FOSSIL PLANTS. 
387 
think, demonstrates that all the leaflets represented in our plate viii, fig. 1 to 
6, belong to the same species. The cyclopteroidal leaflets of this species vary 
in size from little more than half an inch to four or five inches in diameter. 
«. 
Neuropteris inflat a, Lesqx. 
Geol. Rep. of Ill., vol. ii, p. 431, PI. xxxvii, fig. 2. 
Though a few specimens of this species have been found in the concretions 
of Mazon creek since its description was made, these specimens do not indicate 
in the nature and characters of this plant anything more than was formerly 
known. All these specimens have only two basilar ? round inflated leaflets, 
of a thick coriaceous substance, without any traces of lateral branches. One 
of the specimens has the leaflet of one side lacerated, or cut in lanceolate linear 
laciniae, much like the leaves published in the Geol. Report of Penna., p. 856, 
PI. v, fig. 5, as Cyclopteris Germari , Gopp? As the specimen which I con¬ 
sidered then (1854, Bost. Soc. of N. H.) as referable to Goppert’s species, is 
not in my possession, I cannot, by comparison, ascertain if it is or is not iden¬ 
tical with ours. Moreover, as both the European and the American species 
are founded on mere fragments of specimens, we must consider the species 
which they represent as still uncertain or doubtful. 
Neuropteris coriacea, Sp. nov. 
PI. viii, fig. 7 and 8. 
We have of this species only a small branch in a concretion 
from Mazon creek. It is part of a secondary pinna, lanceolate 
in outline, bearing nearly opposite oblong lanceolate obtusely 
pointed pinnules, turned upwards at an acute angle to the ra- 
chis, and gradually diminishing in size to the terminal leaflet, 
which appears proportionally broad. As it is broken from the 
middle upwards, its form is unknown. The texture of the 
leaflets is thick, and the smooth epidermis is inflated along the 
veins and veinlets in an irregular manner, as seen in fig. 8, 
enlarged. 
This inflation may be caused by groups of spores or elongated sori, placed 
along the veins which are twice forked, and along their divisions. A swelling 
