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PALEONTOLOGY OF NEW YORK . 
This is a strongly marked species, and readily distinguished from any other 
at present known in these formations. It is extremely rare, since, up to the 
present time, but two individuals are known. 
Formation and localities. In the shales of the lower part of the Chemung group 
in Chemung county; and near Ithaca, N. Y. 
The two species of Bellerophon, B. obsoletus and B. repertus, having been 
omitted from the preceding descriptions, are inserted in this place. 
Bellerophon repertus, n. sp. 
PLATE XXVI, FIG. 9. 
Shell subglobose, rounded upon the dorsum, and regularly depressed into the 
umbilicus. Transverse section of one volution subcircular. Body-whorl 
ventricose and gradually expanding. Aperture apparently not expanding 
beyond the regular enlargement of the body-whorl. 
Surface cancellated by fine, regular, revolving and transverse striae. The 
transverse striae curve slightly backward over the dorsum into the mesial 
band. Dorsal band narrow, depressed, well-defined, and crossed by the 
concentric striae which form a distinct sinus. The species is distinguished 
by its regular striate surface, and the narrow depressed mesial band. 
Formation and locality. Hamilton group, shore of Cayuga lake. 
Bellerophon obsoletus, n. sp. 
PLATE XXV, FIG. 15. 
Shell short, broadly subovate or globose, ventricose. Body-whorl regularly 
expanding. 
Surface marked by obscure, lamellose, concentric striae, which make a broad 
retral curve over the dorsum. The only specimen observed is imperfect, 
and preserved as a natural mould in the rock. Its form and surface striae 
differ conspicuously from the other forms of the genus here indicated. 
Formation and locality. From the calcareous sandstone of the Chemung group 
at Nichols, N. Y. 
