;),; PALEONTOLOGY OF NEW YORK. 



The callosity of the lip at the lateral angles is a variable feature — being 

 sometimes much thickened, and at other times expanded and moderately 

 thickened, scarcely covering the umbilicus. In casts the inner volutions are 

 more or less distinctly visible, according to the conditions and mode of preser- 

 vation. Casts from the Schoharie grit in eastern New York, from the Upper 

 Helderberg limestone at Clarence, in Erie county, where the shell has been 

 replaced by crystalline matter, and from the same formation at Dublin, Ohio, 

 show no characters for specific distinction. Specimens from the last named 

 locality exhibit the shell in various degrees of preservation. 



The specimens cited in my original description as from Brownville, Ohio, 

 present no differences from those which have more recently come into my 

 possession from the Dublin locality. This appears to be identical with the 

 species described by Mr. Meek as B. propinquus from the Upper Helderberg 

 limestone of Ohio; and should farther study prove the western form to be 

 distinct from that of New York, this name will be retained. For the purpose 

 of comparison, a cast of the Ohio form is figured on plate 26. The specimen 

 retains the shell on a part of the opposite side, and also the dorsal carina near 

 the aperture, leaving no doubt of its specific relations with figures 7, 8 and 9, 

 of plate 22. 



Formation and localities. This species occurs in the form of casts of the 

 interior, in the Schoharie grit at Schoharie, in the Upper Helderberg limestone 

 at Clarence in Erie county, and in other places in Western New York; and in 

 the same formation at Dublin, Ohio. 



Bellerophon Pelops var. exponens. 



PLATE XXII, FIG. H. 



Bellemphon Pelopx, Hall. Illustrations of Devonian Fossils : Gasteropoda, pi. 25, fig. 4 ( refe r r ed with doubt 



to this species). 



Form robust ; exterior shell unknown. 



In the cast three or more volutions are visible in the umbilicus, each one 

 having about half its depth concealed in the concavity of the succeeding one. 



