WEST AMERICAN PYRAMIDELLID MOLLUSKS. 



199 



The type (Cat. no. 206911, U.S.N.M.) comes from San Diego, Cali- 

 fornia. It has seven post-nuclear whorls and measures: Length 4.8 

 mm., diameter 2.1 mm. 



Examinations of the following specimens have been made : 



U.S.N.M. 

 Cat. no. 



No. of 

 speei- 



Station 

 No. 



126626 

 206912 



206911 



Locality. 



San Pedro, California. 



do 



do 



1 I San Diego, California. 

 .....:.. do 



Disposition of 

 material. 



U. S. Nat. Mus. 



Do. 

 Oldroyd coll. 

 Univ. Cal. coll. 

 U. S. Nat. Mus. 



a Type. 



ODOSTOMIA (EVALEA) lO, new species. 



Plate 22, fig. 4. 



Odostomia tenuis Dall and Bartsch, Mem. Oal. Acad. Sci., vol. 3, 1903, p. 287, 

 pi. 1, fig. 14; not Odostomia teyiuis Carpenter, 1856. 



Shell regularly conic, umbilicated, white. Nuclear whorls tleeply 

 obliquely immersed in the first of the succeeding turns, above which 

 only the tilted edge of the last volution projects. Post-nuclear 

 whorls slightly rounded, feebly contracted at the sutures, and very 

 faintly shouldered at the summit. Sutures poorly defined. Periph- 

 ery faintly angulated. Base somewhat inflated, well rounded, nar- 

 rowly umbilicated. Entire surface marked by retractive lines of 

 growth and closely spaced spiral striations. Aperture ovate, some- 

 what effuse anteriorly; posterior angle acute; outer lip thin; columella 

 slender, very strongly curved, slightly revolute, provided A\-ith a 

 strong fold at its insertion. ' 



The type (Cat. no. 56770, U.S.N.M.) and another specimen comes 

 from Santa Rosa Island, California. The type has six post-nuclear 

 whorls and measures: Length 5.6 mm., diameter 2.3 mm. Cat. no. 

 107741, U.S.N.M., two specimens dredged in 6 fathoms, in Santa 

 Barbara Channel. Cat. no. 15316, U.S.N.M., one specimen from 

 San Pedro. UniA^ersity of California has a specimen dredged at 

 station 30, off Santa CataUna Island. 



ODOSTOMIA I EVALEA) PRATOMA, new species. 

 Plate 23, fig. 4. 



Shell elongate-ovate, bluish- white. Nuclear whorls deeply obliquely 

 immersed in the first of the succeeding turns, above wliich only the 

 tilted edge of the last volution projects. Post-nuclear whorls well 

 rounded, strongly contracted at the sutures, wdth a rounded sloping 

 shoulder at the summit. Periphery obsoletely angulated. Base 



