346 PROCEEDINGS OF THE NATIONAL MU8EUM. vol.41. 



turn. In addition to the axial sculpture, the post-nuclear whorls 

 bear quite regular, rounded spiral cords, of wliich 3 occur upon the 

 first whorl between the sutures, 4 upon the second, 8 upon the third — 

 where the primary 4 seem to have undergone bifurcation — and about 

 14 upon the penultimate turn. The spiral cords are superimposed 

 upon the axial ribs. The spaces inclosed between the spiral cords 

 and axial ribs are very elongated narrow pits, having their long 

 axes parallel with the spiral sculpture. The sloping shoulder on the 

 whorls extends from the appressed summit to the anterior limit of 

 the posterior fourth of the whorls between the sutures. Suture 

 moderately constricted. Periphery of the last whorl well rounded. 

 Base moderately long, slightly produced anteriorly, marked by 9 

 equal and equally spaced spiral cords, which are considerably wider 

 than the spaces that separate them. Aperture irregularly oval; 

 outer lip slightly tliickened behind the edge, rendered sinuous at the 

 edge by the external sculpture; inner lip decidedly curved and slightly 

 reflected over and partly appressed to the base; parietal wall covered 

 with a moderately thick callus. 



The type and two other specimens (Cat. No. 213687, U.S.N.M.) 

 were dredged by the United States Bureau of Fisheries steamer ^ZJa^ross 

 at station 2813, off Hood Island, Galapagos Islands, in 40 fathoms, 

 on coral sand bottom, bottom temperature 81°. The type has 5 

 post-nuclear whorls, and measures: I^ength 2.5 mm., diameter 1.1 mm. 



ALVANIA ELECTRINA Carpenter. 



Plate 30, fig. 4. 



fDiala eledrina Carpenter, Ann. Mag. Nat. Hist., ser. 3, vol. 3, 1864, p. 478. 

 Shell elongate-conic, golden brown. Nuclear whorls two and one- 

 quarter, well rounded^ smooth. Post-nuclear whorls faintly shoul- 

 dered at the summit, well rounded, marked by low, poorly developed, 

 rounded, almost vertical, axial ribs which are very poorly expressed 

 on the first turn, but slightly better on the remaining ones. Of 

 these ribs, 18 occur upon the second, and 22 upon the penultimate 

 turn. In addition to the axial ribs, the whorls are marked by low, 

 spiral cords which increase in width successively from the summit to 

 the periphery. Of these cords, 5 occur between the sutures on the 

 second and on the penultimate turn. The spiral cords pass regularly 

 over the axial ribs. The spaces inclosed between the spiral cords 

 and axial ribs are narrow, elongated pits, having their long axes 

 parallel to the spiral sculpture. Suture weakly impressed. Pe- 

 riphery of the last whorl well rounded. Base moderately long, evenly 

 and well rounded, marked by three low, broad, rounded, spiral 

 cords which are separated by narrow, incised lines. Aperture 

 obhque, ovate; posterior angle almost acute; outer lip rather thick; 

 inner lip short, strongly curved, reflected over and appressed to 



