340 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.40. 



whorls measuring: Length 3.4 mm., diameter 1.3 mm. The nucleus 

 was described from one of four specimens (Cat. No. 195198a, 

 U.S.N.M.) from Whites Point, San Pedro, California. Cat. No. 

 195183, U.S.N.M., contains seven specimens from Monterey, and 

 Cat. No. 195184, U.S.N.M., contains four specimens from San Pedro 

 Bay, California. 



CERITHIOPSIS (CERITHIOPSIS) GALAPAGENSIS. new species. 

 Plate 39, fig. 4. 



Shell minute, regularly elongate-conic, golden brown, with the 

 row of tubercles at the summit of the shell darker. Nuclear whorls 

 five, well rounded, smooth, separated by a well-impressed suture. 

 Post-nuclear whorls moderately rounded, ornamented with three 

 tuberculate, spiral cords, of which the first (which is at the summit) 

 is considerably less strong than the other two; the third is imme- 

 diately above the suture, while the second is considerably nearer the 

 first than the third. The space between the first and second is about 

 half the width of the middle cord, while that between the second 

 and third is equal to it. In addition to the spiral cords, the whorls 

 are marked by axial ribs, which are about equal to the spiral cords 

 in strength; of these ribs, 16 occur upon all but the penultimate 

 whorl, which has 20. The intersections of the axial ribs and spiral 

 cords form prominent tubercles, which are truncated posteriorly and 

 slope gently anteriorly, while the spaces inclosed between them are 

 elongated pits between the first and second spiral cords, having 

 their long axes parallel with the spiral sculpture, and squarish pits 

 between the second and third cords. Sutures strongly channeled. 

 Periphery of the last whorl marked by a channel almost as wide as 

 that which separates the supraperipheral cord from the median and, 

 like it, crossed by the continuations of the axial ribs. Base moder- 

 ately long, concave, marked by a strong spiral cord immediately 

 below the peripheral sulcus, and another almost as strong which 

 encircles the columella at its insertion. In addition to the spiral 

 sculpture, the base is marked by fine, incremental lines. Aperture 

 irregularly triangular, strongly channeled anteriorly, very effuse and 

 angulated at the junction of the basal and outer lip; posterior angle 

 very obtuse; outer lip thin, showing the external sculpture within, 

 rendered sinuous at the edge by the external sculpture; columella 

 moderately long, stout, curved, with the edge reflected; parietal 

 wall covered with a thick callus. 



The type and two additional specimens (Cat. No. 195185, U.S.N.M.) 

 were dredged by the U. S. Bureau of Fisheries steamer Albatross at 

 station 2813 in 40 fathoms, on coral sand bottom, bottom tempera- 

 ture 81°, off Galapagos Islands.. The type is a perfect specimen, 

 having six post-nuclear whorls and measures: Length 2.4 mm., 



