BTJCCINUM. 189 



333, 334, 375), B. sericatum, Hanc. (fig. 335),* B. tenebrosum, 

 Hanc. (figs. 336-338, 378). Mr. W. H. Dall adds to the syn- 

 onymy Volutharpa MorcMana, Fischer, a short-spired variety 

 (fig. 379), and B. perdix, Beck, to which I agree, the latter being 

 very probably the same as B. Finmarkianum, Verkruzen (figs. 

 340-342), which is at most a variety. B. Terrde-Novae, Beck, is a 

 large, thin variety, showing traces of plicos, and revolving angu- 

 lations. B. leucostoma. Lischke, an unfigured species from 

 Japan, is very probably another variety of this protean species : 

 it is a large shell, 81 mill, in length, like Terrse-Novse, but thicker, 

 with white lip, etc. B. simplex, Midd., from the Sea of Ochotsk, 

 is also a large shell, the description of which presents no dis- 

 tinctive peculiarities. B. pulchellum, Sars (fig. 339), does not 

 appear to be very different from his figure of Grcenlandicum 

 (== cyaneum, fig. 331). I add a figure of a remarkable shell (PI. 

 87, fig. 617), which Friele calls var. acuta. 



B. JAPONICUM, A. Ad. 



Ovate, fusiform, thin, spire produced, epidermis horny brown, 

 longitudinally plicate and laminate, with acute, revolving lines 

 (about six in the last whorl), base spirally lirate,.lip margin 

 thickened and reflected. Length, 1 inch. 



Okosiri, Sea of Japan; 35 fathoms. 



Unfigured. Probably nearly related to the preceding species. 

 B. Jeffrey sii, E. A. Smith, is another unfigured Japanese species, 

 30 mill, in length; it is described from a single specimen, with 

 the following remarks appended. " This species may eventually 

 prove but a large and fine variety of B. Japonicum, A. Ad. ; but 

 at present I distinguish it with a separate name, since there are 

 several differences which may be regarded as specific. The 

 whorls are only slightly angulated in the middle by the keel 

 which encircles them at that part ; and this keel is undulated, a 



* Mr. E. A. Smith figures the dentition of this form in Ann. Mag. N. 

 Hist., XX, 134, 1877, and as the side plates have three fangs on one side 

 and two on the other, and the epidermis differs, he considers it distinct 

 from B. cyaneum. Mr. Jeffreys, in same magazine, p. 239, calls attention 

 to the variability of the epidermis in northern shells, and mentions that 

 he had examined numerous specimens of sericatum, and had no doubt of 

 their specific identity with cyaneum. The unequal distribution of denti- 

 cles upon the side plates of the radula, is itself sufficient evidence of the 

 little value of this character. 



