﻿Description of a Star Fish and other Fossils. 



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ions are equal, and hence contrast strongly with the inequality of the 

 first bifurcations. I have been unable to detect an}' evidence of the 

 existence of pinnules in this species. 



GoMPHOCERAS FABERI, U. Sp. 

 (Plate IV.. Fig. 2, lateral view, natural size; Fig. 2a, a transverse section.) 



Shell small, very moderately gibbous; ventral side quite convex, 

 longitudinally, and dorsal side nearly straight. Greatest diameter at 

 the second chamber from the bod}' chamber. Transverse section 

 ovoid. Siphuncle of medium size, and close to the ventral margin. 

 Septa very slightly convex and curving slightly forward over the con- 

 tracted ventral side. Chamber of habitation of medium size, or 

 considerably less than the size of the combined air chambers, and rap- 

 idly contracting toward the anterior end. 



The specimen illustrated shows seven air chambers. These have a 

 length on the dorsal side of 53-100 inch, and on the ventral side of 

 80-100 inch. The lateral diameter of the second air chamber is 76-100 

 inch, and of the seventh, 60-100 inch. The dorso-ventral diameter of 

 the second air chamber is 78-1 00 inch, and of the seventh, 65-100 inch. 



The species was collected by C. L. Faber, Esq., in whose honor I 

 have proposed the specific name. It is either from the extreme top of 

 the hills at Cincinnati, or from Warren county, Ohio, in rocks some- 

 what higher in the Hudson River Group. It has the appearance of the 

 rocks at the latter elevation, but he is not positive at which locality 

 he collected it. 



GoMPHOCERAS CINCINNATIENSE, U. Sp. 

 (Plate IV., Fig. 1, lateral view, natural size; Fig. la, a transverse section.) 



Shell small, moderately gibbous; ventral and dorsal sides convex, 

 longitudinally, the former having the greatest convexity. Greatest 

 diameter at the second or third chamber from the body chamber. 

 Transverse section sub-elliptical. Siphuncle of medium size and close 

 to the ventral margin. Septa very slightly convex and curving a little 

 forward over the contracted ventral side. Chamber of habitation 

 much less than the size of the combined air chambers, and tapering 

 toward the anterior end. 



The specimen illustrated shows nine air chambers. These have a 

 length on the dorsal side of 53-100 inch, and on the ventral side of 

 72-100 inch. The lateral diameter of the second air chamber is 55-100 

 inch, and of the ninth, 40-100 inch. The dorso-ventral diameter of 

 the second air-chamber is 70-100 inch, and of t lie ninth, 45-100 inch. 



This species is distinguished from G.faberi above described, by its 



