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involution and broad lateral lobes, and the invariable ventral lobe 

 of Schroederoceras is replaced by a saddle or nearly straight suture. 

 The type of this genus, when it was first described, were the 

 specimens in Geological Museum at Ottawa identified as Nautilus 

 versutas of Billings, but these appear here as Litoceras Whiteavsi, 

 since there is every reason for supposing that they are not the 

 species described by Billings under the name of versutus. 



Litoceras Whiteavsi. 



Naut. versutum (?) (pars), Bill. (Geol. Can., Pal. Foss., i, p. 



258)- 

 Loc, Point Rich and Gargamelle Cove, Newfoundland. 



Having examined the so-called originals of this species, so far as 

 they exist in the Geological Survey Museum at Ottawa, I have 

 found that none of them came from Billings' locality, Bonne Bay, 

 and none of them agree with Billings' description. Billings' 

 species had ten septa to the inch ; this species has the sutures about 

 one-quarter of an inch apart, a difference showing essential dis- 

 tinction. 



The young on the second whorl has the siphuncle ventrocentren 

 and are slightly costated. These costae disappear before the end 

 of this whorl and the surface is marked only by the lines of growth. 

 The siphuncle also shifts gradually, becoming centrodorsan, but 

 in the adult it does not approximate to the dorsum, remaining 

 nearer the centre than the dorsum. The abdomen is very broad in 

 the later stages, and in the adult the diameter through the abdomi- 

 nal angles is longer than the ventro-dorsal diameter. 



The sides are divergent ; that is, slope inwardly. They are 

 rounded and have no umbilical shoulders, the dorsum being coex- 

 tensive with the contact furrow which covers the abdomen com- 

 pletely. The sutures are sinuous, having well-marked ventral 

 saddles, lateral lobes and probably dorsal lobes, although the latter 

 were not seen. The specimens from which this description was 

 taken were collected at Gargamelle Cove, near Billings' locality, 

 and probably belong to this species, as it is identified by the Geo- 

 logical Survey of Canada. The form of the whorl is not so broad 

 laterally, the chamber of habitation is less than one-half of a volu- 

 tion in length and smaller in every way than in Litoceras insolens. 



A section of the whorl is more like that of insolens in the ephe- 



