446 
PALAEONTOLOGY 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 some 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 that upon the walls of the earlier 
chambers of the ordinary Nautilus, but in the Goniatite they are not cancellated. 
