﻿476 



bic stage than in the specimens in the museum at Ottawa, but the 

 sides are rounder at the stages of growth observed. 



The siphuncle is similarly situated and somewhat smaller than in 

 insolens. 



The diameter of the largest and most perfect specimen was about 

 150 mm. The transverse diameter of the fourth whorl at the 

 whole diameter of 75 mm. was 42 mm., and the ventro-dorsal 25 

 mm. The diameter of the siphuncle at this stage was 4 mm. 

 The diameter of this organ increased slightly to the living cham- 

 ber, but probably did not exceed 6 or 7 mm. On the last quarter 

 (probably of the fourth whorl), just before the living chamber was 

 reached, the siphuncle was found to be misplaced, as is not uncom- 

 mon in species from this locality. This organ has very thick walls 

 and often maintains its form and proportions when unsupported by 

 the septa, although thrown out of place by the movements in the 

 matrix, as happened in this case. It is thrown over to the left and 

 arches towards the venter rising above the centre. The specimen 

 being excavated, however, it was found to be in its usual place, 

 a few septa younger than the point at which it appeared. The 

 entrance into the living chamber was not, however, satisfactorily 

 observed, the septum being broken by compression, although the 

 entrance seemed to be in the usual place, between the centre and 

 the dorsum. The septa were about 6 mm. apart as measured on 

 this siphuncle. 



The shell was very thick near the aperture, which was similar to 

 that of insolens, but appeared to have a narrower hyponomic sinus 

 than in that species. The way in which the lateral crests run for- 

 wards to the lines of involution indicate that there was a crest on 

 the dorsum also, but this could not be observed. 



LlTOCERES INSOLENS (?). 



Nautilus insolens (?) Bill. (Pa/. Foss., i, p. 258). PL vi, Figs. 

 9-1 1, nat. size. 



Loc, Gargamelle Cove, W. Coast Newfoundland. 



This species is so similar in dimensions and characteristics to the 

 one described by Billings and was found so near his locality that 

 I have ventured to apply the same name, although he does not dis- 

 tinctly state whether the siphuncle was dorsad or ventrad of the 

 centre. 



