et cece ens cens 1 2 8. Light colored clay shales............----.eeee seen eee eeee 8 eMMSUEDITIUMOUSISIVALOS 21 ro. 61c,cisyelni's)ersie etaslo: oy e).2s hele sole! eieisley is / £ hight oie Un ateaet tasjoia esate ators 5.56 Ke & length of spinous process*....... .. 2.75 as Gs “s i TAD e cats gare einiie Sean eblale 3.94 4 e* ry horizon. diam. of rib at neck (about) .. 1.00 x ss uf vertical ‘“ “ diapophysis at articulation with rib ........... .. 2.07 Ke i ee horizontal diameter of diapophysis at articulation with rib......... .. 1.75 Length of one of the swimming-paddles, partially restored and including femur (? humerus), about................. 4 5.50 Breadth of same across base of intermedium................ .. 8.20 o. s “ tenth phalanx from tip of third digit. .. 3.13 Length of femur (? humerus), about.............ccceceecees 1 7.00 Greater and lesser diameters of shaft of a femur (? humerus) 3.50 at point where latter is most nearly cylindrical, respectively .. Ee ea Thickness of femur (? humerus) at distal extremity.......... .. 2.63 Breadth of same at distal extremity..............0ccccceeee «- 9.50 5.27 Greater and lesser diameters of head of same, respectively... .. and 4,52 Pareumrerence Of HECK Of (SAME)... o.oo oo cole coe es cheeses 1 1.75 temestiemeth Of tibia (Pradius). 6). 6c... ese cee acces ae 3.44 “ PRU OL BAUROMEIS Neale enlace wa tlc vsttrcne bs sais gtwlel toe 4.63 5 MoramirisOk tiie) CY AD) isla’ c, devas dicts av ole: slaye ee aisidie las 2.30 ES PIPOAMITGO LE, BANNG)./2) < Siclaia lalate bial v ojevs es,0armce'c Gretovai eis a 'eap-er hed 3.00 A fuller paper on this peat with illustrations, will appear in the Bulletin of the Washburn College Laboratory of Natural History, Topeka, Kansas. KEOKUK GROUP AT CRAWFORDSVILLE, INDIANA. By CuHas. 8. BEACHLER. The rocks of the Keokuk group, consisting of soft sand- stones, limestones and clay shales, occupy the entire central area of Montgomery county, Indiana, extending ina broad belt from north to south across it. They are everywhere, except along the streams and hillsides, hidden and covered with glacial deposits from one to one hundred and fifty feet in depth. In drilling for natural gas the drill penetrated two hundred and eighty feet of shales and limestones of -this formation before reaching the shales of the Devonian. The following section was observed at the crinoid beds: 408 Keokuk Group at Crawfordsville, Ind.— Beachler. Feet. Sandstone; containing; fossilss'2)ci 2c iere pic lalesere edie erase teats, Um Riviere 50 Blieishtale,crinOid’ beds. \ <\..6\e'e ys eidis'e dav ele BIG Y ails wasp cle einie lee ae ee 5 Teimestome jencrimal Ne50i saves ichevese: opesereleyatel aye eiaiiateiapecete inte Asletete leis arelener sae eats 2 Blue shale; containing foseils'... oi. <../5:. aie a'e nies wicks! «a seleus + abl eyale Celene 25 62 The Keokuk series is wholly of marine origin, this being de- termined by the remains of plants and animals, the plants be- ing fucoids and the animals being corals, crinoids and marine shells. The overlying arenaceous rockin places, marks dis- tinctly the wave action of the sea. In the argillaceous and calcareous rock the lamination is regular and generally thin, the intervals of quiet being marked by the massive beds. The horizontal position of the strata was assumed in obedi- ence to the law of gravity; and after elevation parallel with the Cincinnati anticlinal, the variation was slight, dipping toward the west. The ‘‘geode bed” which forms the upper series of the group in Iowa and western Illinois, is wanting at this locality; the fifty feet of regular bedded calcareous rock exposed at Keo- kuk, Iowa and Nauvoo, [Illinois is represented at this locality by fifty feet of arenaceous and argillaceous rocks; the lowest series of the group, consisting of cherty limestone and forming the transition beds between the Keokuk and Burlington groups is also wanting at this locality. It will be seen from the above facts that the Keokuk lime- stone on the west border of the central coal field, becomes arenaceous on the east. The Keokuk group, like all of the Sub-carboniferous forma- tions, thins out and disappears east of this locality. The characteristic fossils of this formation are the