16 



The following remarks are added to the dcHcription of JV. pseudo- 

 elegans : — " rien de plus facile que de la confondre ext^rieurement avec 

 le Nautilus elegans de Sowerby. En effet les deux especes sont lisses 

 dans le jeune age, et sillonnees a peu pr^s de la meme maniere dans I'age 

 adulte: mais elles sont neanmoins Qntierement differentes. ]je Nautilus 

 pseudo-eleyans se distingue du Nautilus elegans ptCLi' son dos plus large, et 

 surtout par ce caractere invariable, que la siphon est place au tiers 

 interieur de la hauteur de la bouche, pres du retour de la spire, au lieu 

 de I'etre au tiers exterieur ou pres du dos, comme il Test toujours dans le 

 Nautilus elegans." 



As the position of the siphuncle is unknown in the specimen from the 

 Queen Charlotte Islands, the question naturally arises, is it possible to 

 distinguish N. elegans (D'Orb.), N. pseudo- elegans, and closely related 

 species, by any other characters ? Judging Ity the descriptions in Latin, 

 N. elegans would seem to be a thicker and more ventricose shell than 

 N. pseudo-elegans, but the italicised remarks in Frenc}>, and the tigures in 

 the "Paleontologie Frangaise" convey just the opjjosite impression. Sharpe 

 states that N. elegans (D'Orb.) "is the most globose shell of the group, 

 and has the smallest umbilicus," His figure (Cephalopoda of the Chalk 

 Formation, Plate III., fig. 3) is almost an exact portrait of the specimen 

 obtained b}^ Mr. Eichardson, and the dimensions which Sharpe gives of 

 his fossil ("diameter six and a half inches, breadth five inches,") accord 

 remarkably well with those of the present shell. These statements, 

 as well as the impressions conveyed hj the figures, are, however, 

 negatived by the remark that " the two species are so much alike, 

 that the only character to be relied on for distinguishing them is the 

 position of the siphuncle." It follows that the exact specific relations 

 of the Queen Charlotte Island fosssil cannot be ascertained until more 

 perfect examples have been obtained. Blanford says that there are 

 fourteen septa to the whorl in N. elegans, (D'Orb.) and that in N. pseudo- 

 elegans there are twenty in the same space. In the Queen Charlotte 

 Island specimen it is impossible to ascertain whether the septa were 

 originally distant or approximating. ' 



Pictet and Elanford have shown that the position of the siphuncle in 

 certain European and Indian cretaceous Nautili is not invariable in the 

 same species. Some Nautili, also, which agree in the position of the 

 siphuncle, difi'er materially from each other in external form. For these 

 reasons there is a tendency among pakeontologists to regard N. elegans 

 (D'Orb.) and N. pseudo-elegans as varieties of one species. Still, most 

 authorities have ])ronounced themselves in favour of their distinctness, 



