468 
PALAEONTOLOGY OF ILLINOIS. 
inch long. This last character seems to unite this species to Neuropteris Scheuch- 
zeri, Brgt., which the author considers as probably identical with Neuropteris 
angusti-folia. I have lately received from Mr. S. S. Strong, and also in a con¬ 
cretion from Mazon creek, a splendid specimen representing the top of a pinna of 
Neuropteris hirsuta, Lesq., in the process of unfolding, or still curved in spiral, 
whose leaflets, very hirsute on one side only, are narrow, linear lanceolate, and 
unequal at base, exactly like the leaflets of N. angusti-folia, Brgt. I am, 
therefore, not yet satisfied that this last species is a distinct one, and still believe 
that it may represent a form of N. hirsuta, as it has been explained, Geol. Kept. 
Penn., p. 857. 
Concretions of Mazon creek; from Mr. Even. 
Neuropteris crenulata, Brgt. 
Foss. Flor., tab. 64, fig. 2. 
I refer with doubt to this species a specimen procured by Mr. S. S. Strong 
from the concretions of Mazon creek. It represents the upper end of a pinna 
bearing oblique, oblong, obtuse leaflets, attached to the rachis by the narrowed 
base, forming a broad pedicel, and of the same form as those figured by Brong- 
niart. The upper leaflets are simple, the lower ones compound, or bearing on 
each side at their base a round, small, cyclopteroidal pinnule. The medial 
nerve of the leaflets is obscurely inflated, the veins and veinlets are distant, 
arched, distinct, not inflated, forking once or twice; the borders are slightly 
crenulate by a contraction of the epidermis at the point of the veinlets. Our 
specimens agree well enough with some of this species obtained from Pennsyl¬ 
vania, as also with the description of the author. There is, nevertheless, a dif¬ 
ference especially marked by the division of the inferior leaflets with small 
round pinnules at the base, like those of Neuropteris hirsuta, a division which 
has not been heretofore noticed in this species. The teeth of the borders are 
also less prominent and distiuct on our own specimen. 
Callipteris Sullivantii, Lesqx. J_ 
Ill. Geol. Rep., vol. ii, p. 440, PI. 38, fig. 1. 
Some specimens, in concretions from Mazon creek, show the lower divisions 
of the pinnae more elongated, and pinnately cut-lobed,as in species of Alethop- 
teris. This kind of subdivision would therefore indicate the place of this spe¬ 
cies in this last genus, as admitted by Schimper, Paleont. Veget., p. 561. But 
the peculiar nervation of this fine fossil fern, which is half neuropteroidal, has 
