366 THE CANADIAN NATURALIST. [Oct. 



and slightly-curved tooth on each side, and a very thin non-denti- 

 culated plate in the centre." This statement clearly indicates the 

 existence of a distinct generic group, for which we would propose 

 the name Liomesus with Buccinum Dalei as the type. I have 

 specimens of L. ovoides from Behring's Straits. 



The shells of the genus Buccinum are peculiarly liable to varia- 

 tion both in form and sculpture, and to obsolescence or erosion of 

 the surface-markings. In the following descriptions, the normal 

 form and markings are always given, except wheu otherwise dis- 

 tinctly stated. The identification of imperfect or worn specimens 

 is extremely difficult in this genus. 



Buccinum polare Gray. 



Buccinum polaris Gray, Zool. of Beechey's Voy. (1839), p. 128. 



Shell rather thin, ovate, turreted. Whorls 6-7, strongly and 

 sharply bi-carinated, with the upper carina strongest, forming a 

 prominent .-shoulder to the whorl. Between these two principal 

 carinse there are often one or two others much slighter. The 

 longitudinal folds are regular, oblique, and about fourteen in 

 number to each whorl ; they are prominent near the suture, but 

 become obsolete below the carina of the shoulder, on which they 

 form tubercles. The primary spiral grooves are about thirty-five 

 in number on the outer whorl, nearly equidistant, deep, sharply 

 and squarely cut, and sometimes double, being divided in two by 

 a sharp and narrow ridge. The primary ridges are flat and even, 

 and covered with very minute secondary grooves, about six to each 

 rido-e. Aperture rather narrow, about half as long as the shell, broad- 

 est above, and somewhat contracted anteriorly; outer lip not patu- 

 lous, thin and simple in our specimens. Columellar lip more deeply 

 incurved or excavated above, less oblique and more elongated than 

 in B. glaciale, and with its three folds sufficiently conspicuous. 

 Periostraca short-ciliated on the upper whorls ; perfectly smooth 

 on the outer whorl. 



Length, 2.2 ; breadth, 1.25 inch. 



This description is taken from two specimens, probably imma- 

 ture, dredged by Capt. John Bodgers, of the U. S. North Pacific 

 Expedition, in the Arctic Ocean, north of Behring's Straits. I 

 consider them to be the B. polare of Gray ; — at least I can find no 

 other form agreeing as well with his description as this. Gray's 

 specimens were from Icy Cape. 



The only species with which this is likely to be confounded are 



