KO. 2295. NEW NORTH PACIFIC M0LLUSK8~DALL. 309 



conspicuous minutely punctate incised lines, only strong on the very 

 early whorls, obsolete on the last whorl, with wide interspaces crossed 

 by almost microscopic spiral striae; aperture narrow, the canal hardly 

 differentiated, the enamel very dark, only the plaits whitish, the 

 anterior plait feeble, only distinct in the completely adult shell, the 

 other three conspicuous and strong. Height of shell, 29 ; of last whorl, 

 20; of aperture, 15; diameter, 11 mm. U. S. Nat Mus. Cat. No. 

 219648. 



Ty]ie-locality. — San Pedro, California, Ivli-s. Baldridge. 



No special name having been applied to the group of black Striga- 

 tellas of the Pacific coast, although their similarities are so striking, 

 I have proposed the designation Atrimiira (1918). 



STRIGATELLA (ATRIMITRA) DIEGENSIS, new species. 



Shell small, blackish brown, slender, with a whitish nucleus of 

 about three whorls and four subsequent whorls; the initial part of 

 the nucleus very small and forming a blmit apex, the whole nucleus 

 smooth and changing suddenly to the normal sculpture; the latter 

 begins with four rounded, somewhat undulated strong spiral cords 

 with narrower interspaces; on the next whorl the cords have flat- 

 tened out and the much narrower interspaces are channeled; on 

 the subsequent whorls tlie cords become still flatter and wider a,nd 

 the interspaces narrow grooves, occasionally punctate from the inter- 

 section of incremental lines otherwise hardly visible; on the last 

 whorl the grooves arc obsolete on the middle of the whorl, but there 

 are half a dozen fee])le threads on the base and canal; the suture is 

 closely appressed ; aperture narrow, simple, outer lip hardly thickened, 

 body erased, pillar with two prominent and one obscure plait; canal 

 not differentiated; height of shell, 14; of last v/horl, 11; of aperture, 

 8 mm,; diameter 5.5 nmi. U. S. Nat. Mus. Cat. No. 252998. 



Type-localiiy . — San Diego, California; White Collection. 



STKIGATELLA (ATRIMITRA) MEXICANA, new species. 



Shell large, solid, originally black, but the type-specimen is now 

 decorticated and has lost its nucleus; spire acute, of more than seven 

 moderately rounded whorls, the apex defective; spiral sculpture on 

 the early whorls of half a dozen feeble flattish cords with narrower 

 interspaces, stronger near the preceding suture, absent on the an- 

 terior part of the whorl; these continue but less obviously on the 

 last whorl and similar but stronger cords appea,r on the base, the 

 peripheral region remaining smooth; the canal hardly differentiated 

 but slightly recurved, forming a well marked fasciole; pillar with three 

 strong plaits about midway of the aperture; length of shell, 72; of 

 last whorl, 48; of aperture, 35; maximum diameter, 24 mm. U. S 

 Nat. Mus. Cat. No. 274124. 



