218 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.54. 



contrary of those which obtain in Latisipho, of which numerous spe- 

 cies exist in the Bering Sea region, and which are contrasted with 

 typical Colus by their buccinoid form and strongly recurved short 

 canal. 



This group is related to Colus much as Latifusus is to Plicifusvs. 



Curious zigzag ridges, not very prominent, appear bohind the 

 shoulder of the last whorl in some specimens of this species, but 

 are absent in others. No explanation of them is obvious, but I 

 suspect them to be pathologic. 



Subgenus Anomalosipho Dautzenberg and Fischer. 



AnomalosipJio Dautzenberg and Fischer, Res. Camp, scientifiques de 

 Monaco, livr. 37, 3912, p. 99. 



Shell solid, of moderate size, the nucleus unknown, the sculpture 

 exclusively spiral, the sutures not constricted, the aperture shorter 

 than the spire, the canal very short, wide, hardly differentiated from 

 the aperture. 



Type. — Sip ho verkruzeni Dautzenberg and Fischer (not Kobelt) = 

 Coins dautzenbergii Dall. Atlantic Ocean ; Grand Banks. 



The Sipho verkruzeni, var. plicata figured by Brogger and cited 

 in the work of Dautzenberg and Fischer, appears from the excellent 

 figure to be probably a young specimen of Plicifusus arcticiis Philippi. 

 Tritonofusns adonis Dall, and Euthria oonulus Aurivillius, are mem- 

 bers of this subgenus, but all specimens yet seen have the apices of 

 the shell eroded so that the nuclear characters are unknown. The 

 radula appears to have normally three cusps on the rhachidian tooth 

 and four on the laterals, but one or more cusps are sometimes defi- 

 cient, according to Aurivillius. 



Genus SIPHONORBIS Morch. 



Siphonorbis Morch, Journ. de Conchyl., vol. 17, 1869, p. 397. No type 

 cited. (First species, Fiisns lachcsis Morch). — Fischer, Manuel de 

 Conchj'l., 1884, p. 624. Type selected, S. ehur Morch, Greenland seas. — 

 Dall, Proc. U. S. Nat. Mus., vol. 24, No. 1264, p. 522.— Dautzenberg 

 AND Fischer, Res. Camp. Scientifiques de Monaco, livr. 37, 1912, pp. 82. 

 93 (Fitsvs ehur Morch). 



TurrisipJio Dautzenberg and Fischer, Res. Camp. Scientifiques de Monaco, 

 livr. 37, 1912, pp. 82, 97. Type, S. lachesis Morch. 



Nucleus siphonorbitoid as before herein described ; shell generally 

 like Coins, but variable: the canal usually short; the sculpture, if 

 any, spiral; the spire varying in relative length compared with the 

 aperture; the operculum as in Colus; the rhachidian tooth with a 

 single cusp, the laterals with two cusps; otherwise as in Colus. 



