I40 SMITHSONIAN MISCELLANEOUS COLLECTIONS [vol. 50 



Genus PLEUROTOMELLA Verrill 

 PLEUROTOMELLA SIMPLICISSIMA Dall, n. sp. 



Shell small for the genus, smooth, polished, pale straw-color over 

 a chalky substratum, with about six whorls ; nucleus eroded, sub- 

 sequent whorls turriculate with an angular shoulder ; suture distinct, 

 not appressed, the whorl in front of it to the shoulder flat, below the 

 shoulder moderately rounded ; incremental lines visible but feeble ; 

 under a lens obsolete irregular spiral lines are perceptible, but to the 

 naked eye the shell seems smooth ; aperture narrow, the anal sulcus 

 wide and shallow, beginning at the suture and extending to the 

 shoulder, after which the outer lip is roundly arcuate forward, reced- 

 ing later to the canal ; aperture milk-white, a slight glaze on the body 

 and pillar ; columella short, straight, obliquely truncate in front ; 

 canal short, wide, not recurved, outer lip thin, sharp. Lon. of shell, 

 25; of last whorl, 16; of aperture, 11. 5; maximum diameter, 9 mm. 

 Operculum absent. 



Station 5050, in 1800 fathoms, northeast of Yesso, Okhotsk Sea, 

 September 29, 1906. U. S. Nat. Mus., 110,442. 



A very simple yet pretty form, which is probably a Pleurotomella. 



Genus BUCCINUM Linne 

 BUCCINUM STRIATISSIMUM Sowerby 



Bucciniun striatissimum Sowerby, Ann. Mag. N. Hist., ser. vn, vol. iv, p. 

 370, fig. 1, November, 1899. 



This fine species is rather abundant in the dredgings, having been 

 obtained on the south coast of Yesso, Tsugaru Strait, the Sea of 

 Japan, and the southwest coast of Korea, in from 50 to 568 fathoms. 

 Until the series was compared I was inclined to suspect that this 

 species was identical with the following one, but a study of the series 

 leads me to conclude that, though extremely similar in surface char- 

 acters and general appearance, the present species can always be 

 distinguished by its rounder whorls and more deeply constricted 

 sutures. It reaches a length of some 120 and a diameter of 65 mm. 



BUCCINUM BAYANI Jousseaume 



Tritonium bayani Jouss., Bull. Soc. Zool. cle France, vin, 1883, pi. x, fig. 

 5, "Japan." 



This species is less common than the former, but was obtained 

 from half a dozen stations in the Sea of Japan, and on the coast of 



