214 BELA. ) 



species of the genus seems to have a longer and a shorter form, 

 which often differ decidedly in appearance. This variation, 

 which is also seen in many other genera of spiral shells, is prob- 

 ably, to a certain extent, sexual ; but it is not entirely so, for 

 while the males seem usually to be long-spired, with narrower 

 and flatter whorls, I have also found males among the short- 

 spired ones. Moreover, there are, evidently, geographical races 

 or varieties, as well as irregular individual variations, and pecu- 

 liarities due to injuries of various kinds." 



B. SCHANTARICA, Middendorff. PL 34, fig. 76 ; PI. 30, figs. 96, 



97 ; PI. 29, fig. 56 ; PL 33 ; fig. 70. 



Shell whitish or flesh-white, under a livid olivaceous epider- 

 mis ; smooth, or with fine spiral striae ; aperture violaceous to 

 white. L. 12, diam. 8 mill. 



Norway to Alaska. 



The synonymy is large, including B. gigas (Beck, MS.), Ver- 

 kriizen (fig. 97), B. Isevigata, Dall (fig. 96), and I think B. tenui- 

 lirata, Dall, described as a variety of B. Isevigata, with revolving 

 striae, and afterwards called simplex, by Yerrill, from a specimen 

 dredged, in 365 fathoms, off Martha's Vineyard. B. simplex, 

 Middendorff (PL 29, fig. 56), shell narrower, with longer spire, 

 does not appear to me to present even varietal ditiracters. B. 

 Morchi, Leche (PL 33, fig. 70), is another name for B. gigas as 

 figured by Verkriizen, whilst for a variety diUering in the more 

 produced, curved canal, the typical gigas of Beck, Mb'rch has 

 proposed the name gigantea. Mr. Pali's B. laevigata is much 

 smaller than the type, with shorter spire, and may constitute a 

 geographical race or variety. According to Mr. Dall B. arctica, 



A. Ad., should be added to the synonymy. 



B. BICARINATA, Couthuoy. PL 28, figs. 32-34 ; PL 27, figs. 18, 

 26,31. 



Whorls six or seven, the lower ones obtusely, the upper ones 

 more acutely carinated, upper whorls with riblets on the subsu- 

 tural band, sometimes crossing the carina, becoming obsolete on 

 the body-whorl ; fine revolving striae cross the growth-lines, and 

 give the shell a finely decussated appearance ; a single revolving 

 ridge on the spire below the shoulder-carina, and several, less 



