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seen, it was not in contact at any stage, but the earlier and proba- 

 bly nepionic whorl was not seen. 



The whorls increase slowly by growth, especially in the transverse 

 diameters ; the ventro-dorsal growth is somewhat more rapid, but 

 not sufficiently so to close up the volutions. In the gerontic stage 

 the living chamber begins to depart slightly from the preceding 

 curve of growth, as shown in the drawing (Fig. 5, PL vi). 



The shell is probably smooth. 



The whorls in section are compressed, the dorsum wider than the 

 venter, and the dorso-ventral diameter much larger than the trans- 

 verse, especially in the ephebic and gerontic stages. The abdomen 

 becomes more or less flattened in the last two stages, but is rounded 

 in the neanic stage. The dorsum remains rounded and gibbous 

 throughout all the stages so far as known. 



The sutures have ventral and dorsal saddles and broad lateral 

 lobes in the neanic stage and probably also in the later nepionic 

 stage. After the abdomen becomes flattened, slight ventral lobes 

 are developed in the sutures of the ephebic and gerontic stages. 



The siphuncle is large, propioventran in all the stages observed. 



Aphetoceras boreale, n. s. (PL v, Figs. 15-17, > }i). 

 Loc, Schooner Island (on southeast side), Newfoundland. 



This resembles Aphetoceras Americanum, at the same age, in 

 sutures and form, but the siphuncle is slightly nearer to the venter 

 and the coiling is obviously distinct and the abdomen has not the 

 well-marked, flattened aspect of the former. 



It is doubtful, of course, whether the whorl actually does form a 

 coil in the specimens collected ; but, if it does, the inner whorls 

 were probably more loosely coiled than in Aphetoceras Americanum, 

 since the curvature of this fragment is larger than in any correspond- 

 ing part of Americanum. 



Aphetoceras Farnsworthi. 



Lituites Farnsworthi, Bill, {pars.) (Geo/. Surv. Canada, Pal. i, 

 p. 21, Fig. 24). 

 Loc, Phillipsburg. 



This species probably belongs to a distinct genus, and is cited 

 here provisionally under this name because it may be merely a 

 highly degenerate species of Aphetoceras. It is also coiled in the 

 neanic stage, but apparently the whorls are not in very close con- 

 tact. There are certainly two species, and probably three, usually 



