OE 923 .K56 Knowlton, Prank Hall The Jurassic flora of Cape Lisburne, Alaska DEPARTMENT oK THE INTERIOR UNITED STATES GEOLOGICAL SURVEY GEORGE OTIS s;.MITH. Director Professionai. Paper 8.5— D THE JURASSIC FLORA OF CAPE LISBURNE ALASKA BY F. H. KNOWLTON Published .litiiiiary '-iS, 1!H4 PART D OF PROFESSIONAL PAPER 85, "CONTRIBUTIONS TO GENERAL GEOLOGY 1913" WASHINGTON GOVERNMENT PRINTING OFFICE lit 14 3 \^B^ CONTENTS. Page. Introduction 39 Tlie ( onviii formation 39 Plant collccl ions 40 Age of the plant-bearing beds 41 Distribution of Jiirassic floras 43 Geograpliie range 43 Means of dispersiil 45 Avenues of dispers;il 45 Probable climatic conditions 46 The flora 46 ILLUSTRATIONS. rage. PilAtes V VIII. JuTaaidc ikfra of Cape Lisburne, Alaska 57-64 II THE JURASSIC FLORA OF (WPE LISBURNE, ALASKA. Bv F. IL Knowlton. INTRODUCTION. A })eculiar and iibsorbiiig interest attaches to the study of the fossil floras of the arctic regions, for they indicate climatic conditions very unlike those now existing m those regions. In place of the present snow and ice and the scant, almost perpetually frozen soil which sup- ports but a handful of depauperate plants, the conditions from at least late Paleozoic to middle Cenozoic time made an abundant and luxuriant vegetation possible, at least during certam periods. ^Vlthough these lands are now so mhospitable, and hence but rarely visited, an astonishiiig amount of information concernmg their fossil floras has been accumulated, and to this kiiowledge Alaska has contributed its full quota, though doubtless much more will ultunately be lvno^\^l. The recent i)ublication of a report by Prof. A. C. Seward on the Jurassic plants of Amur- land, long kno\vn from the historic researches of Oswald Heer, has called to mind the existence of a considerable collection of similar plants from the vicinity of Cape I^isburne, Alaska, that has been m my possession for a number of years. As it is now possible, with Seward's paper in hand, to recognize still further the strildng resemblances between the Jurassic floras of Alaska and Siberia, it seems an opportune time to present the results of this recent study. A prelimmarj' examination of this material was made, and certain tentative identifications were adopted in a short report for the use of the geologists who collected it, but this is the first time it has been aderiuatelj^ described and figured. The material considered in this paper was collected in 1904 by Arthur J. Collier, of the United States Geological Survey, while engaged in a study of the geology and coal resources of the Cape Lisburne region.' The coal dejiosits are extensive and are the only mineral re- sources of the region kiiowm to be of commercial importance. Collier describes the locality as follows: Cape Lisburne is the bold headlaiul which marks the northwestern extremity of a land mass projecting into the Arctic Ocean from the western coast of Alaska between latitudes 68° and 69°. It lies 160 miles north of the Arctic Circle, about 300 miles directly north of Nome, and is the only point in Alaska north of Bering Strait where hills above 1,000 feet in height approach the sea. So far as known, the rocks of the Cape Lisburne region are all sedimentary. The age represented, with the approximate thickness of each, is given by Collier as follows: Devonian ( ?), 2,00n+ feet; Lower Carboniferous [Mississippian], 4,500+ feet: I^pjier Jurassic, 15,000+ feet; Lower CretaceousXO) 10,000+ feet; Pleistocene. 50 feet. THE C ORWIN FORMATION. The Jurassic section to whicli tlic name Corwiii fonnatiou lias been given is described by Collier^ as follows: The older of the Mesozoic formations, which takes its name from Corwiii Bluff and tlie coal mines there located, is best exposed on the coa.st at a point 26 miles cast of Cape I.isljurne and thence extends norlheastward (« Cap(^ Beau- fort, a di.itance of 40 mile.s. which i.s the limit of this investigation. It is known to occur again near Wainwright lidet ' U. S. Gcol. Survey Bull. 278, pp. 1-54, Pis. I-IX, 1906. ' Op. cit., p. 27. 39 40 COXTIUBUTIOXS TO CEXEKAL GEOLOGY, 1913. KM) miloslieyond (^apo Beaufort, ami iIkto is .some iciisoii lor tlie holicf that it is i-oiiliniious to tliat point. Tlicsoiitliprn l>()iiiialniata Heer. Chondrites (iliciformis n. sp. Lesquereux concluded th.nt the age of the l)eds w;is probably Neocomian. In 1800 II. D. Dumars made a .small collection of jilants from the Corwin coal mine, wliicli came ultimately to the United States National Museum. This collection, together with ail <>f the Woolfe material, was elaliorated by W. M. Fontaine for Lester F. Ward's nionograiih "Status of the Me.sozoic floras of the United States." ^ Fontaine revised and changeil many ' Zoology of Captain Beccliey's voyage, Geology, p. 173, London, 1839. « r. S. Nat. Mils. I'roo., vol. 10, p. 36, 1887; vol. 11, pp. 31-.3.'i, 1S.S8. ' V. 8. Oeol. Survey Mon. JS, pp. 153-175, I'Is. XXXIX-XLV, 1905. THE JUEASSIC FLOKA OF CAPE LISBUKNE, ALASKA. 41 of Lesquereux's determiurttious and as a final result of his studies gave the following list of species: Chondrites filiciformis Lesq. Diiksonia saporlana Heer. Onychiopsis psilotoides (Stokes and Webb) Ward. Cladoplilebis vacrensis Ward. Cladophleliis alata Font. Cladophlebis luittoni (Dunk.) Font. Podozamites distantinervis Font. Podozamites grandifolius? Font. Baiera gracilis (Bean) Bunb. Ginkgodium? alaskense Font. Ginkgo digitata (Brongn.) Heer. Ginkgo huttoni (Sternb.) Heer. Ginkgo liuttoni magnifolia Font. Nageiopsis longifolia Font. Fontaine discussed this flora at some length, his final conclusion beoig stated as foUows: "The age of the formation yieklmg the Alaskan fossils, as indicated by them, is not older than the Lower Oolite and not younger than the Lowei' Cretaceous but is probably between them.'" On the basis of this statement Ward called the Cape Lisburne plants "Jurasso-Cretaceous." In the prelunmary study of Collier's material I took occasion to go over some of the identi- fications made by Fontauie and felt obliged to dissent from several of them. For example, the specimen which Fontaine determined as Podozamites distantinerv-is P^ont., a well-knowni Potomac species. I called P. lanceolatus latifolius, a Jurassic form. It appeared that Fontame's great familiarity with the Potomac flora ha Am. Jour. Sri., 4th ser., vol. 30, p. 50, 1910. 2 U. S. Oeol. Purvey Hull. 2TS, p. 29, 190t!. 42 CONTRIBUTIONS TO GENERAL GEOLOGY, 1913. a small later collection, was studied by Fontaine, who was somewhat in doubt as to whether it was Jurassic or lowest Cretaceous, the final compromise being to call the beds Jurasso- Cretaceous. I have long regarded the material as of Jurassic age, and the critical study of the ColUer collection a])poars to have proved this assignment beyond reasonable question. Of the 17 species from the Cape l.,isburne region noted in the jjresent pajjer, the folio whig also occur in Amurland, eastern Siberia: Coniopteris iurejensis, C. hymenopJiyUoides, Podo- zamitfs 1/incfolatvs, P. I. ricJiwalcIi. Phaiiicopsis spcciosa, P. angnstifoUa, Giril-ffo cligitaia, and Pityophyllum nordenskioldi. These Amurland beds were regarded by Ileer as belonging to that portion of the Middle Jurassic (Brown Jura) kno^\^l as the Bathonian, and so far as kno^^Ti to me, this assignment has not been disj^utod. Seward in his late ])aper says: '"The flora as a whole agrees closely with richer collections from ^fiddle Jurassic strata." In 1S76 Heer ' described a large number of Jurassic plants from the Government of Irkutsk, eastern Siberia, and in 1911 Seward and Thomas - reported on a small collection from the JJalagansk district, in the same province. After making allowance for the changes in nomenclature there appear to be in these Irkutsk collections the follo^ving species in common with those from Cape I.,i.-;burne: Coniopteris hurrjensisf, Ginl-go digitata, Phcenicopsis speciosa, P. (ingiisti/olia, Podozamitcs lanceolaius, P. I. cichwaldi, and Klatides curi'ij'olia. A large collection of plants, in the main very well preserved, from beds regarded as of Bathonian or lowest Callovian age, near Kamcnka, district of Izium, Government ol Khar- kow, was described by Thomas'' in 1911. The following species from Cape Lisburne are represented hi this flora: Coniopteris hymenophylloides, Chdophleiis Tiuttoni, Ginkgo digitata, Klatides curriJoJia, Otozaniites glganteus, and Podozandits laneeoJatus. A small collection embracing 14 species from the western border of Mongolia, in Cliinese Dzungaria, was described by Seward'' in 1911. The Mesozoic strata of this region, accordmg to Obrutschew, who collected the plants, reach the enormous estimated thickness of 3,500 meters, thus a])])roaching the thickness recorded by Collier for the Cape Jjisburne region. The following species are common to the two localities: Coniopteris hymenophylloides, Ginkgo digi- tata, Plumicopsis angvsllfoUa, and Podozamitfs lanceolaius. On the basis of the jilants the beds are correlated by Seward with the Middle Jurassic rocks of England and other parts of the world. Seward calls attrition to the "remarkable resemblance between Rha-tic and Jurassic floras as regards general facies," and adds: '"It appears to be certain that some types persisted from the Rha^tic ])eriod to the middle or even to the latest stage of the .Jurassic era." This resemblance will 1)0 alluded to later. Seward '' has dcscribcHl a small flora from Caucasia and Turkestan, from beds of Middle Jurassic age or older, which includes the following species found also at Cape I^isburne: Coniop- teris hymenophylloides, Podozamites hnceolatus, Ginkgo digitata, ami Phanicopsis angustifolia. In 1S76 Heer" described over 30 species of plants from the vicinity of Cape Boheman, Spitzbergen. The beds in which they were found were regarded by Heer as belonging to the Brown Jura (Bathonian), and Nathorst,' who revised the flora in 1X07, then conlirmed tliis position, but later' he |)rocured evidence which induced him to regard the age as near or above the Oxfordian that is, in the U])per or White Jura. Tiie species from Cape Boheman represented in the rocks of (^ape Lisburne are Podozamites lanceolaius, P. I. eichwaldi, Ginkgo digitata, PJianicopsis angustifolia, and Pityophtjlhiiu nordenskioldi. In the ])aper last cited Nathorst also enumerates anew the Upper Jurassic plants from Advent Bay, Spitzbergen, Fitldenia nordenskioldi and Klatides curcifolia Itcing in common with Cape Lisburne. The flora of Franz Josef Land, regarded by Nathorst as younger than ' Ilcer, Oswald, Floni fo.'tsilis aroticn, vol. 4, pt. 2, pp. 28-S<(, 1876. • Com. gik)l. Mi'm., new sor.. pt. 73, 1811. > Idem, pt. 71, 1011. « Idem, pt. 75, 1911. ' ' Idem, pt. :)S, 1907. • llccr, Oswald, Flora fassIUs arctica, vol. i, pt. 1. pp. 211-47, IS77. ' Nathorst, A. Ci., Koncl. Svcnska Vetonskaps-Akad. llandl., vol. 30, p. 6, 1897. • Nathorst. \. Ci.. Fossil jilanl* from Franz. Josef Land: Nonvc|{ian North Polar F.xped.. vol. 1, No. .1, 1900. THE JURASSIC FLORA OF CAPE LISBUBNE, ALASKA. 43 that of Cape Boheman and Siberia, appeai-s to liave nothino; in common with that of tho Ahis- kan locahty. Tho hirge and interesting Ikira o*' the ishmd of Bornliohn, whicli was Ihst described by Bartholin and later and more fullj^ by Moller',' was regarded l)y the latter as of Rhsetic or Liassic age. It is, as Seward has pointed out, "no doubt younger than the Rhsetic floras of Scania, Tonldn, and Franconia, and the number of Lower Oolite species which it includes would seem to favor the view that its affinities are rather wdth Jurassic than with Rhaetic floras of other regions." Tliis statement is, at least to some extent, borne out by the following species from Cape Lisburne wluch ar(^ found also in Bornholm: Podozamites lanceolatus, Crinl'go digitata, Phcenicopsis angustifolia, and PagiopJiyllnm hurrii. Turnmg now to the rich and wi'll-exploited Jurassic floras of England, we find Cmiiopteris TtymenophyUoides, G-inl-go digitata, and Zamites megapliyUus, of the Great Oolite (Bathonlan), in common with the Alaskan flora here discussed. Similar beds in Sutherland carry Coniopteris hymenopliyTlokles, Ginl-go digitata, and Elatides cunnfolin. The rich Jm-assic flora from Douglas County, Oreg., as worked up by Fontaine,- mcludcs the following species which appear to be present also m the Cape Lisburne region, though not all are listed here under the same names: Coniopteris Tiymenophylloides, Tliyrnoptiris inurrayana, Cladopllehis vaccensis, Podozamitis lanciolatus, P. I. latijolius, P. pulcJuUuN, Oinlgo digitata, and Phcenicopsis sp. From the composition and wide distribution of tliis flora as outlined above, the fhial conclusion is reached that the Corwin formation of the Cape Lisburne region is undoubtedly Jurassic in age, belonging either in the upper part of the Middle Jm^assic or Brown Jura, or the extreme lower portion of the Upper Jurassic or White Jura — that is to say, it is probably not older than the Bathonian and certainly not younger than the Oxfoidian. DISTRIBUTION OF JURASSIC FLORAS. GEOGRAPHIC RANGE. At lliis point it may be of general interest briefly to rcA-iew the character and geograpliic range of Jurassic floras, especially as developed in Ai'ctic and Antarctic regions. The wide area! distribution of Middle and Upper Jurassic floras has long been one of the mai'vels of plant distribution. The living flora, of course, affords many incU^adual examples of wide dis- tribution, such as those found throughout the Tropics of both hemispheres, and others, chiefl}' weeds, that have, largely through human agencies, spread widely over temperate lands, but altogether these plants foim but an insignificant part of the whole flora, whereas in Jm-assic time a large percentage of the whole flora was practically world-wide in its range. In Alaska well north of the Ai'ctic Circle is found the interestmg flora described in tliis paper. Although only a few fossil species are at present known to occur at Cape Lisburne, it is more than probable that the number would be greatly increased by careful examination, but the region is difllcult of access and we must possibly await the exploitation of its coal resources before adequate investigation of the flora will be made. The Jurassic flora has been found at a number of other localities in Alaska, the farthest north being a point between Icy Cape and WainwTight Inlet, about 180 miles northeast of Cape Lisburne. Another locality is near Nikolai, in the Copper River region, which has afTordcfl a single species of Sag('no[)teris that is closely related to a form from the Lower Oolite of Italy and has also been found in Oregon and California. Tins species came from a bed now known as the Kennicott formation,' where it was found in association with marine inverte- brates of T'ppcr Jurassic age. The largest representation of Jurassic plants in Alaska, aside from that of Cape Lisburne, is found on the north shore of Cook Inlet, where seven or eight species were obtained. These occur in the "Enochkin formation" of Stanton and Martin,* in ' MOUer, Hjalmar, Kont;!. Sven.ska Vctenskaps-Akad. Hand!., vol. 36, No. 6, 1903. 2 V. S. Geol. Survey Mon. 48, pp. 47-145, PLs. VI-XXXVIII, 1905. > U. S. Geol. Survey Hull. 448, pp. 31-43, 1911. < Oeol. Soc. America Hull., vol. 16, pp. .■897 et seq., 1905. 19205°— 14 2 44 CONTRIBUTIONS TO GENERAL GEOLOGY, 1913. intimate association with niarino shells reiiarded l)y tliese authors as the equivalent of the CalJovian of European standards, or the ujiper part of tlie Lower Oolite of English geologists. The last Alaskan locality to he mentioned is Ilerendeen Bay, which has yielded a single species of Pterophylhun. Tlie onlv other inij)ortant Nortii .Viueriean localities are those in Oregon and California, wliich together have afforded 101 forms. The collections from these localities are especially rich in forms of Cladophlebis, Tjeniopteris, Sagenopteris, Xilsonia, Pterophyllum, Ctenis, Ctenoi)hyllum, Podozamites, and Ginkgo. No less than 47 per cent of these species are found also in Jurassic beds in other parts of the world, notably in Alaska, eastern Siberia, and York- shire. England. The areas geographically nearest to the Alaskan localities are those of eastern Siberia. In 1876 Heer pubhshed liis first paper on the flora of these areas, which included material from Kajamundung, Fst-Bali, the upper Amur River, and Bureja. Tliis was supplemented in later years hy the study of further material from the original localities as well as from Lena Delta, etc. The total number of species finally aggregated about 100, and many of them hiave since been identified in mdely scattered parts of the world, the greatest number being common to the beds in Oregon and California and in 'i'orkshire, England. As a complete enumeration of the Jurassic floras of the world is impossible for lack of space in the present connection, the following list of loc-alities may be given as a partial indication of their wide range: United States: South Dakota. Wyoming. California. Oregon. Alaska: Cape LLsljume. Xpar ^Vain^v^ight Inlet. Nikolai. Cook Inlet. Ilerendocn Bay. England: Yorkshire. Scotland: SuUierland. Frajice: ifammers. Germany: I'ranco-.Swaljian area. -Xortheiustem area. Austria-Hungary : Steierdorf, Banat. Crojii-. Cialicia. Krakaii. Italy. Switzerland. Portugal. Sweden. Spitzbergen: Cape Boheman. Advent Bay. Cireen Harlmr King Karls Land. Franz Josef Land. Greenland : Cape Stewart. E;ist Coast. Siljeria: .Vmurland. Irkutsk. Lena Delta. Chosen (Korea). Japan . Caucasia. Turkestan. India: Culcli. Jalialpnr. China: Tyskyp-Tag. Honler Ihuni Desert. Austriilia. New Zealand. Graham Land: IIo])e Bay. The flora of Graham I^and, which has recently been careftiUy ehiboratc-d by Halle,' is worthy of more than passing notice. This flora comprises 01 forms dispersed among tlie larger groups as follows: Filical(>s 2.5, Cycadales 17, Coniferales Ifi, unknown .3. It is of interest to note that the (linkgoales, which form an important and variemi- sphere, are entirely absent from the Antarctic locality, as indeed tliey are from the tiontlwanas of India, and that Podozamites, which is abundant and variable in tiie north, is absent from the Hope Bay collection ann of living plants are animals, especially birds and mammals: water, especially streams and ocean currents: air currents; and, of course, human agencies. In considering the distribution of Jurassic plants we may at once eliminate mammals, which were in Jurassic time on the threshold of their development, and birds, which were represented by a single Icnown type (Archa?opteryx) that at best must have enjoyed but limited powei-s of flight. There remain, therefore, only air and water transportation to account for the distribution of Jui'assic plants. None of the plants is believed to have possessed any marked mechanism for wide and systematic dispersal. The ferns of the Jurassic period are believed to have been homosporous, which implies the production of vast numbers of spores of relatively short-lived vitality. A considerable number of hving ferns having spores of this character are widely distributed on both hemi- spheres. The male fern is an example; a single plant, according to Bower, may produce in one season 5,000,000 spores, which are particularly well adapted to wind dispersal. That ferns may pass over at least 25 miles of open water is shown by Treub, who found that on the island of Karakatau, which had been completely wrecked and sterilized by a volcanic outburst, within three years 12 species had already become reestablished. While the air currents may have been competent to accomplish this, the possibihty of other agencies, such as transportation by birds, ocean currents, or man, should not be ignored. The Equisetales were not an important element in the Jurassic flora, being mostly repre- sented by fragmentary material referred to Equisetum or Equisetites. Although many of the living species enjoy a wide distribution, little evidence is available as to their means of chspersal. The Cycadales are seed-bearing plants, the seeds being of small or mechum size. In the living species the seeds sink in fresli water and presumably would do the same in salt water. The length of time they would retain their vitality in salt water is problematical, though probably it would be very short. Their transportation for any great distance by water is open to (juestion. The Ginkgoales are very distinctly a waning type; in fact, they havi^ come almost to the vanishing point, for the single li\ing species is not believed to exist in a purely wild state. The identification of the early forms now commonly referred to the Ginkgoales is founded mainly on the foliage organs, and their seeds are not certainly known, but since the discovery of true Ginkgo in late Tiiassic or early Jurassic beds, and in practically its present form, the seeds have not infi-equently been found. These seeds, like those of the living species, are of large size. They have no special means for extended dispersal. In the living Coniferales there are certain minor devices for limited seed dispersal, such as variously winged seeds, but nothmg that is especially remarkable. The seeds of Jurassic Coniferales, so far as known, possessed no special devices for wider dissemination than that usually taking place on a land surface. AVENtTES OF DISPEKSAL. The data presenlccl in the foi'egoing paragraphs regarding [ho means for disp(>rsal woidd seem to indicate a practically continuous land connection between the several localities during Jurassic time. W'ith the possible exception of the ferns, whose spores might have been trans- 46 COXTEIBUTIONS TO GENERAL GEOLOGY, 1913. ported by air currents over vory coasidcriiblc distances of opoii water, none of the types appear to have possessed any niechanisni or device by which they could have spread so widely without a practically continuous land route. It is of course possible that masses of earth covered with livinsj vegetation — iloatinii islands, so called — may have been torn from the land by streams and carried intact for considerable distances into the sea, as similar '"islands" are now transported by the Amazon and other rivers, but the distance over which such masses would be elfective in colonization is relatively short. The striking similarity between the Jurassic floras of northwestern North America and eastern Siberia shows that the land connection between these locahties during Jurassic time must have been practically continuous. The known presence of Jurassic beds at ITerendeen Bay on the Aleutian Islands is at least a partial confirmation of the presence of this land britlge. If we may assume that the land adjacent to what is now Bering Sea was the center — or at least an important center — of distribution for the Jurassic floras, then, with conniiuni- cation established between the two continents, the way was open for a wide range over the northern heniisphere. The presence of a well-marked Jurassic flora in the Antarctic region goes far toward justifying the presumption of a former land connection to that region, for the present distance is so great as to preclude the reasonable probability that the flora could have reached there otherwise. PROBABLE CLIMATIC CONDITIONS. With the abundant ilata now available certain tentative conclusions may perhaps be drawn as to the climatic conditions which existed during the life of the Jurassic flora. There is no evidence that this flora was de])aupcrate or pinched as the result of adverse climate. On the contrary, the presence of large and luxuriant ferns, many of them tree ferns, and cycads, and of very abundant and large-sized leaves of Ginkgo, etc., especially in localities far north of the Arctic Circle, affords every evidence that the conditions of growth were favorable From the wide distribution of genera and species it appears that the conditions were also relatively uniform. In other words, there must have been abundant or sufficient moisture and a temperature that would permit the growth of such ]>lants. Knowledge of the probable moisture and temperature refiuirements of a flora now represented only by fossil remains must be gained l)y a study of the nearest related living flora. On this basis it seems safe to assume that the Jurassic flora indicates a moist, warm, pdssibly subtropical climate. THE FLORA. CoNioPTERis BL'REjENsis (Zalcssky) Scward. Plate V, figure 1. Coniopteris burejensis (Zalcsiiky) Seward, Jurassic plants from .XinurUind: Com. g^ol. M^m.. new sor., pt. SI, )). 22, PI. I, figs. 1-.5; PI. Ill, figs. 18-21. 1912. Dirksonia burcjcnsin Yjalesuky. Notes pal&)phytoIogiques: Com. g6oL IJulI., vol. 22. p. 192, PI. III. tigs. I-I; PI. iV. figs. 1-.5, 1904; Knowllon, in Collier, U. S. Geol. Survey Bull. 278. p. 29, 1906. Dicksonia n. sp., Knowllon, in Collier, loc. cit. Cladnphlebis rarcensis Ward, r-^ontaino. in Ward. U. S. Geol. Survey Mon. 48. p. 157. PI. XXXIX. figs. 7. 8, 1905. In 1904 Zalessky described a fruiting fern from Amurland under the name Dicksonia hurejensis, at the same time calling attention to its resemblance to Dicksonia coriacea Schenk,' from the Jurassic of Cliiiui, D. coiiciinin TIeer, from Annu'land, etc. In his recent work, cited above, Seward rcdescribed and religured the Zalessk}' spccimensj together with additional material recently procured, under the name Coniopteris burejensis, largely on the ground Ih.it the fossil is undoubtedly congeneric with Coniopteris hymenopliyJloidifi. If it is to be held that Coniopteris is congeneric with Dicksonia, then the former is untenabli*. for it dates from 1849, while Dicksonia was founded in ITSS. However, as there is some (l(ini)t as to their ■Schenk, A., JurassUrhe PSiinzen, in Richthufen\ ilun;i. v.il, 1, p. i')l. I'l, I.I, lit;. -', I'l. Ml. ni;s THE JURASSIC FLOK.\ OF CAPE LISBURXE, ALASKA. 47 generic idenlity it may bo well enough to retain the form under Coniopteris. It has usually been assumed that these plants belong to the family Cyatheaceac, but of this more will be said later. The salient features of Coniopteris hurejensis are described by Seward as follows: Frond bipiiinate or jirobably tripiiuiate; pinna" linear-lanceolate, attached to a comparativ'ely slender racliis along the margins of wliich the pinnae axes and the lamina of the basal pinnule on llie lower side of the pinna are decurrent. The pinnules may be oval and serrale. like those of C. hijmcnophylloides, or longer and narrower, the linear lamina being serrate, or more deeply dissected into small oval .segments; the latter form appears to be identical with that of some of the specimens described by Heer as Dicksonia gracilis and D. glehniana. In the larger examples the rachis is broader: the more widely separated pinnae give a more open habit to the leaf, in marked contrast to the more compact form. The venation is of the Sphenopteris type. In spite of Seward's elaborate explanation of the diversity in form and appearance of the sterile fronds referred to C. hurejensis, it is difficult to believe that all are correctly referable to a single species. The long, narrow pinnje with linear serrate laminte (cf. figs. 18 and 20 of Seward's PI. Ill) may very well be the sterile portions of the form that bore the fruitmg specimen, but it would seem that the longer, oval, slightly serrate pinnules such as are shown m his Plate III, figure 19, are too different to have come from the same species. However, the collection may have contained many specimens that were not figured and some of these may^ bridge the apparent differences. The fine fruitmg spccmien from Cape Lisburne shown in Plate V of the present paper is referred with much certauity to C. hurejensis. It is a frond of large size, beuig probaljly between .30 and 40 centimeters m length and at least 20 centimeters broad. It is tripinnatified, or quadripinnate. The maui racliis, which is over 3 millimeters in diameter and slightly zigzag, was evidently very stiff and rigid. The primary pmnis are remote, alternate, at irregular distances, and spreading at the tips, giving the frond a very open, spreadmg effect. The rachis is relatively strong and somewhat angled. The secondary pinnce are also alternate, sessile, lanceolate ui general outline, and cut into numerous linear, deeply cut pinnules. The sori are terminal on slightly reduced lammse. The sitigle specimen referred by Fontaine ' to Cladophlehis vaccensis Ward, a species first described from the Jurassic of Oregon, is at best very obscure. It does not have the nervation ascribed to C. vaccensis, though in the shape of the pinnules there is not much difference. It is undoubtedly the same as the form shown in Zalessky's Plate III, figures 1, la, and refigured by Seward in his Plq,te III, figure 19, and is to be referred to Coniopteris hurejensis. CoNioPTEUis IIY.MEXOPUYI.LOIDES (Broiigulart ) Seward. Plate V. figure 2. Coniopteris hymenophylloides iBrongniarl ) Seward. Juras.sic flora of the Yorkshire coa.st, p. 9,S, PI. XVI, figs, 4-6; PL XVII, figs. A. 6-8; PI. XX, figs. 1. 2: PI XXL figs. \-i. 3a. 4. 4a. 1900; Fontaine, in Ward. U. S. Geol. Survey Mon. 48, p. 59, PI. VIII. figs. l-:5, 190.5. Sphenopteris hymenophylloides Brougniarl. I'ii«lriiine. pp. 51. 198 [nomenj. 1828; Histoire des v^g^laux fossiles. ]>. 189, PI. I.VI, fig.s. 4, 4b, 1829. Adiantites amurensis Heer, Flora fcwsilis arciica, vol. 4, pt. 2. p. 94. PL XXI. figs. 6a, b; enlarged, figs, (i, '■, d. 1876. This is one of the most ahunthmt and widely distributed of Jurassic plants, having been repoi'ted from the Antarctic, many locaUties tlu-oughout the Ai-ctic, Siberia, China, Japan, Germany, France, England, and Oregon, and now from Alaska. As might be expected from tiie mnnber of students wlio liave liandl<>d it, it has been reported under several generic names (Sphenopteris, Thyrsopteris, Dicksonia, Adiantites, etc.), but it all seems conspecilic and is best included under the somewhat noncommittal name Coniopteris. This species is represented in the Cape Lisburne material })y the single piinia figured, but fortunately this fragment is excellently preserved and there can be no doubt as to (lie correctness of its identification. It is, for itistance, not to be distinguished from a specinuMi from the Jurassic of Yorkshire, England, figured by Seward.^ ' Fontaine, W. M., U. S. OeoL Sun-cy Mon. 48, p. 157, PI. XXXIX, figs. 7, 8, l!)0.'i. ' Seward, .\. C, Jurassic fiora of the Yorkshire coast, PI. XVI, fig. 6, 1«00. 48 CONXRIBUTIONS TO GENERAL GEOLOGY, 1913. Tho spocimon from Douglas County, Oreg., figured bv Foiitaim-,' hii-; probably been cor- rectly dcternuiu'd but is an indistinctly preserved fragment. The enlargements (figs. 2, 3) whicli purport to shovv^ the sori are, however, entirely incorrect, there being really no trace of the fruiting condition. Tho slightly involute marguis of tlic tips of t lie piimules were evidently mistaken by the artist for immature sori. A comparison of the specimen from Cape Lisburnc wit li Adiantites amurensis from iVmin-land us figured by Heer - shows them to be imiKiubtodly identical, and, as suggested by vSeward.^ there is uo doubt about referring the Amurland specimen to Ooniopteris JiymenophyUoidcs. Cladophlebis iuttoxi (nunker) Fontahic, Plate VI. figure 3. Cladophlebis huttoni (Dunker") Fontaine, in Ward, U. S. Geol. Survey Mod. 18. p. IGl. Pis. XLI-XLIII. 1R05; Knowltoii. in Collier, U. S. Geol. Survey Bull. 278. p. 29, 190(!. This species — one of the most abundant ferns in the Cape Lisbunie region — has l)een so fully described and illustrated by Fontaine m the publication above cited that it is unncces- sarj^ again to go over the ground. The one or two examples from the Collier collection are here figured simply for the purpose of showing that they are undoubtedly the same js the s|)ecimens identified by Fontaine fis ChdopJdebis huttoni (Dunker). Fnun the general shape and disposition of the j)iiina? and pumules, as well as the character of the nervation, there can be no (loul)1, it would seem, as to the correctness of referring these fronds to the genus Clado- phlebis, but wliether they are to be positively identified with Dunker's Neuropteris huttoni* from the Wealden of Hanover, is or may be quite a difl'ereut thmg. Fontame is very positive on this |)oint, sayhig: "This fern [Neuropteris huttoni] has an uncommon aspect, and it resem- bles so closely the ferns from Alaska that there can be no doubt that they belong to the same species," bxit of this 1 am not so sure. It appears that only one fragment of the Hanoverian plant was found, this being a portion of a very strong rachis about 5.5 centimeters long and two more or less perfect pinna^. Dunker's figure was copied by Scliunjier.'' who changed the name to Aldhopteris huttoni, and the origiital specmien was later studied and again figuretl by Schenk." Scheak's figure differs somewhat from the origmal one, showing apparently that the sjiecimen is really somewhat less ])erfect than would appear from Dunker's figiu'e. It seems not unlikely that this Hanoverian plant should be referred to Cladophlihis dentieuJata (Brongniart ) ; at least it seems strikingly similar to some that have been so referred — such, for instance, as one figured by Seward ' from tlie Jurassic of Yorkshire. The figure of the ty|>e specunen of Dunker's ])lant shows the i)mmv to be, as m Clado- phU'bis denticulata, sessile but not decuiTent on the mam rachis, whereas in the Alaskan fronds the |)lnna' are distinctly decurrcnt and, as Fontaine ])ohited out, there is an occasional pmnule on tlie main rachis between tiie insertions of the |)inna\ It was undoubtedly a very large fern. One specunen in the Dumars collection — shown in Plate XLI of Fontaine's report — is 32 centi- meters in length, and as it lacks both base and apex was probably twice as long when perfect. The main rachis in this example was more than 5 miliinu^ers thick. The secondary |)inna> have a tendency to be oj)posite on the rachis, though in the upper portion they may become somewhat alternate. They arise at an angle of about 45° and curve outward slightly so !?s to l)ecome apjjroximatcly at right angles to the rachis. In the lower and middle ])ortions of the frond the jjinna' are cut ileeply uito ovate-lanceolate, slightly falcate divisions or i)mnules. these beutg mainly entu-e, though some of them are {jrov-ided with a few low teetii; the pin- nules are for the most jmrt rather acute. The lower pumules of the lower ultimate puma' ' Fontaine, W. M., I'. S. Geol. Survey Mon. 48, PI. VUI, ng. 1, 1905. 5 Heer, Oswiild, Flora fo.ssilLs arctipa, vol. 4, pt. 2, PI. XXI, Dgs. Ba-d, 1X70. ' Seward, A. C, Com. r&I. Mi'm., new ser., pt. si, p. I'.l, 1912. • Dunker, W. 1). K. II., Monograph io der norddeutsclicn Wealdenbildung, p. '.i, IM. VIII, fig. 1. lS4ii. » Schimper, W. P., Trait(> de paleontologie viSgetale, vol. 1, p. 571), .\tlas, PI. XXXI, fig. 11), I,S6». • Sohenk, \., Palawntographica. vol. 19, p. 217, PI. X.XI.X |VI1I]. fig.s. 1, la, 1S71. ' Seward, A. C, Jurassic Horn o( the Vorksliire coast, PI. .\IV. Tig. 1, 190(1. THE JURASSIC FLORA OF CAPE USBURNE, ALASKA. 49 arc least uniteil. Toward the ends of the ultimate pinnae and m the ternnnal portions of the compound ends they are more and more united and pass into lobes and teeth, the size being at the same tmie diminished. The nervation is described bj^ Fontaine as follows: The midnerve goes off very obliquely and at aliout two-thirds the distance to the end of the pinnule splits up into branches, after the fashion of Cladophlebis, so that the plant is a well-marked type of that genus and in the absence of fructification must be placed in it. The lateral nerves, in proportion to the size of the pinnules, are quite slender. They are immersed in the leaf substance and are not conspicuous. They go off very ol^liquely and are forked one or more times. The lowest are the most copiously branched. The forking is notably low down on the nerve, so that the branches are unusually long. On the lower side of the base of the pinnules one or more lateral nerves go off from the main rachis. In the more separated pitnudes the lower lateral nerves curve away from the midnerve, but in the lobed and dentate forms the interior basal ones often curve inward toward it. On takmsi everything mto account it seems ]irobab]e that this fern should receive a new name, but it is so robust and abunihmt a form that it probajjly had a wide distribution hi Arctic lands, not bemg conhned to the vicinity of Cape Lisburne, and rather than give it a name which might possibly prove to be a synonym of some form known from less oomjilete material, I am permitting it to remam under the name given by Fontame. It is very much to be doubted, however, that this fern is identical with the Neuropteris huttoni of Dunker. ?Cladophlebis alata Fontaine. Plate V, figures 3, 4; Plate VI, figure 4. "iCladophlebis alata Fontaine, in Ward, U. S. Geol. Survey Mon. 48, p. 158. PI. XXXIX. figs. 9-11: PI. XL, 190.5. Onychiopsis psilotoides (Stokes and \\ebb) Ward, idem, p. 1.55, PI. XXXIX, figs. 3-6. Pecopteris r/enticulata Heer. Lesrjuereux. II. S. Xat. Mus. Proc, vol. 11, p. 32, 1888. It is with much hesitation that this s])ecies is permitted (o remaui under tlie designalioit given it by Fontauie in his review of the flora of Cape Lisburne, especiaUy in view of the fact that BeiTV ' has merged the origmal C. alata with C. browniana (Dunker) Seward, a common form in the Patuxent and .^Vrundel formations of Maryland and Virgiuiu. That it is identical with the Potomac forms is extremely doubtful, but that it is the same as the numerous speci- mens from Cape Lisburne that were so designated by Fontauie there can of course be no ques- tion. At first it was thought that this form represented the sterile foliage of Coniopteris hure- jensis, and tliis supposition may ultimately be verified. For instance, the jiortion of the sterile puma shown hi Plate \', figure 4, is ccrtaudy strikingly similar to the upper jihuia on the right- hand side of the figure* of C. burejensis shown m Plate V. They are of about the same size, have the linear puinules set at the same strict angle, and are cut nearly to the same degree. It is not to be denied that the sterile portions of the specimens here called CladopMebis aUita have a rather strikmg resemblance to Onychiopsis psilotoides (or mantelli, as it is more frequently called). Thus, the very large lower pmna showai in Plate V, figure 3, is similar ui general appearance to the figure given bj' Seward - of a specmien. of 0. mantelli from the English Wealden. Both these specimens show well the strict habit of the plants, and both lack the fuier details of the outlmcs of the ultimate divisions. In the iUaskan specimen the phmules are somewhat larger, but otherwise the difference is apparently not great. It was, of course, this general resemblance which induced Fontauie '' to identify certaui specunens in the earlier collections as Onychiopsis psilotoides, yet it is impossible to distuiguish these from a large niunber here referred to (Jladopidehis alata. For mstance, the puma showii in Plate V, figure 3, is not to be separated from figure 5 of Fontame's plate above cited. On the whole it seems best, pending the finduig of additional material, to leave this form under the name given it by Fontame, with the frank confession that such disposition is recog- nized as neither adequate nor final. ' Berry, E. W., Maryland Geol. Survey, Lower Cretac»ous, p, 24:j, 1!I12. » Seward, A. C., Fos.sil plants of the Wealden, pt. 1, 1'l. II, fig. 1, 1894. ' Fontaine, W. \L, U. S. Geol. Survey Mon. 48, p. 155, PI. XXXIX, figs. »-6, 1905. 50 CONTRIBUTIONS TO q.ENEKAL UEOLOGV, 1913. Equisetum collieri n. sp. Plate V. (igure 5. Stem vorv little flattonod or distorted, about 6 or 7 millimotors in diameter and about 5.5 centimeters loufi between the nodes, slightly swollen in the nodal rejrion, and with about eight relatively very strong longitudinal ribs and corresponding channels; sheath very short, appressed; teeth aj)parently of the same number as the ridges, about 12 millimeters in length, slender and sharply acuminate at apex, each hing closely appressed in a groove; tubercles, or enlarged subterranean portions, present at the lower node. This species is based on the only example noted in the Collier collections and has been named for the collector. As may be seen, it has been little flattened or otherwise distorted and may be viewed nearly in its entirety. It is chiefly remarkable for the vexy prominent ribs and corre- sponding channels, and the short sheath witli the long, slender acuminate teeth closely appressed in the tlepressions. I have verv little doubt that this is the same as the form from Cape Boheman, Spitzbergen, described by Heer ' under tlie name Equisetum i-uguJosum. though the present form is better preserved and admits of a fuller description of the essential characters. The size and the jiromi- nent ribs arc evidently similar in both, though the Spitzbergen specimen is not swollen in the nodal region, and of course the character of the teeth can not be made out. Rather than make a doubtful identification, however, I have placed the Alaska specimen under a different name. This species is also similar to the specimen of Equisetum burejense from Amurland shown in one of the figures given by Heer.- This figure shows a porticm of a stem with parts of two nodes and an attached "tuber," as well as several scars, whence apparently other "tubers" have been broken. The figure of E. collieri shows the presence of a "tuber" of similar size and ap])earance, at least so far as can be made out, at the lower node. The size of the stem is similar in the two forms, though E. burejense is not swollen in the nodal region nor are the longitudiuiU ridges so prominent. Seward,^ in commenting on Equisetum burejense, says: "These incomplete specimens may be tubers of Eciuisetites, but they are hardly worthy of a specific name." This attitude of mind in dealing with obscure oi biologically uncertain forms is not the right one, in my opinion, for if a plant is sufficiently well characterized to be used as a stratigrajiliic mark its usefulness is increased by giving it a definite name that can be employed for reference, whether it is bio- logically allocated or not. .Vathorst,^ who reviewed Heer's Cape Boheman material, reduced not only his Equisetum rugulosum but also E. bunburyanum Heer anil Phytothcca latiralis'. Heer to f^quisetites sp., remarking that they are too poorly preserved and doubtful to be maintained. The fine trans- verse lines on Equisetum rugulosum spoken of by Heer are, according to Xathorst, only checks in the carbonaceous covering. Be this as it may, there does not appear to be any doubt as to the correctness of referring the present Alaska form to Equisetum. OtozaiMites oiganteus Thomas. Plate VI, figure 2. OlozamiUs gifianteus Thoma.s, Jurassic llora of Kamenka: Com. p;6)l. M^ni., new ser.. pt. 71, p. ,H4, PI. VI. ligs. I, 2, Hill. The single example figured is the only s])ecimen of this species that has been foimd. It consists of a ])ortion of the rachis about 4 centimeters in lengtli and the basal portions of tliree leaflets, only imc nf wliicli, liowever. is anywlicrc near perfect. This most j)erfect Icillct is I." millimeters witic and is preserved for a length of about 4.5 centimeters and was presumably ' TTecr, Oswald, Flora fos,silis arctica, vol. 4, pt. 1, p. 32, PI. VI, fig. 19, 1876. '- IdiTn, pt. 2, p. !i<", PI. -XXII, ng. .S, l,S76. ' Seward, \. C, Juras.sU' plants from Amurland: Com. g&>l. M^m., new ser., pt. 81, p. 20, 1U12. < .Vatliorst, .\. 0.,Zur mewzoischen Flora Spitzbergens: Kongl. Svenska Vetenskaps-Akad. Ilandl., vol. :iO, p. I2, isii;. THE JURASSIC FLORA OF CAPE LISBUKNE, ALASKA. 51 some 7 or 8 centimeters in Jengtli when li\'inij. The base is phiinly lieurt-shaped, with the upper side slightly the longer and ajiparently a little overlapxnng the rachis; the point of attach- ment is approximately in the center of the leaflet. The margins of the leaflet are comj^letely preserved only near the base, but so far as can be made out little narrowing is apparent. The nervation all arises at the point of attachment and thence ra(hates out with occasional forking to accommodate the enlarged area reached. The type locahty for Otozamites giganteus is Kamenka, in tlie district of Izium, in beds of Bathonian age ( = upper part of iliddle Jurassic or Brown Jura), and until the present record the species had not been found elsewhere. Zamites meoaphyllus (Phillips) Seward. Plate VII, figure 1. Zamites megaphyllus (Phillips) Seward, .Jurassic flora, pt. 2. PI, X, figs. 4. 5; PI. XI I, fit.'s. 1. :i-.'i, 1904. ralst'ozamid nugaphijUa Phillips, Geology of Oxford, p. 169, Diag, XXX, fig. (i, 1871. Irites alashaiia Lesquereux, U. S. Nat. Mus. Proc, vol. 10, p. 36, 1887. Baiera palmata Heer, Lesquereux, idem, vol. 11, p. 31, PI. XVI, flgs. 4, .i, 1888. Nageiopsis longi/olia Fontaine, in Ward, U. S. Geol. Survey Men. 48, p. 171. PI. XLV, figs. 1-5, 1905. Podozamites grandifoiius Fontaine?, idem, p. 167, PI. XLIV, fig, 1. Leaflets coriaceous in te.xture, long, narrow, strap-shaped, slightly falcate, abruptly rounded at base, narrowed from or below the middle to a long, slenderly acuminate apex: margin perfectly entu'e: attachment unknown but probably sessile by the narrowed ])ase; nerves dis- tinct, parallel, not forking unless at base (which has not been clearly seen), 20 or 25 in number, each separated by about 10 thin, very delicate intermediate veins. This species is represented by nearly twenty examples, none of which is absolutely com- plete, as all lack the e.xtreme base showing the point of attachment. The character of the extreme tip, however, is well shown in several specimens. The ma.ximum length observed is about 18 centimeters and the width 2.5 to nearly .3 centimeters. At least two of the specimens show that the base is becoming rounded to the pomt of attachment, but unfortunately none is quite clear at this place. The character of the nerves, both the larger and the fine intermediate ones, Is plainly discernible in most of the specimens; they are fully described above. It was at first my mtention to describe this as a new species of Zamites, but on further consideration I found it impossible to distinguish the form from Zamites megaphyllus (Phillips), as described and figured by Seward ' from the Great Oolite (Bathonian) of Stonesfield, England. Although Seward states that the English material consists almost entu-ely of detached leaflets, he was enabled to give the following diagnosis: Frond pinnate, pinnae attached to the rachis at a wide angle, reaching a length of more than 30 centimeters and a breadth of over 3 centimeters; linear in form, attached by a slightly contracted concave basal surface, which is somewhat thickened: the lamina tapers gradually to an elongated acuminate apex, frequently falcate near the tip. Veins numerous and parallel, converging slightly toward the base and apex of the pinnse. This diagnosis, it will be obsisrved, agrees absolutely with that drawn from the Alaska specimens. In the largest example figured by Seward,- which was 4 centimeters wide, the "lamma is traversed by inimerous parallel veins between which, as shown in the drawing, occur fuier longitudinal lines." In this particular, therefore, the specimens from Cape Lisburne agree with tlie English species and apparently there can be no doubt as to their being correctly referred to it. There has been much tmcertainty as to the generic reference for these fine leaflets. The first examples of this form were obtained at the C'orwin mine, in the Cape Lisl)urne region, about 1885, by Henry D. Woolfe. These were studied by Lesquereux, who named them Ifites alasl-ana on account of their presimied resemblance to leaves of the living Iris. He described them as follows: "Leaves thicklsh, luiear-lanceolato, tubuloso at apex, narrowed to the base, falcate, equinerved; median nerve obsolete; the lateral broad, eqinil." He also adds that the "nerves are about 1 miUimeter in width [apart], not very prominent, equal, not ' Seward, A, C, Juriissio rtora, pt. 2, p. Ill, liXM. 2 Idem, I'l. X, flK. 1. 52 CONTRIBUTIONS TO GENERAL GEOLOGY, 1913. separaKMl by intenncdialt' vciiilots, very (listiiul. " I have oxaiiiiiicd these sperimeiis. which are preserved in tlic United States National Museum, and find them huHsthitruishahle from tlie Collier specimens, <>x(('pt in si/.e. Tlio specimtnis of " Irites alashina," with additional examples colleclecl at the same locality by II. 1). Dimiars in ISDO, were studied by Fontaine and referred to Xagcinpsix longifoVia Fontaine, a veiy a])ui\dant form in the Patuxent formation of Viren my ojtinion. and in liiis I am supported by E. W. Berry.' that these specimens from Cape l.isburne have absolutely nolliing to do with Najjeiopsis nor of coui-se with Irites. They liave Ix'cn compared carefully with the tjqje aiul typical nnite- rial of Nageiopsis longifolia Fontaine, and they are not the same. It is believed that they are not even congeneric .- I am also refei-i-ing to Zamites megaphyUus the specimens that Ijcsquereux ' referred to Baiera palmata Ilcer and that Fontaine later referred with (juestion to Podozamites grandifolius Fontaine. Both these authors fell into the error of regarding these leaves bottom side up — ■ that is, as nuiy be seen on referraig to Lesquereux"s figure 4, the part figured as the base is in reality tiie apex. Fontaine,' in speaking of these specimens, expressed d(iul)t as to their afhnity but linally rc^ferred them to his Podozamites gmndifoHufi, which is now |)laced under Cteitopsis htt'ifoJia (Fontaine) Berry, ° a rather rare species of the Patuxent formation of Mi-ginia. Although these leaflets are if anything even larger than the Collier specimens here figured, thev do not difTer othiMwise. at least so far as can be matle out from their somewhat fragmentary condition. Phcenicopsis speciosa Heer. Plato VIII. figures 2-1. Phwnicopm speciosa Heer. Flora fcssilis ar(tiveral fragments that appear certauily to belong to Phani- copsis angustifolm . Whether this s]>ecies Is really dlstuict or Ls referable to P. speciosa, as Seward " sugg(>sts, must be left to the future to determme. The present specimens are to be identified witli P. angustifolia but throw no light on the (piestion of their identity willi P. speciosa. Podozamites lanceolatus (Lindley and llutton) Fr. Braun. Podozamites lanccolatus ( Liiulley and Ifuttoii) Fr. Braun (non Knimons), V('rzi'i(hnis.s dor in dor Kreis-Naturalien- Sammlung zu Bayrculli befindlichen Petrolacteii. p. 100. It<40; Hoor. Flora h)s.sili.s arotica. vol. 4, pt. 1, p. 3.5, PI. VII. figs. 1-7,1876; idem, pt. 2, p. 106, IM .\.\ 1 1 1, figs. k-.4a-c; PI X.XVI. ligs. 2-11); PL XX VII. figs. 1-8, 1876. The typical form of this variable type is rejiresenled by only a few fragments of rather large leaves that are too poor to ligui'e. ' Maryland Geol. .Surve.v. Lower Cretaceous, p. 383, 19U. * Since the above was WTJtlen Ilamshaw Thoiuas hjis published a short pap(?r (Some now and rare Jura.ssic plants from Yorkshire: Cambridge Philos. Soe. Proc., vol. 17, pp. 2.'>t>-262, Pis. VI, VII, iyi:i) in which hehiLsdescriliedanewtj-peofginkgodian leaf under the name EretmophyUura. In dLscu.ssing the relatioiLship of this new form Thomas suggests the possibility that these specimens, referred by Fontaine to Xagehpsui longihtia, may really Im referable to his Eretmophyllum. Continuing, he .says: "Fontaine's nguro h might po.ssibly bo an Eretmophyllum leaf figured upside down, anil the shape of the other fragments, thin distant veins almost parallel but sometimes forking, present.s. some points of similarity.'* A comparison of tbi'siMH-imons studied by Fontaine, as well as the Collier specimens hero figured, shows that this suggest ion is not witliont weight. This may account for the fact that the leaves or leaflets are always isolated, and further they may have boon improjHirly oriented. Uowevcr, until further proof is forthcoming, it seems as well to leave them under Zamites. " U's.|uereu-\, Leo, C. S. Nat. Mus. Proc., vol. 11, PI. XVI, figs. I, .i, p. 31, 18S.S. « Fontaine, W. M., U. S. (iool. Survey Mon. 4.s, p. 167, lOtt). ^ Berry, E. W., Maryland (ieol. Survey, Lower Cretaceous, p. 34i), 1011. •Seward, A. C. Jurassic plants from Amurland; Com. gtfol. Mc'm., new ser., pt. si, p. 21. 1912. THE JUKASSIC FLOKA OF CAPE LISBUKNE, ALASKA. 53 PODOZAMITES I.AXCEOLATUS EICHWALDI (SchilUpei) Ilecr. Plate V. ligiire 0: Plate VI. iigiire 5. part. Podozamites lanceolatt(s eichwaldi (Sehimper) Heer, Flora fossilis arclk-a. vol. 4, pt. l', p. 109. PI. XXIII. fig. 4; PI. XXVI, figs. 2, 3, 9; PI. XXVII, figs. 1, oc, 1870; Xathorst, Zur mesozoisrheii Flora Spitzbergens: Kongl. Svenska Vetenskaps-Akad. Handl., vol. 30, p, 13, PI. I. fig. .5. 1897. Podozamites eichwaldi ScbLmper, Traitg de pal&ntologie \eg<''tale, vol. 2, p. IGO. 1870: Ileer. Mora )'o.s.>iilis arciica. vol. 4. pt. 1, p. 36, PI. VL fig. 22c; PI. VII, fig. 7c; PI. VIII, figs. 1^, 187(5. Podozamites lanceolatus latifoliits (Schenk) Heer. Knowlton, in Collier, U. S. Geol. Surxey Bull. 278. p. 29, I90(;. This fonn is very abundant and excellently well preserved in the Collier collections, and Heer also speaks of it as being an abundant form in the sandstones at Cape Boheman, Spitz- bergen. At fii'st Heer described it with full specific rank, but later he inclined to regard it as merely a variety of the omnipresent P. lanceolatus, and this is the view taken by Nathoi-st, who restudied Heer's specimens together with much additional material. Nathorst states that three forms of P. lanceolatus are jjresent at Cape Boheman — P. lanceolatus genuinus, P. I. elcli- ^valdi, and P. I. ovalis. It is quite possible that a large series might show that these forms so intergrade as to make it unsatisfactory to attempt to draw any sharp lines between them, but in the present collection they appear very distinct. For stratigraphic purposes the variety eichwaldi is certainly well marked, a fact which is of interest m the j^resent comiection as tend- ing to connect the Cape Lisburne region with other undoubted Jurassic localities. Ei.ATiDES ciRViFOEA (Duuker) Xatliorst. Plate VIII. figure 1. Elalides atrvifolia (Dunker) Xatliorst , Zur mesozoischen Flora Spitzbergens: Kongl. Svenska Vetenskaps-Akad . Hand I vol. 30. p. 35, PI. I, figs. 25-27; PI. II. figs, 3-6; PI. IV, figs, 1-18; PL VI, figs, 6-8, 1897. Lycojtoditrs cvnifolius Dunker. Monographie der norddeutschen Wealdenbildung, p, 20, PL VII. lii;. 9. ],N4(i. The single fragmentary^ example figured is all that was noted of this sjiecies. Pagiophyllum kurrii. (Ponifli '■^ihimper, Plate VI, figure 1. Paginphillwn kurrii (Pomel') Sehimper, Trailede paleontologie vegetale, vol. 2, p, 250, 1872; MoUer, Bornholms fossila Flora, Gj-mnospermer: Kongl, Svenska Vetenskaps-Akad, Handl., vol. 36, p. 31, PL V, figs. 10-12, 1903. Araumria pereffrina p. p., Kurr, Beiinige zur fos.silen Flora der Juraformation AVurttembergs, p, 9, PL I, fig, 1. 1846, iloreauia kuhrii Pomel, Materiaux pour servir a la flore fossile Jurassique de la France, p, 21, 1849, This species, described originally from the Jurassic of Wurttemberg, was found by Moller at Bornholm in beds regarded as either Rhsetic or Liassic. Whether Moller has been correct in determuimg the Bornholm plants as identical with Pagiophyllum kurrii need not be discussed at this time, but it is certain that the specimens so figured and named by him are not to be distinguished from the Cape Lisburne example here figured. For instance, MoUer's Plate V, figure 12, shows a short branchlet with broad, rather obtuse leaves that is certauily the same as the specimen from Cape Lisburne. On the same piece of matrLx and lying very close to the branchlet from the CoUier collection is the apical portion of another branchlet which maj' or may not represent a very unmature cone. It is not well preserved and hence can not be matle out with certainty. Just below the "cone" are two or three leaves of the same size and appearance as those on the adjacent branchlet; below these the leaves l)ccome crowded and a|)])arently narrower and shorter. It is. on the whole. j)robable that this is merely a growing tip in which the leaves are not fully deA'eloped. 54 COXTKIBUTIONS TO GENERAL GEOLOCJV, lOKi. PaGIOPIIYI.LUM .STEENSTIUPI Billt llolilW Pagiophyllum steenslrupi Barlholin, Noglc i dpn Imrnlioliiiskc .luraloriiirtlion lorckummciulo Planteforstoninger, p. 10), PI. V. figs. fi-S; PI. VI, figs. 1, 2. 4. 1894; Mollcr, Bornliolms fdssila Flora. Ciymii.is|)crmer: Kongl. Sveuska Veten- skaps-Akad. Ilaiull.. voL 36. p. 33. PI. VI. fig-s. 1-3. 1903. The Cn\)o Ijisburnc material contains two minute fragments tliat appear to be the same as the tips of bramhlets such as are showTi in Plate VI, figure 3, of Moller's paper, cited above, but they are so small and uncertain as to make their identification more or less questionable. These s])cciraens also suggest Stacht/otaxus sej>fenfrionalis (Ag.) Xathorst, as figured b}^ MoUer,' but there is not enough preserved to identify them certainly with that species. PiTYOPiiYi.urM xouDEXSKiOLDi (Heer) Seward. Pitijophi/llum nordenskioliH (,Heer) Seward. .lura.siiic )ilanl.-i t'rum Amurland: ('dm. gi'ml. Mom., now ser.. pt. 81. p. 30, " PI. II. fig. 17; PI. HI. fig. 22, 1911'. Pinm nordcnsl-ioMi Ileer, Flora fossilis arclita, vol. 4, pt. 1, p. 4b. PI. IX, figs. 1-6, 1S76; idem, pT. 2, pp. 76, 117. PI. IV. fig. 8c; PI. XX. fig. 4. a. b; PI. XXVII. fig. 9a; PI. XXVIII. fig. 4. 1876. This form is represented in the present material by several small fragments whicli are about 3 millimeters ui width and 2 or 3 centimeters in length, evidently from the middle portion of the leaves. They have a smgle very strong median rib antl show distincth' the peculiar transverse ^Tinkling so well known in leaves of this tvpe. One fragment appeare to show the presence of the longituduial groove in the middle of the lamina that is regardeil by Nathorst as so char- acteristic of this species, though the others m close proximity to it ilo not. It is probable, as Nathorst has suggested, that the transverse wrinkling is in the. main a ])henomenon of desicca- tion, though it was doubtless more or less connected with some structural peculiarity. As Seward - has very well said, it Ls extremely difficult, if not impos3il)le. satisfactorily to distmgulsh between many of the Rha^tic and Jurassic leaves that have been described from time to time under the name Pityophyllum. Thus I can see no marked distinction between what is here called P. nordcnsl-idhll and. P. staratschini (Heer) Nathorst,^ from Advent Bay, Spitz- bergen. It also agrees closely witli Tazites cf. gramineus (Heer) as figured by Xathorst * from Franz Josef T.,and. Seward '' has suggested that the leaves from the Jiu'assic of Oregon referred bj- Fontaine" to Nihonia- parvuh. {Txniopienfi parvuJa Heer) are to be regarded as belonguig to Pityophyllum, but this can hardly be so, for they arc mucli larger than any usuallj^ referred to Pityophvlhun, and moreover they have a lateral nervation exactly as figured by Heer uniler Tsen uipterits parvula. FlELDEM.V XOHDEXSKIOLDI Xat.llorst. Plalo Vll, figiire2. Fieldenia nordenakioldi Nathorst. Zur mesozoischen I'lora S])ilzl)tM-gens: Kongl. Sveuska Vetenskaps-.\kad. Haiidl.. vol. 30, p. .56. PI. HI. figs. 16-27, 1897. In the material from Cape Lisbiune i find several more or less well preserved leaves that I am unable to distinguish from Xathorst's species, which comes fnini the ri)per Jiu-assic of Advent Bav, Spitzbergen. Tiie example, figin-ed is nearly perfect, except that the nervatitm is rather bidistinct, though careful scrutiny discloses the presence of about eight thin, parallel nerves. The point of the leaf is obtuse and mundiil. the basal portion is narrowed to the point of attachment, and on the whole this leaf is absolutely indistinguishable from that sliown in figure 17 of Xathorst's Plate HI. As Xathorst ha.s pointed out, it is diflicult, if not impossible, to distinguish between the present species and what Heer' has called Podozamites ensiformis and /'. cuspiformi^ from the Irkutsk, eastern Siberia. ' Op. tit., PI. V, flg. 7. I Seward, A. C, Jurassic plants from .Amurland: Com. Rfel. Mfm., new scr., pt. M, p. 30, 1912. ' Nathorst, A. O., Zur mesojoisilicn Flora Spitzbcrgens: KohrI. Svonska \e|pnskaps-.\ka