246 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Dec. 16, 



affinity from those recent Ferns to which they have most likeness in 

 outline and veining. 



I have scarcely seen a genuine Neuropteris from any formation 

 more recent than the Triassic age. The beautiful and curious fern 

 from the coal-field of Richmond, Virginia, which I described * under 

 the name of Neuropteris linncecefolia, can hardly be considered as 

 properly belonging to this genus ; its leaflets have no trace of midrib, 

 nor has it the general appearance of a Neuropteris. It agrees better 

 with the technical characters of Cyclopteris or Adiantites ; but it 

 appears to have no very close natural affinity to any other fossil Fern 

 yet known, and will probably hereafter form the type of a new genus. 

 With respect to the age of the deposit in which it was discovered, I 

 learn from Sir Charles Lyell that the most recent observations tend 

 to refer the Richmond coal-field to the Keuper rather than to any 

 member of the Jurassic series. 



The Neuropteris ligata, and N. recentior of the " Fossil Flora," 

 from the Jurassic strata of Scarborough, have evidently nothing to 

 do with this genus, but were very properly referred by Professor 

 Phillips to Pecopteris. Indeed the N. ligata is identical with Pe- 

 copteris denticulata, Ad. Br. The Neuropteris lobifolia, Ph. (N. 

 undulata, L. and H.) is more ambiguous in its characters, and may 

 fairly enough be referred to this genus. It cannot, however, be con- 

 sidered by any means as a characteristic Neuropteris. 



In saying that I do not know of any well-characterized Neuro- 

 pteris from a formation later than the Trias, I purposely leave out 

 of the question the enigmatical Anthracitic formation of the Alps, 

 which many geologists refer to the Liassic period. It contains 

 several forms of Neuropteris, to all appearance identical with those 

 of the Coal-formation. If really Jurassic, it is altogether ano- 

 malous and exceptional in its palseobotanical characters. Since my 

 paper j* on the subject was read before this Society, I have had the 

 opportunity of examining some additional specimens from this Alpine 

 Anthracite deposit, and from a different locality % ; and I must still 

 say of them as I said before, that all which are in a fit state for ex- 

 mination belong to forms elsewhere characteristic of the Coal, while 

 there is an entire absence of all the characteristic Jurassic forms. 

 Professor Heer, after a careful examination of very ample materials, 

 came to the same conclusions § . Until this anomaly be satisfactorily 

 explained, it is evident that we cannot safely rely on fossil plants as 

 certain indications of the age of any formation. 



The five beautiful and rare species of Neuropteris discovered in 

 the Gres bigarre of the Vosges (see Schimper and Mougeot's Mono- 

 graph, plates 36-39), agree perfectly with the artificial characters 

 of the genus, though they may, not improbably, be considerably 

 removed in natural affinity from the Carboniferous kinds || . 



* Op. cit. vol. iii. p. 281. f See Quart. Journ. Geol. Soc. vol. v. p. 130. 



% Namely, from Mont de Lans, in the Department of the Isere. The specimens 

 were shown to me by Dr. Ewald, at Berlin. 



§ See his excellent paper on this subject, translated in Quart. Journ. Geol. 

 Soc. vol. vii. 2nd part, p. 91. 



|| Schimper and Mougeot, Monogr. p. 76. 



