310 SOL ART ELL A. 



bilious cause it to resemble Margarita einerea. The body-whorl has 

 a distinct subsutural carina and three well-separated, strong, raised 

 cariiue below it, the fourth forming a peripheral keel ; sometimes 

 smaller intermediate ones occur between the third and fourth, and 

 two or more smaller ones below the periphery ; in some examples 

 distinct incised spiral lines cover the whole of the base and inner 

 surface of the umbilicus, while a strongly-marked carina, with a 

 deeper groove each side of it, defines the umbilicus. Transverse un- 

 dulations are usually well marked on the upper whorls, and some- 

 times on the base. There are no lamellose lines of growth, so 

 characteristic of M. cinerea ; and the umbilicus is much larger than 

 in the latter. ( Vcrrill.) 



O/ Martha's Vineyard, in 146 to 335 fins. 



Var. L^EVIS Friele. PL 66, figs. 94, 95, 96. 



Shell thin, light flesh-colored, having a taint tinge of mother-of- 

 pearl luster, broad coniform ; 5 tumid whorls, of which the ultimate 

 one is frequently somewhat flattened on the lower surface ; forming 

 thus, a faint angular margin below the periphery ; the spire short 

 but pointed ; suture deep ; the aperture oblique, oval ; the outer lip 

 sharp; umbilicus somewhat wide, and deep. The sculpture some- 

 times shows only faint lines of growth, and is otherwise perfectly 

 smooth ; sometimes there are indistinct indications of spiral grooves. 



Alt. 6, diam. 62 mill. (Friele.) 



Arctic Ocean, East of Greenland, 300-350 fins. 



S. Icevis FRIELE, Norwegian North-Atlantic Expedition, Moll., ii, 

 p. 30, t. 12, f. 4, 5, 6, 1886. 



The species included in this genus appear to be, in a very great 

 degree, polymorphous; and although this beautiful smooth form is 

 so very unlike all the others of the genus known, yet I am not 

 certain but that transitions to Sol. obscura Couth, will be traceable- 

 The traces of spiral sculpture appearing on a couple of specimens 

 of S. Icevis would appear to indicate this. (Friele.) 



Var. BELLA (Verkriizen) Sars. PI. 64, figs. 57, 58. 



Shell rather solid, white, pearly, globose-conoid, the spire moder- 

 ately produced ; whorls 5, subangular, regularly increasing, the last 

 less depressed than in M. obscura, separated by a distinct, scarcely- 

 impressed suture ; aperture dilated beneath, and distinctly angulate ; 

 outer lip thin, irregularly indented, inner lip incurved; umbilicus 

 large, deep, circular, its margin lightly defined ; surface with rather 



