56 FLOKA OF LOWER COAL MEASURES OF MISSOURL 



differ iu the angle aud form of the pinnules, the lobes being much more 

 deeply denticulate, while the nerves are straight and fork in adaptation to 

 a more prevailingly bifid instead of trifid tendency in the system of the 

 division of the lobes. Moreover, 8. liymenopliylloides Brongn. was described 

 from the Oolite of "Whitby, in Yorkshire. 



Our specimens, including the fragments from Missouri, are character- 

 ized especially by the alate pinnules and lobes, bifid in their system of 

 division and traversed by very distinct, strong, straight, rigid nerves. 

 Thus, while it is apparently closely related to 8. Gutbieriana Geinitz^ or 

 8. Picandeti Zeiller,^ it seems to me to be hardly admissible to either. Both, 

 especially the former, have the pinnae more slender, acute, decurrent, and 

 less alate. 8i)henoi)teris Picandeti Zeill. has the ^aimiules narrower at the 

 base, the lobes less often bifid, the nerves more slender. The lower pinnules 

 of the smaller pinna? of 8. canneltonensis are often broadly alate, and except 

 for the sharp teeth, nearly truncate at the broad apex. From the form of 

 the pinnation seen in the segments from Caunelton I suspect that the frond 

 has the mode of division illustrated by Zeiller^ in BipJothmema ZeiUeri Stur, 

 to which our species is obviously very close, probably moi'e closely related 

 than to any other, though in this, too, we seem to have a much more delicate 

 and elongated system of pinnation, the divisions being narrower and the 

 lobes acuminate. Specimens from Cannelton which are perhaps doubtfully 

 separable from 8. canneltonensis were identified by Lesquereux as 8. suhlo- 

 hata Weiss. It is possible that a comparison of specimens or a more 

 complete representation of 8. canneltonensis may prove its identity with 

 the Diplotlimema ZeiUeri Stur. 



For the present, since the American specimens, which deserve further 

 illustration, can hardly be referable to Spheno^Jteris liymenophylloides Brongn., 

 or 8. Gnthieriana Gein., I name them after the locality in Pennsylvania 

 from which the specimen figured by Lesquereux was obtained. This fig- 

 ured specimen. No. 4672 of the Lacoe collection, is thus the type of the 

 Sphenopteris canneltonensis. 



Localities. — Hobbs's coal bank, U. S. Nat. Mus., 5665; a very doubtful 

 fragment is from Owens's bank, U. S. Nat. Mus., 5569. 



' Gutbier, Abdriicke, pi. iv, iig. 13. Geinitz, Verst. Steinkohlenf. Sachsen, p. 15, pi. xsiii, fig. 10. 

 - Fl. foss. houill. Commentry, vol. i, p. 53, pi. ii, figs. 10-12. 



' Zeiller, Fl. foss. hoiiill. Valenciennes, p. 151, pi. xv, fig. 5 ; pi. xvi, fig. 12. Stur, Fame d. Carbon- 

 Flora, p. 329. 



