44G PALEONTOLOGY OF NEW YORK. 



are in some degree parallel, but usually a little oblique, to the direction of 

 the septal lines, and covering the entire interseptal spaces.* 



The specimens originally referred to this species have a lateral diameter of 

 eighteen to forty-six mm., the largest measurement being of the incomplete, 

 septate portion of an individual. 



The original specimen, described by Mr. Conrad and figured on plate 71, 

 is an incomplete cast of the chambered portion of the shell, measuring 

 twenty mm. in its greatest diameter. 



This species is very clearly related to G. discoideus, and in som« of its forms 

 it is difficult to make a completely satisfactory separation. In the original of 

 the species, and in others which are associated with it, the septa diverge 

 more rapidly from the umbilical side, making a distinct curve toward the 

 aperture and leaving a low, broad saddle, which is not conspicuous in G. dis- 

 coideus, while the ventral saddle is much higher and more sharply defined. 

 The lateral lobe is deeper, while the ventral lobe scarcely differs from that 

 species. 



In its vertical and horizontal distribution this species has an extensive range. 

 The original specimen cited is from the Moscow shales, and similar forms have 

 been found in the upper part of the Hamilton group in Canada West. A single 

 specimen is known from the calcareous beds in the centre of the Hamilton 

 group, while several well-marked specimens are recorded from the Portage 

 group. , 



Formations and localities. In the Hamilton shales at Moscow, on the shores 

 of Seneca lake, at Pratt's Falls, N. Y., and in the same formation in Canada 

 West. Other specimens have been obtained from the shales of the Portage 

 group, above Mount Morris, N. Y. 



•This ornamentation of the Interior surface maybe compared with th*t upon the walla of the earlier 

 chambers of the oidiuary Nadtilus, but in the Goniatite they are not cancellated. 



