NO. 2295. NEW NORTH PACIFIC MOLLUSKS—DALL. 315 



tinct, deep ; axial sculpture of faint incremental lines ; spiral sculpture 

 of a very few hardly visible lines in front of the suture on the upper 

 whorls and near the canal ; beside these there are irregular divergent 

 raised lines on the periphery, such as have been noted in a number of 

 species but which are doubtfully normal; aperture semilunate, outer 

 lip thin, sharp, slightly arcuate, inner lip erased, pillar short, twisted, 

 attenuate in front, axis pervious ; canal wide, short, strongly recurved ; 

 height of shell, 30; of last whorl, 22; of aperture, 15; diameter, 15 

 mm. U. S. Nat. Mus. Cat. No. 205243. 



Type-locality. — U. S. Bureau of Fisheries station 5015, in the Sea 

 of Oldiotsk, in 510 fathoms, green mud; bottom temperature, 35.9° F 



The operculum is normal. 



COLUS (AULACOFUSUS) NOBILIS, new species. 



Shell large, regular, acute, whitish, with a v/arm yellow-brown per- 

 sistent periostracum with eight whorls, exclusive of the very minute 

 (lost) nucleus, separated by a very sharply defined suture, and ele- 

 gantl}' rounded ; spiral sculpture of (on the penultimate whorl about 

 15) flattened revolving close-set cords either in pairs or mediall}^ 

 grooved for the most part, practically uniform over the whole shell; 

 axial sculpture only of fine silky incremental lines; aperture rather 

 wide, the outer lip expanded, thin, more or less crenulated internally 

 by the effect of the external sculpture; body and pillar Vv'ith a thick, 

 continuous coat of enamel; canal distinct, short, slightly recurved; 

 operculum solid, blackish, with apical nucleus. Height of shell, 85; 

 of last whorl, 55; of aperture, 43; diameter, 38 mm. U. S. Nat. Mus. 

 Cat. No. 222983. 



Type-locality. — U. S. Fish Commission station 3484, in Bering Sea, 

 near the Pribilof Islands, in 60 fathoms, mud; bottom temperature, 

 37.4° F. 



COLUS (AULACOFUSUS) OMBRONIUS, new species. 



Shell of moderate size, white with a dull olive gray periostracum, 

 of more than six well-rounded whorls, the nucleus missing, the aper- 

 ture longer than the spire; suture distinct; not appressed; axial 

 sculpture of rather strong, regular and regularly spaced increm.ental 

 lines which minutely corrugate the spirals ; spiral sculpture of (on the 

 penultimate whorl about a dozen) flattish cords, equal and equally 

 spaced with much narrower interspaces; on the last whorl, especially 

 near the peri]3hery, these cords have a tendency to become keeled and 

 the interspaces wider; aperture ovate, simple, the outer lip slightly 

 expanded and reflecting the external sculpture, throat white, inner 

 lip enameled, pillar twisted, almost pervious ; canal two-thirds as long 

 as the rest of the aperture, well recurved, height of shell, 50 ; of last 

 whorl, 37; of aperture, 30; diameter, 21 mm. U. S. Nat. Mus. Cat. 

 No. 213239. 



