WEST AMERICAN PYRAMTDELLID MOLLUSKS. 



181 



whoii well rounded, the latter ornamented by about eleven lirations, 

 which are similar in character to those between the sutures but much 

 less strongly expressed. Aperture rather broad, suboval, somewhat 

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

 short, somewhat curved, strongly revolute anteriorly, having a weak 

 oblique fold at its insertion. 



The type (Cat. no. 16S71S, U.S.N.M.) and nine specimens come 

 from San Pedro, California. It has five post-nuclear whorls and 

 measures: Length 2.9 mm., diameter l..'> mm. 



The following specimens have been examined : 



U.S.N.M. 

 cat. no. 



168718 

 168719 

 168720 

 162677 



No. of 

 speci- 

 mens. 



Locality. 



San Pedro, California 



San Diego, California 



Santa Catalina Island, California 



La Jolla, California 



Arch Beach, California 



San Pedro, California 



Disposition of 

 material. 



U. S. Nat. Mus. 



Do. 



Do. 



Do. 

 Univ. Cal. coll. 

 Oldroyd coll. 



ODOSTOMIA (EVALINA) INTERMEDIA Carpenter. 

 Plate 20, fig. 6. 

 Dunkeria intermedia Carpenter, Cat. Mazatlan Shells, 1856, pp. 435, 430. 



Shell elongate-ovate, white. Nuclear whorls large, two and one- 

 half, forming a depressed helicoid spire, whose axis is at right angles 

 to that of the succeeding turns, in the first of which it is about one- 

 fifth immersed. Post-nuclear whorls well rounded, marked by very 

 much enfeebled indications of axial ribs, which are best shown at the 

 summit of the whorls, and broad low spiral lirations, of which 7 occur 

 between the sutures. Periphery and base of the last whorl well 

 rounded, marked by eight low spiral cords, which are somewhat closer 

 spaced about the umbilicus. Aperture oval; outer lip thin, showing 

 the external sculpture within; columella slender and curved. 



The type and another specimen were taken off Spondylus, at Mazat- 

 lan, Mexico. It has three post-nuclear whorls and measures: Length 

 1.4 mm., diameter 0.7 mm. It is on tablet 2010, Liverpool collection, 



British Museum. 



Subgenus IOL.ffiA A. Adams. 



lolxa A. Adams, Proc. Zool. Soc, 1867, p. 310. =Iole A. Adams, Ann. Mag. 

 Nat. Hist., 3d ser., vol. 5, 1860, p. 300; not lole Blyth, Joum. Asiat. Soc. 

 Bengal, vol. 13, pt. 1, 1844, p. 386. 



Shell umbilicated, marked by spiral cords, and axial riblets which 

 cross the grooves between them. 

 Type. — lole scitula A. Adams. 



KEY TO THE SPECIES OF THE SUBGENUS lOL^A. 



Shell strongly shouldered. 



Shell stout, adult 2.? mm. in diameter nmianta, p. 182. 



Shell slender, adult 1 mm. in diameter eucosmia, p. 183. 



Shell not shouldered dclicatula, p. 183. 



2565— Bull. 68—09 13 



