12 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. QI 



which are ahnost median on the whorls and evanesce at the sutural 

 sulcus and on the anterior portion of the whorls. These nodules are 

 cusped on the early turns and become broad and well rounded on the 

 later whorls. Of these nodules, 12 occur upon the first four post- 

 nuclear turns, 14 upon the fifth to eighth, 16 upon the ninth, 20 upon 

 the tenth to twelfth, and 25 on the last whorl. In addition to these 

 axial nodules the whorls are marked by closely spaced, slender, sig- 

 moid lines of growth, which have a retractive curve in the sinus at 

 the summit and are protractive anteriorly. The spiral sculpture on 

 the early postnuclear whorls is almost absent, at best merely indicated, 

 but beginning with the fourth whorl and from there on it increases 

 steadily in strength, eventually forming in the sinus at the summit 

 a series of low, flattened cords of which 18 are present between the 

 summit and the anterior termination of the sinus, those near the sum- 

 mit being more broadly and more strongly developed than those on 

 the anterior portion. Anterior to the sinus the whorls are marked 

 by rather wavy subequal and subequally spaced, somewhat flattened 

 spiral threads of which 20 are present on the last whorl. Suture 

 slightly constricted. Periphery well rounded. Base short, well rounded, 

 marked like the spire with 10 spiral cords, which equal those on the 

 spire in strength and spacing. Columella rather long, moderately 

 slender, and marked with the same type of sculpture that character- 

 izes the base. Aperture pyriform, strongly channeled anteriorly, and 

 provided with a broad sinus at the posterior angle, the portion anterior 

 to the sinus being drawn forward as a clawlike element but main- 

 taining the same curvature as the main body whorl. Outer lip thin. 

 Inner lip covered with a thick callus, which extends on to the parietal 

 wall. 



Type. — U.S.N.M. no. 429834, collected at station 96 in 270 to 330 

 fathoms between latitude i8°36' N., longitude 65°o5'3o" W, and 

 latitude i8°37'i5" N., longitude 65 "03' W, It has lost one nuclear 

 turn. The 15 whorls remaining measure : Length, 30.8 mm ; diameter, 

 II. 9 mm. 



U.S.N.M. no. 429818 contains two topotypes obtained from sta- 

 tion 96. 



U.S.N.M. no. 430475 contains three specimens from station 84 in 

 300 to 350 fathoms between latitude i8°32'3o" N., longitude 65° 18' 

 30" W. and latitude i8°39' N., longitude 65° 17' W., one of which 

 served for the description of the nucleus. 



U.S.N.M. no. 430519 contains three additional specimens from 

 station 23 in 260 to 360 fathoms between latitude i8''32'i5" N., 



