Alet. 



12 



Zt'^gJSSS 



Alethopteris nervosa. {Pecopterisnervosa.Brogwt) Les- 



qiiereux, Geol. 

 Pa., 1858, plate 

 18, fig. 3, Za. He 

 does not rede- 

 scribe or refigure 

 itin Coal Flora, P, 

 1880, but alludes 

 to it on p. 199, 

 under Pseudope- 

 coptevis suhner- 

 vosa. — Note that 



JUlhoi'trns nervosa. . PI ■ /d . AUthoptevis UCT- 



nervosa is the European species. See Gceppart's Syst. Fil. 

 Foss., p. 212. — XIII, Abundant in the Anthracite measures at 

 Pottsville, Shamokin, &c., but is very variable ; "• sometimes 

 the leaflets large and acute ; sometimes near the top of the 

 fronds the pinnae are only pinnately lobed, with round, short, 

 entire lobes, oval, obtuse or slightly undulate." But it is all 

 one species, for Lesquereux found all the varieties together in 

 one specimen, proving it to be Brogniart's species. 



Alethopteris ohsciira. See Callipteridium rugosum, XIII. 

 Alethopteris obscura, Lesq. So called because of the diffi- 



' X I// , v# ^5 y^; /-^^ X: c u 1 1 V o f 



making out 

 any second- 

 ary nerves. 

 Geology of 

 Pennsylva- 

 nia, 18 5 8, 

 Vol. 2, p. 

 865, plate 1, 

 figs. 3, 3a. — 



7- v^^^^iPNB^^- / XIII An- 



^^'Hy ^^^^ /S5Z:L thr-acite 

 Coal Measures, Gate Vein, Pottsville. Note. Unique speci- 

 men, and only the upper part of a frond. — See Callipteridium 

 rugosum. 



