HUDSON-RIVER GROW. 
307 
240. 1. BELLEROPHON BILOBATUS. 
Pl. LXXXIII. Figs. 9 a, b, c. 
Reference pag. 184, pl. 40, figs. 3 a, b, c, d, of this volume. 
This fossil is far less abundant, in the Hudson-river group than in the Trenton limestone, 
but still it is seen in nearly every locality where the rocks are well exposed. The shell is 
rarely preserved, and the casts show the small umbilicus very distinctly. This fossil often 
attains a greater size in this group than in the Trenton limestone. The specimens found 
are usually compressed, and it rarely presents the rotundity so common in the limestone. 
Fig. 9 a. A large imperfect specimen. 
Fig. 9 b, c. Lateral and profile view of a smaller specimen, showing the volutions compressed, as in 
some of the varieties from the Trenton limestone. 
Position and locality. This species is rarely seen in the lower shaly part of the group, 
but in the central semicalcareous strata it is of frequent occurrence. Specimens have been 
obtained from Turin, Pulaski, Loraine, and several other localities. 
(State Collection.) 
368. 4. BELLEROPHON CANCELLATUS (n.sp.). 
Pl. LXXXIII. Figs. 10 a, b, c. 
Involute, subglobose; aperture expanded, bilobate; dorsal line subcarinated ? ; surface 
cancellated by fine concentric and longitudinal striae; concentric striae arching on the side 
and meeting at a sharp angle upon the dorsal line; aperture with a sinus in the dorsal 
margin. 
The concentric striae are usually the more conspicuous, the others being scarcely visible 
except under a magnifier. The only entire specimen seen is crushed, so that the oria-inal 
form cannot be clearly defined ; but the marking of the surface is sufficient to distinguish 
it from any other species in the lower strata. 
Fig. 10 a. Lateral view of an entire individual. 
Fig. 10 b. A portion of the surface enlarged, showing the cancellated striaj. 
Fig. 10 c. A fragment of a shell, apparently of the same species. 
Position and locality. The perfect specimen, with one or two fragments of the same 
species, was found at Loraine ; and the small fragment figured, in the partially altered 
shales near Waterford, these being the only localities where it is known to occur. 
(State Collection.) 
39 
