A REVISION OF THE FOSSIL FERNS FROM THE POTOMACGROUP WHICH HAVE BEEN REFERRED TO THE GENERACLADOPHLEBIS AND THYRSOPTERIS.
By Edward W. Berry,Of the Johns Hopkins University , Baltimore.
The present paper is the fourth and last of a series of revisions ofthe more important genera of fossil plants from the Potomac groupin Maryland and Virginia.^ The following genera have been discussedin previous numbers of the Proceedings : Nageiopsis, AcrosticJiopteris,Taeniopteris, Nilsonia, Sapindopsis, Sequoia, Athrotaxopsis, Sphe-nolepis, Ahietites, Pinus, CepJialotaxopsis, BracJiyphyllum, and Wid-dringtonites.With the appearance of the present communication all of the largergenera including those most in need of revision will have been treated.The remainder of the flora, numbering about one hundred species, willbe fully described and illustrated in a Monograph of the Lower Creta-ceous which will appear under the auspices of the Maryland GeologicalSurvey.The fern genus Cladoplilebis, wliich is discussed in the first part ofthis paper, is an important cosmopolitan type in the Lower Cretaceous,a type which is an undiminished survival from the older Mesozoic.A large number of species have been described, both in this countryand elsewhere. These ferns are abundant and important elementsin the Potomac flora. The remains represent for the most partspecies of considerable size. The usual difficulties in dealing withfossil fragments of large and somewhat variable (in time and space)fronds have resulted in the previous description of many more speciesthan the evidence warranted, a result equally confusing to both thebotanist and the geologist.The numerous species of Thyrsopteris recorded in the Uteraturefrom the Maryland-Virginia area are treated in the second part ofiThe previous papers are: (1) A revision of the fossil plants of the genus Nageiopsis of Fontaine,Proc. U. S. Nat. Mus., vol. 38, 1910, pp. 185-195. (2) A revision of the fossil plants of the generaAcrostichopteris, Taeniopteris, Nilsonia, and Sapindopsis from the Potomac group, Proc. U. S. Nat.Mus., vol. 3s, 1910, pp. 625-644. (3) A revision of several genera of Gymnospermous plants from thePotomac group in Maryland and Virginia, Proc. U. S. Nat. Mus., vol. 41, 1911, pp. 289-318.Proceedings U. S. National Museum, Vol. 41, No. 1862. 307
308 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 41.the paper in a markedly different manner from what has previouslybeen customary and are considered as representing the polypodi-aceous genus OnycTiiopsis of Yokoyama.THE GENUS CLADOPHLEBIS.The genus CladopJilebis is essentially a form-genus which is restrictedat the present time to include only certain fern remains of Mesozoicage, although this type of frond is practically identical with those ofsome Paleozoic genera, as for example Pecopteris, and it can also beclosely matched by a variety of Tertiary and living ferns.CladopJilehis was proposed by Brongniart in 1849 - for those specieswliich formed the section Pecopteris neuropteroides in his ''Histoiredes vegetaux fossiles" which he regarded as transitional betweenPecopteris and Neuropteris. Certain of their characters were men-tioned but no formal diagnosis was attempted. Saporta was per-haps the first to define the genus with precision.^Scliimper in 1874 gives a somewhat amplified diagnosis.^ Latertliis author* abandons CladopJilehis in the behef that the fertUespecimens described by Heer justify the reference of these forms tothe modern genus Asplenium.The most recent diagnosis is that by Seward, wliich may appro-priately be quoted for the American Cretaceous forms:Fronds pinnately divided, pinnee spreading, lobes or pinnules attached by the entirebase or slightly auriculate, acuminate, or obtuse, occasionally dentate, especially atthe apex, not rarely subfalcately curved upwards, midrib strong at base, and towardsthe summit dissolving into branches, secondary veins given off at a more or less acuteangle, dichotomous a little above the base, and repeatedly dichotomous.^Much difference of opinion has prevailed regarding the unity andthe systematic position of the genus, Saporta ** having long agopointed out that Brongniart's species had nothing in common withthose of the Mesozoic and that the Liassic and Oolitic forms, thosewhich the former author was discussing, give evidence of commoncharacters. At the present time there is still lacking evidence fromsuch fructified remains as have been discovered of close relationshipbetween all of the various species of CladopJilehis. Thus Heer dis-covered in the Siberian Jurassic, fragments of the CladopJilehiswJiithyensis type with soral characters which he compared with thoseof the subgenus Diplazium of Asplenium'' and Schenk has figuredfertile pinnules of the same type in the case of the alHed Asplenites
1 Tableau, p. 25.2 Saporta, Pal. France, ser. 2, V6g6taux, Plantes Jurass., vol. 1, 1873, pp. 298, 299.3 Schimper, Pal. V6g6t.,vol. 3, 1874, p. 503.
* Schimper in Zittel's Handbuch der Palaeontologie, Abth. 1, 1890, pp. 99, 100.
' Seward, Wealden Flora, pt. 1, 1894, p. 88.6 Saporta, Pal. France, ser. 2, V6g6taux, Plantes Jurass., vol. 4, 1888, p. 357.
' Heer, Flora foss. Arct., vol. 4, 1877, p. 38, pi. 21, figs. 3, 4.
NO. 1862. FOSSIL PERM'S FROM THE POTOMAC GROUP?BERRY. 309
roesserti} Certain specimens of the Jurassic species CladojpTiIehislohifolia show that the sporangia in tliis species were apparentlyborne in semicircular pocket-hks depressions on the edges of thefertile segments^ wliile the fructifications of CladojMehis denticulataare in the form of narrow oblong sori parallel wdth tne secondaryveins and are compared by Seward^ with the modern forms Aspleniumlugubre and Phegopteris decussata.In liis latest utterance on tliis subject Professor Seward says that
''there are fairly good grounds for the assertion that some at least ofthe fronds described under tliis name are those of OsmundaceaB." *Zeiller has recently described a species from the Wealden of Peruwliicli he considers identical with, or very close to, Cladophlehishronmiana in which the sporangia are biseriate, oval, and annulate asin the Scliizaeacea?. These are said to be very Uke those of theJurassic genus Klukia of Raciborski.^In the Potomac flora? we find that 14 so-caUed species of AspidiumSwartz (Dryopteris Adanson), mostly fertile fronds, were describedby Fontaine in 1890. These showed mostly large elhptical or reni-forni sori in rows on each side of the midvein and located generallyon the distal branch of a furcate vein and usually wanting in theapical part of the pinnule. These were compared by tliis author withmodern species of Aspidium, Cystopteris, Polystichum, and Didy-moclilaena. The preservation is not of the best, the matrix beingcoarse, and Fontaine's figures are largely ideahzed. It has seemedremarkable that the fronds of Dryopteris in the Potomac beds werealmost always fertile, wliile those of Cladophlehis, in intimate associ-ation with them, were invariably sterile.By careful comparison it has been possible to correlate the fertilespecimens described as Dryopteris \vitli the sterile Cladophlehis fronds ofthe same species in five of the types which are represented in the Poto-mac flora by sterile and fertile fronds, and the presumption is strong,although unverified, that the remaining Dryopteris forms representfertile fronds of Cladophlehis. Wliile the foregoing facts are not inunison in regard to the systematic position of Cladophlehis, they allpoint to the inclusion of the following American species in the familyPolypodiaceae or in what represented this family in Lower Cretaceoustimes, and cast doubt upon Raciborski's suggestion that Cladophlehisdenticulata and other species of the same genus were the sterile fronds*of osmundaceous ferns. It is quite possible that ferns of more thanone subfamily of the Polypodiaceae, or indeed of other famihes, are
1 Schenk, Flora Foss., Grenz. Keup. Lias, 1867, p. 51, pi. 7, figs. 7, 7a.2 Seward, Jurassic Flora, pt. 1, 1900, p. 23.3 Idem, p. 141.
? Seward, Fossil Plants, vol. 2, 1910, p. 345.6 ZeiUer, Comptes Rendus, vol. 150, 1910, p. 1488.
? Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, pp. 93-104.
310 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.41.included among the various described species of CladopMehis . It needbut be remembered how many unrelated modern ferns liave frondsof the Clado'phlebis type, as for example certain species of AlsopMla,Asplenium, Cyathea, Dryoyteris, Gleichenia, Onoclea, Osmunda,Pteris, Polypodium, etc., to cast doubt upon the botanical affinityof Cladoplilehis species unless these are attested by a considerablebody of evidence. It is believed, however, that the Potomac speciesare all to be included in the subfamily Aspidieae, or as it is more prop-erly known, Dryopterideae ; and because of this, and also becausetheir actual identity with the modern genus Dryopteris or in fact withany of the modern genera in tliis subfamily is extremely questionable,it has seemed wiser to use the more general name CladopTdehis insteadof using Dryopteris where the sterile and fertile fronds have beencorrelated.A large number of species of Cladoplilebis have been described, twospecies, according to Arber, occurring in the Permo-Carboniferous ofIndia. The genus appears in force in the Keuper and Khaetic withmore than a dozen recorded species. Over a score are recorded duringthe Jurassic, certain types such as dadopTilehis denticulata apparentlybecoming world wide in their distribution. For the Lower CretaceousSaporta has founded a large number of species based upon Portu-guese material and Fontaine has instituted a still larger number ofAmerican species. From the Potomac beds of Maryland and Virginiathe latter author recorded 23 different species besides several varietiesof Cladophlehis, altogether losing sight of variations and changes dueto age or to position of the fossils with regard to the frond as a whole,as well as changes due to the direct action of the environment. Thesespecies were often based upon such insufficient material that it becomesalmost impossible to deal with them with any degree of assurance.In considering all of the more representative material, and includingwith it all of the forms recorded from Maryland, w^e have a total of8 species, and these 8 species include remains which were the basis for23 of Fontaine's species and varieties of Cladophlehis, 6 of his speciesof Dryopteris and 9 of his species of Pecopteris.CLADOPHLEBIS ALBERTSII (Dunker) Brongniart.Neuropteris albcrtsii Dunker, Monogr. Norddeutsch. Wealdenbildung, 1846, p. 8,pi. 7, figs. 6, 6a.Alethopteris albertsii Schimper, Pal. Veg^t, vol. 1, 1869, p. 570.Pecopteris whitbiensis Trautschold, Nouv. Mem. Soc. Nat. Moscou, vol. 13, 1870,p. 27, pi. 19, fig. 2.Pteris ? albertsii Heer, Flora foss. Arct., vol. 6, Abth. 2, 1882, p. 29, pi. 16,figs. 5, 6; pi. 28, figs. 1-3; pi. 46, figs. 22-24.Pteris albertini Velenovsky, Abh. k. bohm. Ges. Wiss., vol. 2, 1888, p. 15, pi. 4,figs. 6-10 (not fig. 5).Cladophlebis albertsii Brongniart, Tableau, 1849, p. 107.?Seward, WealdenFlora, pt. 1, 1894, p. 91, pi. 8.
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROVP?BERRY. 311Cladophlehis inclinata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 76,pi. 10, figa. 3, 4; pi. 20, fig. 8.Cladophlehis denticulata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 71,pi. 4, fig. 2; pi. 7, fig. 7 (not Nathorst).Cladophlehis, sp., Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 77, pi. 10,figs. 5, 8; pi. 20, fig. 7.Cladophlehis pachyphylla Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 80, pi. 25, fig. 9.Cladophlehis, sp., Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 77, pi. 15,fig. 6; pi. 19, fig. 3.Aspidium angustipinnatum Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 98, pi. 16, figs. 1, 3, 8; pi. 17, fig. 1; pi. 19, fig. 10.Dryopteris angustipinnata Knowlton, Bull. 152, U. S. Geol. Surv., 1898.
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Fon-taine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 540, 544, 548,pi. 114, fig. 6.Aspidium oerstedi f Fontaine, Monogr. 15, U. S. Geol. Surv., 1890, p. 99, pi. 19,fig. 4 (not Heer).Dryopteris oerstedi ? Knowlton, Bull. 152, U. S. Geol. Surv., 1898, p. 92.Description.?A large amount of material has been referred to thisspecies since Dunker's day, so that his diagnosis may be considerablyamplified. In general these forms show the following characters:Fronds large, bipinnate or tripinnate. Rachis stout. Pinnae linearlanceolate, alternate to subopposite, becoming pinnatifid distally.Pinnules usually attached by their whole base, which is slightlyexpanded, contiguous but usually separated to the base, lanceolate,slightly falcate, acuminate. Margin usually entire, more rarelysomewhat dentate in the apical portion. Venation of the usualCladopMehis type. Fertile fronds have the racliis more slenderthan in the sterile fronds. The sori are borne on a distal branch of afurcate vein, as in other Potomac species of Cladophlehis, and form arow on either side of the midvein of the pinnules, which are otherwiseindistinguishable from the sterile pinnules, though inclined to bestraighter.This species has been made to include a large amount of materialfrom various horizons and localities which in the first instance wasdescribed as various species of Neuropteris, Aleihopteris, Pecopteris,Pteris, etc. It is not at all certain that the result may not be a com-posite species made up of several distinct species with indistinguish-able vegetative characters, and it would not be difficult to select stillother forms from various parts of the world which could scarcely beseparated from the foregoing.Cladophlehis alhertsii was not recognized as such in ProfessorFontaine's Potomac studies, but it is obvious that the forms describedas CladopMehis inclinata and Cladophlehis denticulata (this wasdescribed as a new species and is decidedly different from Bron-gniart's species of the same name which Nathorst has referred toCladophlehis) and as Aspidium angustipinnatum are identical with
312 PROCEEDINGS OF TEE NATIONAL MUSEUM. vol.41.each other and with those ferns in the European Wealden which arereferred to dadopJileUs alhertsii. The adcUtional fragments ofPotomac ferns which are referred to this species are not common andare equally unimportant botanically and stratigraphically. The twoCladopMeiis, sp., Fontaine are clearly enough referable to tliis species.CladopMeUs pacJiypTiylla is considered as an anomalous pinna, withthicker, more remote pinnules, which are contracted at the base. Itwas founded on a single fragment from Fredericksburg, Virginia, andif not an example of this species is simply a distal aberrant pinna ofone of the other described species from that locahty. The specimenwhich was the basis for the presence of Aspidium oerstedi Heer in thisflora is the merest fragment without significance in any way.The fertile pinnae of Cladophlehis alhertsii agree with those ofCladopJdehis parva and other Potomac species in the general character,form and arrangement of the sori, the nature of the material precludingany more detailed information on this point. The sori appear to beconfined to the basal part of the proximal pinnules. The presentspecies is closely related to the contemporaneous form Cladophlehisvirginiensis Fontaine.It is common in the Wealden of England and Germany and prob-ably in homotaxial beds in Austria and Russia. It has been recordedfrom the Cenomanian of Bohemia and from the Atane beds of Green-land, but both of these determinations may be considered as verydoubtful. In this country it is definitely known only from thePotomac group. It has been recorded from the Patapsco formationat Vinegar Hill, Maryland, but the single specimen is referred bythe writer to CladopJdehis virginiensis which is abundant at thislocality.Occurrence.?Patuxent formation : Potomac Run, Telegraph Sta-tion (Lorton), Dutch Gap, Trents Reach, Fredericksburg, Virginia.Arundel formation: Arlington, Hanover, Bay View, Maryland.Collections.?United States National Museum, Goucher College.CLADOPm^EBIS BROWNIANA (Dunker) Seward.Pecopteris browniana Dunker, Monogr. Norddeutsch. Wealdenbildung, 1846,p. 5, pi. 8, fig. 7.
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Fontaine, Monogr. U. S. Geol. Survey, vol. 15, 1890, p.88, pi. 22, figs. 10, 11; pi. 23, figs. 2-7; pi. 26, figs. 3, 13; Proc. U. S. Nat.Mus., vol. 15, 1892, p. 492.
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Dawson, Trans. Roy. Soc. Can., vol. 10, sec.4, 1893, p. 84, fig. 3.?YoKOYAMA, Journ. Coll. Sci. Japan, vol. 7, 1895,p. 218, pi. 24, figs. 2, 3; pi. 27, figs. 1-5.Alethopteris reichiana Ettingshausen, Abh. k. k. geol. Reichs., vol. 1, Abth. 3,1852, p. 17.Alethopteris browniana Schimper, Pal. Veget., vol. 3, 1874, p. 502.Cladophlebis browniana Seward, Wealden Flora, pt. 1, 1894, p. 99, pi. 7, fig. 4.
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Ann. S. Afr. Mus., vol. 4, 1903, p. 10, pi. 2, figs. 1-4, 6.
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Knowlton, Smiths.Misc. Coll., vol. 4, pt. 1, 1907, p. 108, pi. 11, fig. 1.?Knowlton, in Diller,Bull. Geol. Soc. Amer., vol. 19, 1908, p. 386.
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Fontaine, in Ward, Monogr.U. S. Geol. Surv., vol. 48, 1906, pp. 272, 510, 517, 538, 544, 547, 557, 572.
NO. 1862. FOSSIL FERNS FROM THE POTOMAC QROVP?BERRY. 313Pecopteris cf. Browniana Nathorst, Denkschr. k. Akad. Wiss. Wien, vol. 57, 1890,p. 53, pi. 5, fig. 5.Cladopklebis inaequiloba Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p.80, pi. 25, fig. 8.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48,1906, p. 510.Cladopklebis petiolata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 80,pi. 22, fig. 8.Cladophlebis oblongifolia Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 74 (part), pi. 7, fig. 5 (not figs. 3, 4 which are referred to Cladophlebisvirginiensis Fontaine).Cladophlebis crenata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 75,pi. 9, figs. 7-9; pi. 10, figs. 1, 2; pi. 13, figs. 1-3; pi. 19, fig. 7; pi. 20, fig. 6.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, p. 547.Cladophlebis alata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 77, pi.19, fig. 5.
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Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp.229, 480, 510, 544, 557, pi. 65, figs. 17-21.Cladophlebis inclinata Fontaine, in Diller and Stanton, Bull. Geol. Soc. Amer.,vol. 5, 1894, p. 450.Cladophlebis, sp., Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 78, pi.19, fig. 2.Pecopteris strictinervis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 84,pi. 13, figs. 6-8; pi. 19, fig. 9; pi. 20, fig. 3; pi. 22, fig. 13; pi. 170, figs. 5, 6.Pecopteris ovatodentata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p.85, pi. 15, fig. 8; pi. 22, fig. 12; pi. 23, fig. 1.Pecopteris microdonta Fontaine, Monogr. U. S. Geol. Snrv., vol. 15, 1890, p. 85pi. 19, fig. 8; pi. 20, figs. 5, 11.Pecopteris rirginiensis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p82, pi. 8, figs. 1-7; pi. 9, figs. 1-6; pi. 24, fig. 2; pi. 169, fig. 3.?Fontainein Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 480, 538, 552, pi. 116figs. 3, 4.Pecopteris constricta Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 86pi. 20, figs. 1, 2, 4.
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Fontaine, iu Ward, Monogr. U. S. Geol. Surv., vol. 481906, p. 519.Pecopteris socialis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 87pi. 21, fig. 7 (not Heer, 1882).Pecopteris angustipennis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p87, pi. 21, fig. 10.Pecopteris cf. virginiensis Yokoyama, Journ. Coll. Sci. Japan, vol. 7, 1895, p. 220,pi. 24, fig. 1.Description.?The American material which the writer refers tothis species is much more abundant than that from abroad, andthe following diagnosis may be attempted:Frond bipinnate or tripinnate. Pinnae elongate, linear in outline.^Pinnules approximate, variable in outline, usually obtuse and becom-ing united distad to form a pinnatifid pinna, which is then constrictedand slightly decurrent at the base. Venation of the CladopTilehistype not well seen in the smaller pinnules because of their coriaceoustexture.Tliis is another cosmopolitan species of Cladoplilebis which maybe composite in nature and which, as commonly preserved in frag-
1 The single form which Fontaine identified with this species has pinnae which shorten rapidly, givingthe frond a deltoid form, and may be properly referable to the allied species Cladoplilebis nngeri.
S14 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.41.mentary specimens, is distinguishable with difficulty from its conge-ners. It is especially close to Cladojphlehis albertsii and Clado])hlebisungeri. It is recorded from the uppermost Jurassic and lowermostCretaceous in Portugal, from the Neocomian of Japan, and fromthe Wealden of England, Germany, and Austria. In America ithas been reported from the Shasta through the Horsetown and inthe base of the Chico formation on the Pacific coast, and from theKootenai formation of Montana and British Columbia.It is well scattered and abundant in the Potomac group, occurringin all three of the formations, but represented for the most part byincomplete specimens showing slight variations, which were madethe basis for many species of Professor Fontaine. Material fromthe Patapsco formation of Maryland shows indistinct oval sori ina single row on either side of the midvein. These are of thetype found associated with a number of other American species ofCladojiMebis.Professor Zeiller ^ has recently reported fertile fronds of Pecopterishrowniana, or of a very similar species, from the Wealden of Peru.These are not figured, but are described as having biseriate, oval,annulate sporangia as in the modern family Schizaeacese and very likethose of the Jurassic genus Klukia of Kaciborski, thus apparentlysomewhat different from those of the American representatives ofthe present species. Fragments from the Neocomian of Japan,showing oval sori, are referred to this species by Yokoyama.^Occurrence.?Patuxent formation: Fredericksburg, Dutch Gap,Alum Rock, Telegraph Station (Lorton), Potomac Run, Virginia;New Reservoir, Ivy City, District of Columbia; Broad Creek (?), Mary-land. Aeundel formation : Arlington, Hanover, Howard BrownEstate, Maryland. Patapsco formation : Brooke and vicinity, Chin-kapin Hollow, Virginia; Federal Hill (Baltimore), Vinegar Hill,Maryland.Collections.?United States National Museum, Johns HopkinsUniversity, Goucher College.CLADOPHLEBIS CONSTRICTA Fontaine, emended.Cladophlebis constricta Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 68,pi. 2, fig. 11; pi. 3, fig. 2; pi. 6, figs. 5,6, 8-14; pi. 21, figs. 9, 13; pi. 169, fig. 2.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 280, 297,504, 528, 547, pi. 77, fig. 26.?Penhallow, Summ. Geol. Surv. Can., 1904(1905), p. 9.?Knowlton, Smiths. Misc. Coll., vol. 4, pt. 1, 1907, p. 109.Cladophlebis latifolia Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 69,pi. 3, fig. 1; pi. 6, fig. 4.Cladophlebis virginiensis Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48,1906, p. 512, pi. Ill, fig. 7.
1 Zeiller, Comptes Rendus, vol. 150, 1910, p. 148S.2 Yokoyama, Journ. Coll. Sci. Japan, vol. 7, 1895, p. 220.
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 315Description.?Frond large, bipinnate or tripinnate. Principalrachis rather slender. Pinnae remote, shortening rapidly distad.Proximad they are pinnatifid, changing first into pinnules withundulate margins and then into those with entire margins in passingtoward the apex of the frond. Pinnules elliptical in outline, con-stricted at the base, which is rounded or subauriculate. Venation ofthe usual Cladoplilebis type.This species has been identified at a number of localities in Mary-land and Virginia, but it is not common at any of these. Outsidethis area it has been reported from the Kootenai of Montana, andvery similar forms occur in the Kome beds of Greenland, as, forexample, those which Heer described as Pecopteris arctica,^ Pecop-teris andersoniana,^ and Pecopteris liyperborea.^ Abroad the speciesdescribed by Schenk * from the German Wealden as Alethopteriscycadina is very close to the American species, as Fontaine hasalready pointed out.Cladoplilebis constricta exhibits considerable variation in the degreeof remoteness and outline of the pinnules, and may possibly includemore than one species, the fact that certain of these aberrant formscome from the low horizon at Fredericksburg while all of the otheroccurrences are from Patapsco outcrops lends some credence to thissuggestion. The species has been reported by Penhallow from theKootenai in Canada, but this determination can not be accepted withcertainty.Occurrence.?Patuxent formation : Fredericksburg, Virginia. Pa-tapsco formation: Hell Hole (?), Brooke, Deep Bottom, Virginia;Federal Hill (Baltimore), Vinegar Hill, Fort Foote (?), Maryland.Collections.?United States National Museum.CLADOPHLEBIS DISTANS Fontaine, emended.Cladophlebis distans Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 77,pi. 13, figs. 4, 5.
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Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48,1906, pp. 280, 572.Dryopteris frederichshurgensis Knowlton, Bull. 152, U. S. Geol. Surv., 1898,p. 92.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 280,512, 538, 548, pi. 112, fig. 2.Aspidium frederichsburgense Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 94, pi. 11, figs. 1-6; pi. 12, figs. 1-6; pL 16, fig. 9; pi. 19, figs. 6, 7.?Pen-hallow, Trans. Roy. Soc. Can., sec. 3, vol. 1; sec. iv, 1908, p. 307.Description.?Frond large and coarse, - bipinnate or tripinnate.Rachis very stout and rigid. Pinnse of the ultimate order mostlyalternate, rarely opposite or subopposite, with rigid and proportion-ally rather slender rachises, very long, linear. Pinnules alternate,
1 Heer, Flora foss. Arct., vol. 1, 1868, p. 80, pi. 1, fig. 13; pi. 43, fig. 5.2 Idem., vol. 3, Abth. 2, 1874, p. 41, pi. 3, flg. 76.
' Idem., vol. 1, 1868, p. 81, pi. 44, fig. 4.< Palaeont., vol. 19, 1871, p. 218, pi. 31, flg. 2.
316 ? PR0CEEDWG8 OF TSE! PAi'lONAL MtJSSVM. toL. 41,oblong or ovate, obtuse, slightly falcate, and usually with a some-what rounded and slightly constricted base, separate, more or lessremote, in some specimens those of the lower pinnae with crenatemargins, those of the upper ones entire, passing in the middle partof the frond through pinnules with undulate margins. Leaf-substancethick and leathery. Midvein of the usual Cladophlehis type, that is,strong at base and dissolving into branches at the summit; lateralnerves of the crenate and undulate pinnules in groups in each tooth,composed of a midvein which sends off alternate simple branches, orelse of forked veins with one of the branches forking again; those ofthe pinnules with entire margins usually once forked, all quite dis-tinct; fertile specimens rare, Sori very large, elliptical or reniform inshape, and distributed in two rows, one on each side of the midvein,attached to the summit of the upper branch of a furcate nerve.This species is quite generally distributed throughout the Potomacformations, although there is but one recorded occurrence from theArundel formation. It is abundant in the Patuxent formation atFredericksburg and outside the Maryland-Virginia area it has beenrecorded from the Kootenai formation of Montana and BritishColumbia and the Shasta of the Pacific coast province.The sterile and fertile pinnae are closely similar in outline andvenation, the former being much more abundantly represented thanthe latter. They are both very similar to those of Clado'pTilebis parvaFontaine and may be compared with a number of European andKome species of Clado'phlebis , Alethopteris , Pecopteris, etc.Occurrence.?Patuxent formation: Fredericksburg, Dutch Gap,Telegraph Station (Lorton), Virginia; Broad Creek, Maryland.Arundel formation: Arlington, Maryland. Patapsco formation:Chinkapin Hollow, Virginia.Collections.?United States National Museum.CLADOPHLEBIS PARVA Fontaine, emended.CladophleUs parva Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 73,pi. 4, fig. 7; pi. 6, figs. 1-3.?Fontaine, in Ward, 19th Ann. Rep. U. S. Geol.Surv., pt. 2, 1899, p. 657, pi. 160, fig. 18; Monogr. U. S. Geol. Surv., vol. 48,1906, p. 225, 280, 510, 538, pi. 65, figs. 5-8.?Knowlton, in Diller, Bull,Geol. Soc. Amer., vol. 19, 1908, p. 386.CladophleUs inclinata Fontaine, in Diller and Stanton, Bull. Geol. Soc. Amer.,vol. 5, 1894, p. 450.?Fontaine, in Stanton, Bull. 133, U. S. Geol. Surv.,1896, p. 15.Cladophlebis, sp., Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 81, pi.26, fig. 15.Aspidiuvi heterophyllum Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p.96, pi. 14, figs. 1-5; pi. 15, figs. 1-5.?Fontaine, in Diller and Stanton, Bull.Geol. Soc. Amer., vol. 5, 1894, p. 450.?Fontaine, in Stanton, Bull. 133,U. S. Geol. Surv., 1896, p. 15.Dryopteris heterophylla Knowlton, Bull. 152, U. S. Geol. Surv., 1898, p. 92.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 483, 650,pi. 115, figs. 7, 8.
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 317Description.?Fronds large, bipinnate or tripinnate. Rachis very-stout. Piiinse linear-lanceolate, becoming somewhat falcate in out-line distad, and passing from alternate to subopposite. Pinnulesrelatively wide, falcate, acuminate in the sterile forms but obtuse inthe fertile, variable in size according to their position. The distal pin-nules which represent the reduced pinnee lower down on the frondare larger and relatively more slender than the pinnules of the lateralpinnae, which are almost as wide as they are long, and falcate. Be-tween the two orders there is every gradation on each frond throughpinnatifid pumse to simple pinnule-hke forms. Margins entire orsUghtly crenate, especially in the fertile pinnules, which are widerthan the sterile. Lateral veins usually but once forked, sometimessimple. Texture coriaceous. Sori large, reniform in outHne, in threeor four pairs on either side of the midvein at the end of a distal branchof a furcate vein. The structure or arrangement of the sporangiacan not be made out but the spores are preserved in abundance.They are small, ranging from 0.083 mm to 0.05 mm in diameter, withvery thick walls, the outer surface covered with fine granulations notvisible with magnifications of 200 diameters or less. The tetrad scarsare very distinct. In form as well as size these spores are variable.The smaller, possibly immature, spores are trigonal in outline, w^hilethe larger are more nearly spherical.This is a large and handsome species and is represented in the col-lections by material of both the sterile and fertile fronds. It rangesfrom the bottom to the top of the Potomac deposits, and outside theMaryland-Virginia area is recorded from the Shasta beds of the Pacificcoast, the Kootenai of Montana, and the Lakota formation of theBlack Hills. There are a number of European Wealden species whichare similar to CladoiJhlebis jparva, but it is beheved to be quite dis-tinct from its contemporaries, although small fragments of almost anyof the species of CladoplileMs are likely to be confused.Occurrence.?Patuxent formation : Fredericksburg, Cockpit Point,Potomac Run, Virginia. Arundel formation: Ai'hngton (?), Mary-land. Patapsco formation: Vinegar Hill, Maryland.Collections.?United States National Museum, Goucher College.CLADOPHLEBIS ROTUNDATA Fontaine, emended.Cladophlebis rotundata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 78,pi. 20, figs. 9, 10.?(?) Penhallow, Summ. Geol. Surv. Can. 1904(1905), p.9.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 491, 510.Cladophlebis brevipennis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 81, pi. 36, fig. 1.Description?In 1890 Fontaine describes this species as foUows:Frond bipinnate or tripinnate, arborescent(?); principal rachis stout, rounded, andprominent; pinnae short, with a strong rigid rachis; ultimate pinnae, from the lower.
318 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 41.part of the frond, with alternate, short, broadly ovate, very obtuse, round-lobedpinnules, those of the upper part of the frond having the lowest pinnules distinctand more or less round-lobed, and toward the summit with pinnules passing throughsuch forms as rotundate, subrhombic, and decurrent to entii^e and rounded, the latterhaving the tips round-lobed and very obtuse ; nerves varying according to the positionand shape of the pinnules, those of the round-lobed pinnules and of the pinnte reducedto pinnules flabellately diverging in each lobe, the branches being either forked orsimple. The nerves of the subrhombic pinnules have a midnerve, which sends offalternately on each side forked or simple branches. All the nerves are very stronglymarked and stout. The leaf-substance is thick and leathery.The foregoing description was written for Cladophlebis rotundata,but it requires no alteration to include the rare fragments which werenamed Cladophlelis hrevipennis. as the material on which the twowere founded is identical; in fact, the description of the latter waspractically a paraphrase of the former.This species, while founded upon rather scant remains, is wellcharacterized by the strong venation and the breadth of the shortovate pinnules. It may possibly represent Cladoplilehis constridaFontaine, as it closely resembles the form of the latter species whichProfessor Fontaine named CladopTdelis latifolia. It has been recordedby PenhaUow from Yukon Territory in Canada, but the identificationis very doubtful.Occurrence.?Patuxent formation: Fredericksburg, Dutch Gap,Virginia. Patapsco formation: Mount Vernon, Cliinkapin Hollow,Virginia.Collections.?Vnited States National Museum.CLADOPHLEBIS UNGERI (Dunker) Ward.Pecopteris ungeri Dunker, Monogr. Norddeutsch. Wealdenbildung, 1846, p. 6,pi. 9, fig. 10.Pecopteris polymorpha Dunker, Monogr. Norddeutsch. Wealdenbildung, 1846,p. 6, pi. 7, fig. 5 (not Brongniart).Pecopteris dunkeri Schimper, Pal. Veget., vol. 1, 1869, p. 539.Pecopteris exiliformis Geyler, Palaeont., vol. 24, 1877, p. 226, pi. 30, fig. 1.Aspidium dunkeri Fontaine, Monogr. U. S. Geol Sm'v., vol. 15, 1890, p. 101,pi. 22, figs. 9, 9a, 96; pi. 25, figs. 11, 12; pi. 26, figs. 2, 8, 9, 18; pi. 54, figs. 3, 9.?Fontaine, in Diller and Stanton, Bull. Geol. Soc. Amer., vol. 5, 1894, p.450.?Fontaine, in Stanton, Bull. 133, U. S. Geol. Surv., 1896, p. 15.Cladophlebis dunkeri Seward, Wealden Flora, pt. 1, 1894, p. 100, pi. 7, fig. 3.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 510, 538.Pecopteris exilis Yokoyama, Journ. Coll. Sci. Japan, vol. 3, 1890, p. 35, pi. 1,figs. 8-10.Aspidium parvifolium Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p.100, pi. 21, fig. 6; pi. 24, fig. 8; pi. 25, fig. 10; pi. 26, figs. 1, 14, 16, 17.Dryopteris parvifolia Knowlton, Bull. 92, U. S. Geol. Surv., 1898, p. 92.
?
Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, p. 486 (not p.541, pi. 114, fig. 7).Pecopteris geyleriana Nathorst, Denkschr. k. Akad. Wiss. Wien, vol. 57, 1890, p.48, pi. 4, figs. 2-6.?Yokoyama, Journ. Coll. Sci. Japan, vol. 7, 1895, p. 219,pi. 21, fig. 12; pi. 23, figs. 1, la; pi. 38, fig. 5.
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 319Pecopteris, sp., Nathorst, Denksckr. k. Akad. Wiss. Wien, vol. 57, 1890, p. 48,pi. 4, figs. 2-6.Cladophlebis ungeri Ward in Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol.48, 1906, pp. 228, 510, 538, pi. 65, figs, 15, 16.?Knowlton, in Diller, Bull.Geol. Soc. Amer., vol. 19, 1908, p. 386.Pecopteris brevipennis Fontaine, Monogr. U. S. Geol. Sm-v., vol. 15, 1890, p. 86,pi. 21, figs. 1-3.
?
Fontaine, in Ward, Monogi*. U. S. Geol. Surv., vol. 48,1906, p. 510.Pecopteris pachyphylla Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 88,pi. 26, figs. 4, 5.Description.?A satisfactory diagnosis is the one written by Pro-fessor Fontaine for his Aspidium Dunkeri which will answer not onlyfor that material but for all of the other supposed species founded byFontame upon various fragments of CladopJilehis ungeri. It is asfollows
:
Frond bipinnate or tripinnate, arborescent; principal rachis stout and rigid; ulti-mate pinnse alternate, short, linear-lanceolate; pinnules alternate or subopposite,short, closely placed, narrowed at the base, cut more or less deeply into lobes or teethwhich are ovate or oblong, obtuse or subacute, very small, those of the fertile portionsof the frond standing nearly perpendicular to the rachis and having in each lobe orpinnule a simple lateral nerve which bears a sonis on its summit, those of the sterileand more common portions more obliquely placed, mostly subacute, with nervesin each lobe that fork simply in the upper ones, and in the lower ones are composed ofa midnerve with alteiTiate simple branches; leaf-substance thick; sori very minute,club-shaped or elliptical, visible distinctly only with the help of a lens, and presentonly in the pinnules of the lower part of the pinnse, and mostly found on the lobestoward the base of these.This species was described by Dunker in. 1846 from the Wealden ofNorthern Germany as Pecopteris ungeri and Pecopteris poli/morpha.Schimper in 1869 renamed the latter Pecopteris dwiikeri for the reasonthat the specific name polymorpha had been used by Brongniart in1828. Schenk two years later, with Dunker's original specimensbefore him, announced that Dunker's ungeri and polymorpha weresynonymous. He did not, however, restore Dunker's name norhas Seward done so iii his discussion (1894) of tliis species in the"Wealden Flora." In accordance wdth the prevaiHng system ofnomenclature Dunker's original name must be used for this species,and this proposal was made by Ward in 1906. Seward in 1894 referredthe species to the genus Cladophlebis and while the American materialavailable in the present treatment of this species is not as completeas might be desired it furnishes some evidence regarding the fertilefronds of still another species of Cladophlehis. The character of thefertile material is rather vague and while it is clearly congeneric witha number of other of Fontaine's species of Aspidium, it is hardlysufficient evidence of their relationsliip with that modern genus.The present species is close to Cladophlehis hrowniana and is appar-ently a cosmopolitan Lower Cretaceous type since indistinguishablematerial occurs not only in the English and Continental Wealden
320 PROCEEDINaS OF THE NATIONAL MUSEUM. vol. 41.deposits (Belgium, Germany, Austria), but in the Neocomian ofPortugal and Japan, and in the Uitenliage series of South Africa.Material obtained from Japan shows obscure fruiting fragments inwhich the pinnae are narrowed, and there is apparently a single sorusto each pinnule.^ The species is also reported from the Albian ofPortugal by Saporta. In America it is not rare in the Potomac bedsand rather doubtful remains are referred to this species from theShasta beds of California. It is probably represented in the Kootenaiformation of Montana by Dryopteris m,ontanense (Fontaine) Ivnowl-ton.2 Professor Seward in a recent paper ^ expresses his belief thatthis species is identical with Cladoplilehis hrowniana, such differencesas are observable bemg merely individual and not specific. Thismay be the case as the two are certainly closely allied. There is,however, serious danger in unitmg under a smgle specific name fernfronds from all quarters of the globe which resemble each other,unless the evidence of their identity is very strong.Occurrence.?Patuxent formation: Woodbridge, Fredericksburg,Dutch Gap, Telegraph Station (Lorton), Virginia. Patapsco forma-tion: Chinkapin Hollow, Virginia.Collections.?^United States National ]\fuseum.CLADOPHLEBIS VIRGINIENSIS Fontaine, emended.CladopMebis virginiensis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 70,pi. 3, figs. 3-8; pi. 4, figs. 1, 3-6 (not Fontaine, 1906).CladopMebis falcata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 72,pi. 4, fig. 8; pi. 5, figs. 1-6; pi. 6, fig. 7; pi. 7, figs. 1, 2.?Fontaine, in Ward,Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 227, 280, 511, 548, pi. 65, figs.12-14; pi. Ill, fig. 6.?Knowlton, in Diller, Bull. Geol. Soc. Amer., vol. 19,1908, p. 386.CladopMebis acuta Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 74, pi. 5,fig. 7; pi. 7, fig. 6; pi. 10, figs. 6, 7; pi. 11, figs. 7, 8; pi. 166, fig. 5.?Fon-taine, in Ward, Monogr. U. S. Geol. Sm-v., vol. 48, 1906, p. 538, pi. 114,figs. 3, 4.TMmnfeldia variabilis Fontaine, in Diller and Stanton, Bull. Geol. Soc. Amer.,vol. 5, 1894, p. 450.?Fontaine, in Stanton, Bull. 133, U. S. Geol. Surv.,1896, p. 15.CladopMebis acuta angustifolia Fontaine, in Ward, Monogr. U. S. Geol. Surv.,vol. 48, 1906, p. 539, pi. 114, fig. 5.Asplenium distans Dawson, Trans. Roy. Soc. Can., vol. 3, sec. 4, 1886, p. 5, pi. 3,fig. 7 (not Heer).TMnnfeldia vwntanensis Fontaine, in Weed and Pirsson, 18th Arm. Kept. U. S.Geol. Surv., 1896-97 (1898), pt. 3, p. 481.CladopMebis falcata montancnsis Fontaine, in Ward, Monogr. IT. S. Geol. Surv.,vol. 48, 1906, p. 291, pi. 71, figs. 14-20.CladopMebis oblongifolia Fontaine, Monogr. U. S. Geol. Siu^., vol. 15, 1890,p. 74 (part), pi. 7, figs. 3, 4 (not fig. 5, wfiich is referred to C. hrowniana).
? Nathorst, Denkschr. k. Akad. Wiss. Wien, vol. 57, 1890, pi. 4, figs. 3-5; of these fig. 3 is referred toWeichselia viantelli by Seward, 1894.2 Fontaine, Proc. U. S. Nat. Mus., vol. 15, 1892, p. 490, pi. 82, figs. 1-3; pi. 83, figs. 2-3o.8 Sewaxd, Ann. S. Afr. Mus., vol. 4, 1903, p. 10.
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 321Description.?Frond large, bi- or tripinnate. Rachis stout andrigid. Ultimate pinnae long, rather remote, alternate to subopposite.Pinnules ovate to lanceolate and subfalcate in outline, sometimesobtusely pointed mostly separate to the base, attached by their wholebase which is more or less widened. Venation of the type usual in thisgenus. Margms usually entire, sometimes crenulate to subdentatebecoming entire distad. Texture coriaceous. The degree of sepa-rateness of the puinules as well as their relative length and breadthand their more or less falcate form are characters dependent upon theage of the frond or the position of the pinnules on the frond, longnarrow almost straight proximal pinnules passing gradually intomore or less short, broad and falcate distal pinnules.This species is not very different from the widespread type ofCladopMehis commonly referred to the species alhertsii of Brongniart.It exhibits considerable variation from specimen to specimen, butthese variations show so many gradations and are so readily explainedwhen the position of the various fossil fragments upon the frond istaken into consideration that any segregation of them is entirelyunwarranted. In general the pinnules are larger and relativelymuch wider than in CladopMehis alhertsii.The present species is very common at certain localities both in thePatuxent and Arundel formations, and although it apparently sur-vives during the deposition of the Patapsco formation it is less com-mon. Outside of the Maryland-Virginia area remains of this specieshave been reported from the Shasta beds of California and from theKootenai of Montana and British Columbia. Seward ^ refers thebulk of Fontaine's figures of CladopMehis virginiensis Fontaine toTodites williamsoni (Brongniart), a widespread older Jurassic species,but this reference has no justification. CladopMehis nathorsti Yoko-yama - from the Neocomian of Japan is very close to the presentPotomac species.Occurrence.?Patuxent formation: Fredericksburg, Dutch Gap,Potomac Run, Virginia. Arundel formation: Arlington, Maryland.Patapsco formation: Vinegar Hill, Maryland; Chinkapin Hollow,Virginia.Collections.?United States National Museum, Goucher College.THE GENUS ONYCHIOPSIS.Yokoyama characterized the genus Onychiopsis as follows : " Fertilesegments different from the sterile. Sori terminal, linear, on eachside of the midrib, parallel with the margin, involucrate ; the involu-crum of each side confluent over the midrib." ^ It was based on a
1 Seward, Fossil Plants, vol. 2, 1910, p. 340.2 Yokoyama, Journ. Coll. Sci. Japan, vol. 7, 1895, p. 220, pi. 28, figs. 3, 4, 10, 11.3 Idem., vol. 3, 1890, p. 26.94428??Proc.N.M.vol.41?11 21
322 PROCEEDINGS OF THE NATIONAL MUSEUM. tol. 41.Japanese Upper Jurassic or Neocomian species originally describedby Geyler as Thyrsopteris elongata and founded upon sterUe pinnules.The discovery of fertile pinnules by Yokoyama led to the erection ofthe present genus which is very close to the modern genus OnycMumKaulfuss, which is made a subgenus of Cryptogramme R. Brown byDiels in Engler and Prantl's Natiirhchen Pflanzenfamilien (1899),although there seems to be but shght warrant for Diel's treatment.Seward in working over the abundant Wealden material in theBritish Museum found that the widespread species which usuallywent by the name of Splienopteris mantelli Brongniart was congenericwith Yokoyama's species mentioned above, and he therefore rede-scribed Brongniart's species as Onychiopsis mantelli, redefining thegenus in the following terms :^Frond tripinnate, main rachis slender, may be winged, pinnae alternate, approxi-mate, lanceolate. Pinnules narrow, lanceolate, acute, alternate, the larger onesserrate, and gradually passing into pinnules with narrow ultimate segments. Fertilepinnae with alternate elliptical pinnules which differ in shape from the sterile pinnulesand have the sporangia on the lower surface, giving them the appearance of raisedelliptical bodies.The most abundant and characteristic ferns of the Potomac groupwere referred by Professor Fontaine to Thyrsopteris Kuntze, anexisting monotypic genus of the family Cyatheacese inhabiting theisland of Juan Fernandez, Of these some 40 species, so called, weredescribed. They were all based on sterile fronds or parts of fronds,often extremely small and inadequate fragments. Professor Fontaine,after quoting Heer's diagnosis of Thyrsopteris ^ writes:This description, given by Heer for the genus Thyrsopteris, so far as the portionpertaining to the sterile frond is concerned, agrees well with a large number of speciesin the Potomac flora. These I place provisionally in the genus Thyrsopteris, onaccount of the great resemblance that the shape of the pinnules, the lobing, and thenervation show to the sterile forms of various species determined to be Thyrsopterisby their fructification. As, however, no fructification is found in the Potomac species,the placing of these plants in the genus must be regarded as provisional. It is quitepossible that some of them belong to Aspidium and Dicksonia.It should be noted that a number of the species of Thyrsopteris described in thefollowing pages show a good many features similar to those of Sphenopteris mantelli, asdescribed by Schenk and Heer (p. 120).Professor Fontaine does identify Sphenopteris mantelli from onelocality in the Potomac belt, that at Federal Hill, Baltimore, and indiscussing its bearing upon the age of the deposits he says:Now in the Potomac flora not only is S. mantelli present in beds which show plantsof the most recent facies existing in the formation, but there is a very important groupof ferns which, although placed in the genus Thyrsopteris, have nearly the nervationand foliage typified in S. mantelli. The great development in the Potomac of fernsof the general type of S. mantelli gives strong evidence of Wealden or somewhat laterage. A somewhat later age than Wealden is indicated, perhaps, as most of the species
? Flora foss. Arct., vol. 4, pt. 2, 1877, p. 28. ! Seward, Wealden Flora, pt. 1, 1894. p. 40.
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 323
are somewhat modified, eo as to depart more or less from the typical S. mantelli, andto assume the facies of Thyrsopteris. The other species of Sphenopteris give little helpin fixing the age of the Potomac strata (p. 338).Thus while the most prominent fern element in the Potomac groupbelongs to a different genus and different famUy, its resemblance tothe Sphenopteris mantelli type is so pronounced that it furnishes anargument for the nearly homotaxial age of the containing deposits,surely a curious logic. In his latest work this author identifies aspecies of OnycJiiopsis from three localities in Virginia and Marjdand(Hell Hole, New Reservoir, and Fort Foote).Again in discussing Thyrsopteris at the end of his Potomac flora(1890) he writes:It is true that, as no fructification has been found on these ferns, they may be incor-rectly placed in the genus Thyrsopteris. Still, the very great development in thePotomac flora of ferns with a foliage and nervation so characteristic of the later Jurassicand Lower Ci'etaceous can not be without significance.A number of these Thyrsopterids have the same type of foliage as the Wealden ferns,Sphenopteris mantelli Brongn.; S. goepperti Dunker; 5'. cordai Schenk; S. plurinerviaHeer; and S. gomesiana Heer, as well as the Urgonian plants Asplenium dicksonianumHeer; A. nauck hoffianum Heer, and various Dicksonias, such as D. johnstrupi Heer.It is a significant fact that this type of foliage, so common toward the close of theJurassic and in the oldest Cretaceous, is the most abundant single type in the Potomacstrata also. Such a general prevalence of a type is more significant of geological rela-tionship than the identification of a few species common to two formations. It isnot worth while to examine in detail the affinities of the different species. Most ofthem are new and unique. One or two have some resemblance to Oolitic species,while a greater number may be grouped as belonging to the two Wealden types S.mantelli and S. goepperti.It will be seen from these length}' quotations how uncertain theauthor of these 40 species of Thyrsopteris was as to their real botanicalaffinity, and when the student turns from the text and figures to theactual specimens, the strictures of Professor Seward ^ are found to beabundantly justified. There are 26 species described from a singleclay lens at Fredericksburg, Virginia. If the reader wdl pause to askhimself where in the history of the earth or in the living flora 26 speciesof a single genus of ferns can be found in a single circumscribed claylens, or growing in a single cu'cumscribed area, grave doubt as to theirvalidity at once arises; and even if we predicate their having beengathered together by a river S3"stem it must needs have been a re-markable river system to have gathered all of these ferns with over50 other species of ferns and 50 species of gymnosperms, in all 160different species, and to have deposited them in one quiet pool whereclay was forming, a pool not over 15 feet in diameter as preserved andonly 4 feet tliick, the recognizable remains practically all coming fromthe basal 3 to 5 inches.
1 Wealden Flora, pt. 2, 1894, p. 56.
324 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 41.With the large amount of material at his disposal the writer finds italtogether impossible to differentiate the 40 species described byProfessor Fontaine from the Potomac group. There are two maintypes, the narrow pinnule type, that identified m some of the Balti-more specimens as SijlienoioUris mantelli by Fontaine and includmgsome of the forms described as new species of Thijrsopteris, and thebroader type exemplified by the foreign Splienopteris goepperti. It isto the latter that a large number of the Potomac forms belong. Threeadditional species which include the balance of the Thyrsopteris formsare characterized. In perusing the synonym of the species whichfollow, the question is likely to arise m the mmd of the reader whetheror not the process of ignoring minor difterences has not been carriedtoo far, so that it is needfid to pomt out the reasons which have ledto the present treatment. The main reason is, of course, that it wasfound impossible to fix upon any characters of specific value thatwould hold good for material other than the individual specimen uponwhich they were based. That the author of these species could nottell them one from the other is quite obvious m looldng over thematerial which passed through his hands, specimens identical in allparticulars at one time receivmg one name and on a subsequent occa-sion another, even counterparts of the same specimen being, in at leastone instance, identified as distinct species.These ferns were of large size with tripinnate fronds, so that it iseasy to see how one or two species with slight individual variations inform could, when broken up into fragments and fossilized m a matrixfor the most part of very arenaceous clay, form the basis for numerousspecies. The pinnsB from the base of the frond will difl^er more or lessfrom those higher up and the basal pinnules of the individual pmnsewill diflfer decidedly from the distal ones. It is possible in the morecomplete Potomac specimens to trace these variations and so get anumber of Fontaine's types on a single specimen so that it seems wiserto consider the bulk of the forms as exemplifying slight variations,due largely to position, rather than to allow them specific or evenvarietal rank. The published drawings of these forms, especially theenlarged pinnules showing detail, are for the most part inaccurate andidealized to such an extent that even the experts in the NationalMuseum often find it impossible to decide which specimens representProfessor Fontaine's drawings.With regard to our taking up the genus OnycJiiopsis of the Polypo-diaceoe rather than Thyrsopteris of the Cyatheacese it may be said thatwhile Tliyrsopteris as a form-genus may not be open to any greatdegree to criticism, it implies a relationship with the existing specieswhich the evidence does not substantiate so that the best modernusage refers the older type of this sort to the genus Coniopteris Brong-niart and the later ones to this genus OnycJiiopsis. It is quite possible
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 325that the modern genus Thyrsopteris was a promment Jurassic andolder Cretaceous type, there bemg many parallel cases, as, for example,that of the gymnospermous genus Ginkgo. Some of the evidence isat least sufficient to prove that forms so named are referable to thefamily Cyatheacefe, so that in considering the Potomac forms wehave to decide whether the fact that the Jurassic forms like Thyr-sopteris maakiana and Thyrsopteris murrayana of Heer are membersof the Cyatheaceae, shall be given greater or less weight than the factthat the same type of sterile frond very abundant in the Lower Cre-taceous, from England to Japan, should have fertile pinnules like thoseof the genus OnycJiium of the Polypodiace?e. It is true that onlysterile pinnules are knovvTi from the Potomac deposits, but the fertileparts have been found associated and in organic connection withthese identical sterile pinnules in nearly homotaxial beds in California,Japan, England, Belgium (?), Bohemia, and Portugal. The writerprefers to believe that the latter evidence is entitled to the greaterweight. The modern genus Onychium has several widel}" distributed,chiefly tropical, species of Japan, China, India, Persia, Abyssinia, andthe East and West Indies. In this connection attention should becalled to the fertile specimens described by Professor Fontaine, fromFredericksburg, as Aspleniopteris, since the latter, which is referredto the Aspleniese, is ver}^ similar to the fertile pinnae of a specimen ofOnycMopsis goepperti from Japan, kindly communicated by ProfessorYokoyama. ONYCHIOPSIS GOEPPERTI (Schenk) Berry.Sphenopteris goepperti Schenk (part), Palaeont., vol. 19, 1871, p. 209 (7), pi. 30(4) figs. 2, 2a (not figs. 3-5 or pi. 35 (9) fig. 2).?Saporta, Flora Foss. Portugal,1894, pp. 71, 123, 159, pi. 18, fig. 6; pi. 33, fig. 8; pi. 29, fig. 6.Thyrsopteris elongata Geyler, Palaeont., vol. 24, 1877, p. 221.
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Schenk inRichthofen's China, vol. 4, 1883, p. 263, pi. 54, fig. 1.Dicksonia elongata Yokoyama, Bull. Geol. Soc. Japan, vol. 1, No. 1, 1886, p. 5.Onychiosis elongata Yokoyama, Joum. Coll. Sci. Japan, vol. 3, 1890, p. 27, pi. 2,figs. 1-3; pi. 3, fig. 6d; pi. 12, figs. 9, 10.?(?) Seward, Wealden Flora, pt. 1,1894, p. 55, pi. 2, fig. 2.Thyrsopteris rarinervis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 123,pi. 26, figs. 6, 7; pi. 43, figs. 4-6; pi. 44, figs. 1, 2, 5; pi. 49, fig. 2; pi. 169,figs. 6, 7.
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Fontaine, in Ward, Monogr. U. S. Geol. Sm-v., vol. 48, 1906, pp.225, 484, 491, 514, 517, 518, 521, 528, 548, pi. 65, figs. 2-A; pi. 113, figs. 2, 3.Thyrsopteris alata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 124,pi. 36, fig. 3.Thyrsopteris meehiana angustiloba Fontaine, Monogr. U. S. Geol. Surv., vol. 15,1890, p. 126, pi. 38, figs. 5-7, 9; pi. 43, fig. 8; pi. 44, fig. 3; pi. 47, fig. 4; pi. 48,fig. 1; pi. 54, figs. 2, 11; pi. 55, fig. 1; pi. 56, figs. 1-3.
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Fontaine, in Ward,Monogr. U. S. Geol. Surv., vol. 48, 1906, p. 557.Thyrsopteris angustiloba Fontaine, Monogr. U. S. Geol. Sm-v., vol. 15, 1890, p. 134,pi. 48, figs. 3-5; pi. 55, fig. 3.Thyrsopteris densifolia Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 129,pi. 39, fig. 3; pi. 40, figs. 2-5; pi. 51, fig. 5.
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Fontaine, in Ward, Monogr.U. S. Geol. Surv., vol. 48, 1906, pp. 484, 511, 517.
326 PROCEEDINGS OF THE NATIONAL MVSEVM. vol.41.
Thyrsopteris demrrens Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 130,pi, 43, fig. 7; pi. 46, figs. 2, 4; pi. 49, figs. 5-7.?Fontaine, in Ward, Monogr.U. S. Geol. Surv., vol. 48, 1906, pp. 484, 491, 511, 525, pi. Ill, fig. 11.Thyrsopteris virginica Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 120,pi. 24, fig. 1.Thyrsopteris pachyrachis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p.132, pi. 46, figs. 3, 5; pi. 47, figs. 1, 2; pi. 49, fig. 1.?Fontaine, in Ward,Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 487, 538, 557.Thyrsopteris elliptica Fontaine, Monogr. U. S. Geol. Svu-v., vol. 15, 1890, p. 133,pi. 24, fig. 3; pi. 46, fig. 1; pi. 50, figs. 6, 9; pi. 51, figs. 4, 6, 7; pi. 54, fig. 6;pi. 55, fig. 4; pi. 56, figs. 6, 7; pi. 57, fig. 6; pi. 58, fig. 2.?Fontaine, in Ward,19th Ann. Kept. U. S. Geol. Surv., pt. 3, 1898, p. 482; pt. 2, 1898, p. 482.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 290, 484,514,517, 528, 557, pi. 71, figs. 12, 13.?Knowlton, Smiths. Misc. Coll., vol. 4,pt. 1, 1907, p. 110.Thyrsopteris distans Fontaine, Monogr. IT. S. Geol. Surv., vol. 15, 1890, p. 134,pi. 47, fig. 3; pi. 54, fig. 8.Thyrsopteris pinnatifida^o-titA.m'E, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 136,pi. 51, fig. 2; pi. 54, figs. 4, 5, 7; pi. 57, fig. 7.?Fontaine, in Ward, 19thAnn. Kept. U. S. Geol. Surv., pt. 2, 1890, p. 658, pi. 161, figs. 1, 2.?Fontaine,in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, p. 511.Thyrsopteris varians Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 137,pi. 52, figs. 2^; pi. 53, figs. 1-3; pi. 54, fig. 10; pi. 57, fig. 2.Thyrsopteris 7-hombifolia Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 138,pi. 52, fig. 5; pi. 54, fig. 1.Thyrsopteris bclla Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 139, pi. 53,fig. 5; pi. 55, figs. 6, 7; pi. 56, figs. 2, 5; pi. 57, figs. 1, 5; pi. 58, fig. 4.?Fon-taine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 491, 511.Thyrsopteris microloba Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 140,pi. 57, fig. 4.Thyrsopteris microloba alata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 140, pi. 55, fig. 5; pi. 58, fig. 1.
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Fontaine, in Ward, Monogr. U. S. Geol.Surv., vol. 48, 1906, p. 281.Thyrsopteris insequipinnata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 142, pi. 57, figs. 3, 8.Thyrsopteris rhombiJoba Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 144,pi. 89, fig. 7; pi. 60, fig. 8.Description.?Yokoyama, in 1890, described this species as follows:Frond slender, bi-tripinnated ; sterile pinnae alternate or rarely opposite, elongated,their length rapidly increasing toward the lower part of the frond; pinnules alternate,acutely directed forward, lanceolate or linearly lanceolate, entire or lobed, or evenpinnately parted; lobes or partitions acute at apex and acutely directed forwardjust like the pinnules themselves. Venation obsolete, secondary veins simple, eachgoing into a lobe. Fertile pinnules elongated, with a linear terminal sorus on bothsides of the midrib
.
A very large number of Fontaine's species of Thyrsopteris fall withinthe limits of this species. There is, to be sure, some variation in therelative length and breadth of the pinnules, but the material showsevery gradation of form, it being possible to select individual pinnulesfrom a single frond fragment which exemplify several of the su]i-posed types. On the whole the pinnules are somewhat more robust
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 327than ill the foreign material, and the rachis is inclined to be stouter andmay or may not be winged.This is an exceedingly common form in the Potomac from the oldestto the youngest stratum and it has also been recorded from theKootenai of Montana at Great Falls, Geyser, etc., and possibly someof Dawson's identifications of Asplenium dicksonianum Heer from theCanadian Kootenai should also be referred to this species. It alsooccurs in the Lakota formation of the Black Hdls, Abroad it is ratherrare in the English and German Wealden, but its geological distribu-tion in the Lower Cretaceous of Portugal rivals that of eastern Amer-ica since it comprises considerable material from the Valanginian,Urgonian, and Albian terranes. With regard to its occurrence in theMesozoic of eastern Asia, Yokoyama writes^ that it is the ''chiefand characteristic fossil of the Japanese flora, being found in all ofthe fossil localities."That this or OnycJiiopsis psilotoides, or both, occur in the Kome bedsof western Greenland seems probable, and several of Heer's species ofAsplenium, notably Asplenium dicksonianum Heer,^ suggest them-selves for comparison. While the writer has not ventured to includeany of them in the synonymy of this species, they certainly are veryclose to this type in appearance. The English occurrence of thisspecies is questioned in the foregoing synonymy since ProfessorSeward ^ considers the Wealden material as identical with that ofOnycJiiopsis psilotoides. This may be true of the Wealden materialreferred to, but it can hardly apply to that from America and Asia, asthe writer will show under the discussion of OnycJiiopsis psilotoides.Occurrence.?Patuxent fokmation: Fredericksburg, Trents Reach,Cockpit Point, Dutch Gap, near Potomac Run, Colchester Road(Pohick Creek?), Virginia; New Reservoir, Ivy City, District ofColumbia. Arundel formation: Langdon, District of Columbia,Arlington(?), Maryland. Patapsco formation: Federal Hill (Balti-more), Fort Foote, Vinegar Hill, Maryland; near Brooke, WhiteHouse Bluff, Mount Vernon, Chinkapin Hollow, Virginia.Oollections.?United States National Museum, Goucher College.ONYCfflOPSIS NERVOSA (Fontaine).Thyrsopteris nervosa Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 122,pi. 25, figs. 4, 5, 16; pi. 37, figs. 2, 4; pi. 39, fig. 5; pi. 40, fig. 6.?Fontaine,in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, pp. 511, 517, 519, 521, 528,548, 571.Thyrsopteris meekiana Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 125,pi. 38, figs. 2-4, 8; pi. 50, figs. 7, 8; pi. 51, fig. 3.
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Fontaine, in Ward, IMonogr.U. S. Geol. Sm-v., vol. 48, 1906, pp. 519,565; pi. 119, fig. 1.
1 Yokoyama, Journ. Coll. Sci. Japan, vol. 3, 1890, p. 27.2 Flora foss. Arct., vol. 3, Abth. 2, 1874, p. 31, pi. 1, figs. 1-5; idem, vol. 6, Abth. 2, 1882, pp. 3, 33, pi. 2,fig. 2; pi. 32, figs. 1-8.5 Seward, Ann. S. Afr. Mus., vol. 4, 1903, p. 7.
328 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 41.Thyrsopteris crassmervrs Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 130,pi. 41, figs. 1-3.?Fontaine, in Ward, 19th Ann. Rept. U. S. Geol. Surv.,pt. 2, 1899, p. 658, pi. 161, figs. 3, 4.?Fontaine, in Ward, Monogr. U. S.Geol. Surv., vol. 48, 1906, pp. 513, 528, pi. 112, figs. 5, 6.Thyrsopteris pecopteroides Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 135, pi. 51, fig. 1.?Fontaine, 19th Ann. Rept. U. S. Geol. Surv., pt. 2,1899, p. 661, pi. 161, figs. 16-19.Adiantites parvifolius Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48,1906, p. 558, pi. 117, fig. 1.Thyrsopteris heteroloba Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 139,pi. 53, fig. 4.Thyrsopteris obtusiloba Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p.143, pi. 58, figs. 7, 10.Description.?Frond bipinnate or tripinnate. Principal rachismediumly stout, somewhat flexuous, sometimes winged in the upperpart. Pinnae alternate or subopposite, ovate to ovate-lanceolatein outline, becommg entire apicall}^, the pinnules passing into dentateteeth while the ultimate pinnse become dentate pinnules. This char-acter renders distal fragments quite different in appearance from thenormal form of this species and quite like CladoplileMs. In someindividuals the pinnse lower down on the frond assume this form, con-stituting the supposed species Tliyrsopteris crassinervis of ProfessorFontaine and well showm in the specimens from Chinkapin Hol-low and from near Glymont. Every gradation is shown, however,between this type and the usual type of pinnae made up of alter-nate,- very oblique, decurrent pinnules, usuall}^ rather deeply cut intosubrhombic basal lobes, which become ovate or elliptical lobes andfinally teeth in passing distad. Base contracted, subpetiolate. Veinsnumerous and slender but very distinct, branching obliquely, flabellate,repeatedly forked, subparallel. Texture coriaceous.Wliile the fragments of the fronds of this species are all small, theplant which bore them must have been of considerable dimensions.Representative material is readily distinguished from the otherspecies of Onycliiopsis recognized, but small fragments are liable toconfusion with Onycliiopsis hrevifolia; in fact, Professor Fontainefounded no less than six nominal species upon such fragments, all ofwhich are beUeved by the ^\Titer to represent slight variations of asingle species.It is widely distributed throughout the Potomac group, but notcommon at any outcrop. Outside this area it has been reported fromthe Lakota formation of the Black Hills. Practically identical re-mains from the Lower Cretaceous of Portugal are described by Saportaas various species of Sphenopteris.Occurrence.?Patuxent formation: Fredericksburg, Dutch Gap,Potomac Run, Virginia; New Reservoir, Ivy City, District of Colum-bia; Sprhigfield, Maryland. Arundel formation: Langdon (fre-quent), District of Columbia. Patapsco formation : Chinkapin Hoi-
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 329low, Virginia; Fort Foote, near Glymont, Vinegar HUl (?), FederalHill (Baltimore), Maryland.Collection.?United States National Museum, Maryland Academyof Science, Goucher College.ONYCHIOPSIS BREVIFOLIA (Fontaine).Thrysopteris brevifolia Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 121,pi. 24, figs. 5, 10.?Fontaine, in Ward, 19th Ann. Kept. U. S. Geol. Surv., pt.2, 1899, p. 660, pi. 161, figs. 10-15.Thrysopteris dentata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 121,pi. 24, figs. 4, 6, 7, 9; pi. 25, figs. 1, 2.Thrysopteris pachyphylla Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 135, pi. 50, fig. 3.Thrysopteris nana Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 141,pi. 56, figs. 4, 8.Thrysopteris heterophylla Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 142,pi. 58, fig. 3.Thrysopteris sphenopteroides Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 143, pi. 58, fig. 6.Thrysopteris squarrosa Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 143,pi. 59, fig. 3.Thrysopteris retusa Fontaine, Monogr. U. S. Geol. Sui'v., vol. 15, 1890, p. 144,pi. 59, fig. 10.Description.?Frond small, bipinnate or tripinnate. Rachisesrather slender, often winged. Pinnae alternate to subopposite, rela-tively long and narrow, divided below, pinnatifid distad. Pinnulesmuch narrowed at the base, decurrent, obliquely toothed or divided,the extent depending upon their position on the frond, triangularovate to lanceolate in outline. Veins somewhat fiabellate, once ortwice forked or simple. Texture coriaceous.This species is not common in the Potomac and is confined to thebasal beds in the Virginia area, although it has also been reportedfrom the Lakota formation in the Black Hills region and from theKootenai formation of Montana. It is represented in the Vu'giniaarea by quite a large number of mostly fragmentary specimens show-ing slight variations in the character of the pinnule lobes or teethwhich were made the basis for distinguishing eight species by Prof.Fontaine. It is possible that more than one type is included in thespecies as defined by the writer, the nature of the material renderingcertainty out of the question; but if the test of the validity of aspecies be the possibility of its being recognized a second time byeither the original author or other students it must be adrcitted thatthese eight so-called species are not good species.Onchiopsis hrevifolia dift'ers from OnycMopsis goepperti and psilo-toides principally in the smaller fronds, less robust pinnules, whichare also less ascending, and in the much less elongate character of thepinnas and especially the pinnules. It is a much smaller and lessrobust form than OnycMopsis latiloha, from which it is readily dis-tinguished, but approaches somewhat close to Onycliiopsis nervosa.
330 PROCEEDINGS OF THE NATIONAL MU8EUM. vol.41.The latter species is on the whole a larger form with less elongateand more triangular pinnge, and the pinnules have more entire mar-gins, the lobes or teeth being rounded and not angular. The veinsare also more numerous.Occurrence.?PATXJXiii^T formation: Fredericksburg, Dutch Gap,Potomac Run, Telegraph Station (Lorton), Virginia.Collections.?United States National Museum.ONYCfflOPSIS PSILOTOIDES (Stokes and Webb) Ward.Hymenopteris psilotoides Stokes and Webb, Trans. Geol. Soc. London, ser. 2, vol. 1,1824, p. 424, pi. 46, fig. 7; pi. 47, fig. 2.Sphenopteris mantelli Brongniart, in Mantell, Illus. of the Geol. of Sussex (rev. ed.),1827, p. 55, pi. 1, figs. 3a, b; pi. 3, figs. 6, 7; pi. 3^, fig. 2.?Schenk, Palaeont.,vol. 19, 1871, p. 208, pi. 23, fig. 1-8; pi. 4, fig. 6 (?); vol. 23, 1875, p. 158,pi. 28, fig. 12.?Heer, Contr. Flora Foss. Portugal, 1881, p. 12, pi. 11, figs.1-5; pi. 12, figs. 2b, 266.?Fontaine, Monogr. U. S. Geol. Surv., vol. 15,1890, p. 91, pi. 1, figs. 1, 2.?Saporta, Flora foss. Portugal, 1894, pp. 72,124, 157, pi. 15, figs. 8-12; pi. 18, fig. 5; pi. 23, figs. 1, 2, 8; pi. 28, fig. 2;pi. 29, fig. 1; pi. 30, figs. 9, 10; pi. 31, figs. 1, 2.Onychiopsis mantelli Seward, Wealden Flora, pt. 1, 1894, p. 41, figs. 4, 5 on p. 50;fig. 6 on p. 52, pi. 2, fig. 1; pi. 13, figs. 1-4; Flora Weald, de Bernissart,1900, p. 15, pi. 1, figs. 17-19; pi. 2, figs. 20, 21; Ann. S. Afr. Mus., vol. 4,1903, p. 5, pi. 1; pi. 5, fig. 1.Thyrsopteris insignis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 127, pi.39, fig. 4; pi. 40, fig. 1; pi. 41, fig. 6; pi. 43, figs. 1, 2, 4; pi. 53, figs. 1, 3.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906, p. 521.Thyrsopteris insignis angustipennis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890,p. 128, pi. 43, fig. 2.Thyrsopteris angustifolia Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 131,pi. 44, fig. 4; pi. 45, fig. 3; pi. 48, fig. 2; pi. 49. figs. 3, 4; pi. 55, fig. 2; pi. 58,fig. 8.?Fontaine, in Ward, Monogr. U. S. Geol. Sur., vol. 48, 1906, p. 516.Thyrsopteris microphylla Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 151,pi. 45, figs. 1, 2, 4, 5.Thyrsopteris rarhiervis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 123,pi. 26, figs. 6, 7; pi. 43, figs. 4-6; pi. 44, figs. 1, 2, 5; pi. 49, fig. 2; pi. 169,figs. 6, 7.?Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol. 48, 1906,pp. 225, 484, 491, 514, 517, 518, 519, 521, 528, 548, 558, pi. 65, figs. 2-4; pi.113, figs. 2, 3.Thyrsopteris dentifolia Fontaine, in Ward, 19th Ann. Kept. U. S. Geol. Surv., pt.2, 1899, p. 660, pi. 161, figs. 6-9.Onychiopsis psilotoides Ward, in Fontaine, in Ward, Monogr. U. S. Geol. Surv., vol.48, 1906, p. 155 (name only).
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Fontaine, in Ward, Monogr., U. S. Geol.Surv., vol. 48, 1906, pp. 506, 518, 528, pi. Ill, fig. 4; pi. 113, fig. 1.?Knowlton, in Diller, Bull. Geol. Soc. Amer., vol. 19, 1908, p. 380.Description.?The following description was given by Seward in1894:Frond tripinnate, ovate lanceolate, rachis winged and prominent; pinnae lanceolate,alternate, approximate, given off from the main rachis at an acute angle. Pinnulesalternate, narrow, lanceolate acuminate, uninerved, of nervation type Coeopteridea(Luerssen, in Rabenhorst 'a Krypt. Fl., vol. 3, p. 11); the larger ones serrate andgradually passing into pinnae with narrow ultimate segments. Fructification in theform of sessile or shortly stalked linear ovate segments with rugose surfaces, and ter-minating usually in a very short awn-like apical prolongation.
NO. 1862. FOSSIL FERNS FROM THE POTOMAC GROUP?BERRY. 331This species is not nearly so common in the Potomac as is Onycliiop-sis gmi^perti, although it appears to have a wider range and be morecommon abroad. It occurs at all horizons in the Potomac, however,a vertical range which is paralleled by its range from the Valanginianthrough the Urgonian into the Albian of Portugal. Elsewhere inEurope it has been found in the Wealden of England, Belgium, andGermany, the Neocomian near Quedlinburg, Saxony, and in theUrgonian of Austria. Forms wdiich are identical, according toSeward,^ are found in the Uintenhage series of South Africa. Inthis country outside of the Potomac it is found in the Kootenai atGreat Falls, Montana, in the Shasta beds of California, and in theLakota formation of the Black Hills.The forms identified as this species from the supposed Jurassicnear Cape Lisburne, Alaska, have been shown by Knowlton to beforms of Diclcsonia. Saporta in his treatment of the Portugueseforms leaves them in the genus Sphenopteris but thinks that theyare more closely related to certain modern species of Davallia thanto OnycMum. His figures, however, do not bring this out with anydegree of certainty. Professor Seward, in discussing specimensfrom South Africa,^ unites with this species the Japanese Jurassicand Cretaceous forms designated as Thyrsopteris elongata Geylerand OnycMopsis elongata Yokoyama. The reason for the proposedchange is the discovery in the English Wealden of more extensivematerial which showed the psilotoides type of pinnule apically andthe elongata type of pinnule proximally. It is quite possible thatthe remains from the English Wealden are all one species, but itcertainly does not follow that the synonymy follows such a disposi-tion. The American remains identified with the elongata type showthat the forms with broader segments are not basal portions offronds with the distal characters of psilotoides, although there is inmost ferns more or less diminution in size upward. Through thekindness of Professor Yokoyama the writer has received specimensof 0. elongata from the Jurassic of Kaga, Japan, and these are cer-tainly specifically distinct, especially in the fertile pinnee, from theEnglish forms of psilotoides. They are, therefore, included in thepresent discussion under 0. goepperti, which is retained as a distinctspecies.Occurrence.?Patuxent formation: Fredericksburg, Dutch Gap,Trents Reach, near Potomac Run, Virginia; New Reservoir, Six-teenth Street, District of Columbia. Arundel formation; Lang-don, District of Columbia. Bay View, Maryland. Patapsco for-mation: Federal HiU (Baltimore), Stump Neck, near Wellhams,Maryland: Near Brooke, Hell Hole, Virginia.Collections.?United States National ]\Iuseum.
1 Seward, Ann. S. Afr. Mus., vol. 4, 1903, p. 5.
332 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.41.ONYCHIOPSIS LATILOBA (Fontaine).Sphenopteris laliloba Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 90, pi.35, figs. 3-5; pi. 36, figs. 4-9; pi. 37, fig. 1.?Fontaine, in Ward, Monogr. U. S.Geol. Surv., vol. 48, 1906, pp. 281, 479, 491, 511, 534, 557.Thyrsopteris brevipennis Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 124,pi. 34, fig. 3; pi. 36, fig. 2; pi. 37, figs. 3, 9; pi. 38, fig. 1; pi. 41, fig. 4.?Fontaine, in Ward, 19th Ann. Rept. U. S. Geol. Surv., pt. 2, 1899, p. 662,pi. 162, fig. la.Thyrsopteris divaricata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 125;pi. 37, figs. 5-8; pi. 70, fig. 1.?Fontaine, in Ward, Monogr. U. S. Geol.Surv., vol. 48, 1906, pp. 504, 511, 517, 521.Thyrsopteris crenata Fontaine, Monogr. U. S. Geol. Surv., vol. 15, 1890, p. 127,pi. 39, figs. 1, 2.Description.?Frond large tripinnate; principal rachis very stoutsometimes winged. Leaf-substance thin but coriaceous. Primarypinna? opposite or subopposite with a stout, rigid, rachis, which isoften somewhat flexuous; ultimate pinnae remotely placed, veryshort, decurrent, passing toward the summit of the principal pinnaeor of the frond through lobed pinnules into entire ones. Pinnulessomewhat remotely placed, cuneate at base, those in the lower partof the frond cut more or less deeply into oblong acute to obtuse lobes,passing toward the tips of the ultimate pinnae into lobed pinnuleslike those of the upper part of the frond, and at the tips into ovateor oblong lobes and teeth. In the upper part of the frond they areelliptical, three lobed, or entire. All the pinnules and segments arebroad. The ultimate pinnae and the pinnules of the lower part ofthe frond usuall}' terminate in three lobed segments or in broadelliptical pinnules. The veins are copiously branched, divergingflabellately into the lobes and teeth, and are very distinct and strong,although not coarse.This is a fine, large species, probably arborescent, and quite dis-tinct from the other species of Onychiopsis. It is common through-out the Potomac but rather less abundant in the Patapsco forma-tion than in the older beds. It has been recorded from the Lakotaformation in the Black Hills area and from the Kootenai formationin both Montana and British Columbia. There is some variationexhibited by the various forms referred by the writer to this species,and some of the smaller ultimate pinnae are readily confused withother species of Onycliiopsis.Occurrence.?Patuxent formation: Fredericksburg, Dutch Gap,Telegraph Station (Lorton), Virginia; New Reservoir (?), Districtof Columbia. Arundel formation: Langdon (?), District ofColumbia; Bewley estate (?), Bay View (common), Maiyland.Patapsco formation: Deep Bottom, Mount Vernon, Hell Hole (?),Chinkapin Hollow (?), Virginia; Federal Hill (Baltimore), Maryland.Collections.?United States National Museum, Johns HopkinsUniversity, Goucher College.