SIPHO. 123 



Undetermined Neptuneee. 



N. DOMINOV^E and N. LAMNTGERA, Valenc. The first said to 

 belong to the group of Fusus bulbaceus, the last to that of F. 



despectus. 



Gulf of Tartary, Mantchuria. 



N. ARGYROSTOMA, Lam. H. and A. Adams' Genera. 



I do not find any species of this or similar name in the Hist. 

 An. sans Vert. 



N. ANGULATA, Gray. 



Shell ovate, acute, smooth, rather solid, brownish white ; the 

 spire elongated, rather longer than the mouth and canal ; apex 

 blunt ; whorls convex, rounded, with five or six subequal narrow 

 elevated spiral ribs. The mouth small, roundish ovate ; the canal 

 short, rather twisted, open. Length, 2*14 inches. 



North Sea. 



Genus SIPHO, Klein. 



This is one of the most perplexing groups that I have 

 studied ; the distinctive characters of the so-called species are 

 comparative only, having mainly reference to the proportions 

 of the shells, color and sculpture being nearly identical through- 

 out. Experience with boreal shells teaches that they are much 

 more liable to variation in form than those of more temperate 

 latitudes : hence the conclusion is irresistable that nearly all the 

 species of Siplio must be relegated to the synonymy eventually. 

 The want of sufficient and authentic material has prevented me 

 from doing this in several instances. The species are confined 

 to the boreal seas of the northern hemisphere. 



* Shell smooth, with revolving strice. 

 S. ISLANDICUS (Chemn.), Auct. PL 51, fig. 291. 



White, under a thin fawn-color or yellowish brown epidermis. 

 Length, 4-5 inches. 



North Sea ; N. Atlantic Ocean to Iceland and Greenland; 



30 to 100 fathoms. 



It is much larger than the next species, 8. gracilis ; is more 

 spindle-shaped, being produced and attenuated towards the base ; 

 the canal is much longer, and in some specimens quite straight ; 



