FOSSIL PLANTS. 401 



PECOPTERIS SILLIMANI, Brgt., Yeg. foss., p. 353. 



PI. 9C, fig. 5 



This is one of the rarest species of our Coal Measures. The few specimens 

 which I consider referable to it, are small and incomplete ; one of them is from 

 Mazon creek, in concretions of clay iron ore. 



PECOPTERIS BUCKLANDI, Brgt., Veg. foss., p. 319. 



PL 99, fig. 2. 



The specimen representing this species, distinctly shows the character indi- 

 cated by the author. The pinnae are straight, nearly horizontal (four inches 

 long with the end broken off), the leaflets oblong, somewhat lanceolate obtuse, 

 but not quite as obtuse as in Brongniart's figure, slightly scythe-shaped out- 

 wards, etc. The pinnules are of a thick coriaceous substance, concave, and 

 deeply impressed upon the stone. 



Found in a concretion on Little Vermilion river, by Dr. J. C. Winslow. 



PECOPTERIS CANDOLLIANA, Brgt., Veg. foss., p. 305. 



PI. 100, fig. 1. 



One good distinct specimen, in a concretion from Mazon creek, while nume- 

 rous specimens from the same locality have branches, with characters interme- 

 diate between this species and fccopteris cy'athca of the same author. 



PECOPTERIS HEMITELOIDES, Brgt., Veg. foss., p. 314. 



PI. 108, fig. 1. 



The specimen from Mazon creek, is half a concretion, representing part of a 

 pinna, bearing oblong, slightly pointed leaflets, disconnected at the base, with 

 borders inflated, and a double row of large son, unlike any other hitherto seen 

 of this genus. These sori open by a transverse solit, agreeing with Brongniart's 

 fig. 2 A in every peculiarity of form. Our specimen does not show any trace 

 of nervation. 



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