352 PROCEEDINGS OF THE NATIONAL MU^'^EUM. vol.56. 



between the periphery and the base; with four evenly rounded 

 whorls slightly flattened in front of a somewhat oppressed suture; 

 base rounded, the umbilicus closed by a semilunar convex mass of 

 callus not notched above; the aperture lunate, outer lip thin, the 

 the body callous, the pillar lip somewhat thickened; the operculum 

 is white, porcellanous, of about two whorls; height of shell, 14; of 

 aperture, 10; diameter, 13.5 mm. U. S. Nat. Mus. Cat. No. 209295. 

 Type-locality. — ^U. S. Fish Commission station 4423, between 

 Santa Barbara and San Nicolas islands, California, in 216 to 339 

 fathoms, sand. A very neat and characteristic species, ranging 

 from Esteros Bay to the Gulf of California in deep water. 



CRYPTONATICA ALEUTICA, new species. 



Natica russa Dall, Proc. Cal. Acad. Sci., vol. 5, p. 251, 1874, not of Gould, Proc. 

 Boston Soc. Nat. Hist., vol. 7, p. 43, June, 1859. 



This species was long supposed by me to be Gould's russa, but the 

 fortunate recovery of Gould's type indicates that the large Aleutian 

 species requires a name. The rhachidian tooth, Hke that of Bulhus, 

 has a simple cusp, which establishes the subgenus founded on oper- 

 cul a r ch ar acters . 



EUSPIRA ALGIDA Gould. 



Natica algida Gould, Proc. Boston Soc. Nat. Hist., vol. 3, p. 73, Nov. 1848. 



The fact that Gould's species was labeled "Rio Negro" has led 

 to the supposition that it is a South American species, but the per- 

 fect agreement of Gould's type with an iUaskan and Puget Sound 

 shell has led me to conclude that this locality, like so many other 

 Exploring Expedition localities, is an error. There is, however a 

 Brazilian form, quite similar, which has added to the confusion. 



EUSPIRA ACOSMITA, new species. 



Shell white with a minutely spirally banded yellow brown perios- 

 tracum and about four whorls, the nucleus defective; suture distinct, 

 the whorl in front of it a little impressed; axial sculpture of fine 

 silk}^ incremental lines; there is no spiral sculpture; aperture semi- 

 lunar, oblique, the outer lip thin, the body with a coat of enamel 

 reflected over the umbilical region in a flat pad as in Cryptonaiica, 

 the pillar lip somewhat thickened; height of shell, 16; of aperture, 

 13; diameter, 15 mm. U. S. Nat. Mus. Cat. No. 207218. 



Type-locality. — U. S. Fish Commission station 3128, off Monterey 

 Bay, California, in 627 fathoms, mud; bottom temperature, 38.9° F. 



When the operculum is known this may perhaps turn out to be a 

 Oryptonatica. 



EUSPIRA MONTERONA, new species. 



Shell of moderate size, of a dark greenish olive color with a whitish 

 base; whorls about five, the nucleus decorticated; the surface 

 smooth except for faint incremental lines, the suture distinct, not 



