E. Billings—New Species of Paleozoic Fossils. 355 
differing from the majority of the species of Hyolithes in its cir- 
cular section, the operculum not divided into dorsal and ventral 
limbs, and in the remarkable system of muscular impressions on 
the interior. Barrande has figured an operculum of the same 
type, differing from this in having only three instead of five 
pairs of impressions. They are, however, arranged on the same 
lan in both the Canadian and Bohemian species.* It is possi- 
le that our species may be a Salterella. 
than the sides. Lower lip uniformly convex, and projecting 
about three lines in a large specimen. Surface with fine striz 
Collected by T. C. Weston at Bic and St. Simon. 
Genus OBOLELLA Billings. 
6 
une 5. Interior of the ventral valve of 0. enlarged about five ayer 
"Ts. aa, the two small scars at the hinge; 
7. Interior of the ventral valv int 
_Inte e of Obolus Apollinis 
Davidson’s “Introduction to the study of the fossil Brachiopoda. 
* Systéme Silurian, &e., vol. iii, pl. 9, fig. 16 H, = fig. 17. 
. The 
England from a figure Thod. Davidson, Esq. F-R.8., of : 
C. Weston. specimen is from t drawn for me by Thos. Devios, troy, X.Y. ot iby T. 
