164 



Fig. 148. 

 Fig. 148. Jlscoceras Newberryi. a, b, side views of two different specimens. 



at four lines above the apex. The other two are first seen on the side, 

 where they seem to be combined and originate from the first in a single 

 suture ; thus united, they ascend the side about four lines, curving 

 slightly backwards: they then separate gradually, and at eleven lines 

 above the apex turn abruptly forwards and cross the ventral side, the 

 greatest distance between them being just at the turn, where they are 

 separated one line. The aperture is not preserved in any of the speci- 

 mens collected. 



This description is founded on the most perfect specimen seen, of which 

 the above Fig. 148, #, is a view of the right side, a little restored. The 

 other three specimens are more or less worn and distorted. From these 

 it seems that all three of the septa are united, or in some way so concealed, 

 in the suture described as the first septum, that they cannot be seen in 

 perfect specimens. The siphuncle is seen in the base or apex of two of 

 the specimens, not quite half way between the centre and the dorsal 

 margin. It is about 1 line in diameter. 



Length of the best preserved specimen 12 lines ; dorso-ventral diameter 

 at the point where the septum crosses the ventral side 7 lines, and at the 

 most ventricose part below 8 lines. Greatest lateral diameter 10 lines. 

 This specimen is from English Head, Anticosti. 



Another specimen from Gemache Bay (fig. 000, 5) is a little longer, 

 and as it is a little worn both on the dorsal and ventral sides, the proportions 

 appear to be somewhat different ; but when perfect they must be very 

 nearly the same. It will be seen by the figure (>) that the upright 

 sutures at first separate, and then seem to unite again. This might 

 constitute a specific difference ; but on account of the worn condition of the 

 specimen, the markings are very obscure, and this appearance may be 

 deceptive. 



In form, this little species resembles A. Canadense, from which it differs 

 greatly in the course taken by the first septum across the ventral side. 



