no. 1823. MOLLUSKS OF THE GENUS CERITHIOPSIS—BARTSCII. 343 



CERITHIOPSIS (CERITHIOPSIS) STEJNEGERI DINA, new subspecies. 

 Plate 40, fig. 7. 



This is the southern representative of 0. stejnegeri, differing from 

 the species in having the sculpture much more strongly pronounced 

 and in being larger. Three specimens are known (Cat. No. 195175, 

 U.S.N.M.) which come from Sitka, Alaska. The type has three 

 nuclear whorls and seven post-nuclear whorls and measures: Length 

 7 mm., diameter 2.6 mm. 



CERITHIOPSIS (CERITHIOPSIS) NEGLECTA C.B.Adams. 



Plate 40, fig. 5. 



Cerithium neglectum C. B. Adams, Ann. N. Y. Lyceum Nat. Hist., vol. 5, 1852, 

 p. 378. 



Shell minute, elongate-conic, dark brown excepting the nuclear 

 whorls, which are white. Nuclear whorls at least four, well rounded, 

 smooth, forming a mucronate apex. Post-nuclear whorls orna- 

 mented with three spiral cords, the first of which is very feeble on 

 the early whorls and even less strong than the other two on the 

 last volution; the second cord is at the posterior termination of the 

 anterior third between the sutures, while the third is a little nearer 

 the suture than the median. The first and second are only about 

 half as far apart as the median and third. In addition to the 

 spiral sculpture, the whorls are marked by retractive axial ribs, 

 which are about as strong as the spiral cords. Of these ribs, 16 

 occur upon the first, 14 upon the second to fourth, 16 upon the fifth 

 and sixth, and 18 upon the penultimate turn. The intersections 

 of the axial ribs and the spiral cords form strong, cusped tubercles. 

 Those on the first spiral cord are the weakest and are well rounded ; 

 those on the second and third are truncated posteriorly and slope less 

 abruptly anteriorly. The spaces inclosed between the axial ribs 

 and spiral cords are elongated pits between the first and second 

 spiral cords, having their long axes parallel to the spiral sculpture, 

 while those between the second and third are strongly impressed, 

 squarish pits. Suture strongly constricted. Periphery of the last 

 whorl marked by a strong, spiral cord, separated from the supra- 

 sutural cord by a sulcus as wide as that which separates the supra- 

 sutural from the median and, like this, crossed by the continuations 

 of the axial ribs, which terminate at the posterior edge of the periph- 

 eral cord. Base moderately long, ornamented with two spiral cords. 

 Aperture irregularly subquadrate, decidedly channeled anteriorly; 

 posterior angle acute; outer lip rendered wavy by the external 

 sculpture, which is apparent within the aperture; columella short, 

 stout, curved, with the free edge reflected; parietal wall covered 



