390 PALAEONTOLOGY OF ILLINOIS. 



GENUS ODONTOPTERIS, Brgt. 



111. Geol. Report, Tol. ii, p. 432. 



ODONTOPTERIS SUBCUNEATA, Bunb. 



PI. viii, fig. 10 and lOb. 



From the specimen figured here from Mazon creek, it is clear that the fern 

 published under this name in the 111. Geol. Report, vol. ii, p. 433, pi. xxxvi, 

 fig. 3, does not belong to this species. It is referable to Odontopteri$ hetero- 

 phylla, Lesqx., loc. cet., p. 433, pi. xxxviii, fig. 2 to 5. The pinnules of Odon- 

 topteris subcuneata, Bunb., are opposite, proportionally longer and narrower, 

 slightly narrowed in the middle, and enlarged to the very obtuse point. The 

 veins are closer to each other ; and as the English author has figured them, 

 they curve downward before coming into the border of the rachis, and descend 

 in fascicules along the somewhat decurrent base of the leaflets. In their lower 

 part and just above the decurrent border, these leaflets are all strongly bowed. 

 The terminal pinnule is broken above the middle ; it is proportionally large, 

 and appears to be oval-obtuse, entire or without any lateral lobe. I owe this spe- 

 cimen, the most perfect known of this peculiar species, to the kindness of Mr. 

 Michael Prendel, of Morris, 111. 



ODONTOPTERIS BRADLEYI, Sp. nov. 



PL viii, fig. 11. 



NOTHING is known of this species but the leaflet, which has 

 been copied in our figure. It is lanceolate pointed, somewhat 

 contracted at its base in a broad pedicel. The veins are 

 closely approached, sharply and deeply marked, dichotomous 

 in ascending, nearly straight from the base, where they be- 

 come parallel. The veins and veinlets of this species are too 

 close to each other and too numerous to admit it as related to 

 0. heterophylla, Lesq., which has its leaflets sometimes pointed. 

 It may be compared only to- Odontopteris acuminata, LI. and 

 Hutt, of the Oolite. 



In concretions from Mazon creek. 



