408 
PALAEONTOLOGY OF ILLINOIS. 
Genus SPHENOPTERIS,,Brgt., Ill. Geol. Rep., vol. ii, p. 435. 
- U Frond tripinnate, primary pinnae lanceolate, curved down¬ 
wards, flexuous; secondary divisions perpendicular to the verru- 
cose, broad, round racliis, linear lanceolate pointed, one to two 
inches long, distinct and somewhat distant alternate; pinnules 
points, evidently indicating the base of scales, or hairs, with 
which the plant was covered, and which are still indistinctly 
seen on some part of the secondary branches. The frond of 
this species was evidently a large one, the pinnae being more 
than six inches long. 
The whole appearance of the plant is like that of some species of Cheilan- 
thcs of our time, especially of Cheilanthes vestita , Schwarz. The species should 
therefore be classed in the genus Cheilantites, Gopp. Nevertheless, the group 
of sori appears to cover the whole under surface of the leaflets, a position 
which is not similar to that of the sori of a Cheilanthes. On shales from 
Morris. 
Spiienopteris gracilis, Brgt. 
PI. xv, fig. 3 to 6. 
Frond bi or tripinnate; primary pinnae or fronds triangular 
in outline, taper-pointed, slender; secondary pinnae linear 
lanceolate, alternate and distant, open, curved upwards, flexu- 
