132 CALIFORNIA ACADHMY OF SCIENCES. 



lower Sail Pedro series. Foiiiul also in the Pleistocene west of ItaUi-liouse, tSanta 

 Barbara; ami in tlic I'leistocetie of Pacific Peach, San l)icy:o. 



Living. — Catalina Island (Cooper) : Santa Barbara channel (Carpenter) : Pnjjet 

 Sonnd (Arnold). 



Pkiatocene. — Santa Parbara to San Diej^o (Cooper): San Pedro; Saiila P>ai- 

 bara; San Dieiro (.Vrnold). 



/-•/iore/K'. Santa Rosa; Santa Cm/.; Sargent's, Santa Clara Conntj'; Santa 

 Barbara; San Fernando; San Diego well (Cooper): Stanford University (Arnold). 



Miocene. — Oregon; Martinez; Griswold's, San Benito County; Orestima Can- 

 yon, Stanislaus County; Foxin's, Santa liarl)ara County (Cooper): I'oiiil Blakely, 

 near Seattle, Washington (Arnold). 



60. Lucina calif ornica Conrad. 



Lucina californica CoN.,Jour. I'liil. Acad. Sci., Vol. VII, 1837, p. 255, I'l. XX, fig. i. CPR., Brit. 

 Assn. Rept., 1863, p. 642. Gabb, Pal. Cal., Vol. II, 1869, p. 100. Cooper, 7th Ann. 

 Rept. Cal. St. Min., 1888, p. 247. Keep, West Coast Shells, p. 178, fig. 151, 1892. 

 WiLLi.\MSON, Proc. U. S. Nat. Mus., Vol. XV, 1S92, p. 190. 



Shell of medium size, orbicular, only slightly convex, rather thick; umbones depressed, 

 central; surface ornamented with numerous fine, close- set, sharp, concentric lines and very faint, fine, 

 radiating stri;e; lunule small but distinct, deep-set, wholly in right valve; ligament prominent; two 

 cardinal teeth in each valve ; two prominent anterior, lateral teeth in left valve, one in right valve, 

 other laterals small ; muscle-impressions as in L. acviilineata. 



Dimensions. — Long. 31 mm.; alt. 29 mm.; diam. 16 mm. 



Distinguishable from L. acudlineaki by smaller size, close-set, concentric lines, 

 and having the lunule wholly within the right valve. 



Found in the Pliocene of Deadraan Island: in llie lower San Pedro series of 

 Deadraan Island and San Pedro; and rarely in the upper San Pedro .series at Craw- 

 fish George's, San Pedro, Los Cerritos, Deadman Island, and Long Peach. Found 

 also in the Pleistocene at the bath-house, Santa Barbara, and in the Pleistocene of 

 Pacific Beach, San Diego. 



Living. — Santa Cruz to San Diego (Cooper). 



Pleistocene. — Santa Barbara; San Pedro (Cooper) :' San Pedro; Santa Bar- 

 bara; San Diego (Arnold). 



61. Lucina nuttalli Conrad. 



Lucina nuttalli CoN., Jour. Phil. Acad. Sci., Vol. VII, 1837, p. 255, fig. 2, PI. XX. Cpr., Brit. 

 Assn. Rept., 1863, p. 642. Gabb, Pal. Cal., Vol. II, p. 100, 1869. Cooper, 7th Ann. 

 Rept. Cal. St. Min., 1888, p. 247. Keep, West Coast Shells, p. 179, 1892. Williamson, 

 Proc. U. S. Nat. Mus., Vol. XV, 1892, p. 190. 



Shell small, orbicular, only slightly conve.x, thin; umbones depressed, small, central; surface 

 ornamented by numerous sharp, regular, concentric lines and prominent radiating grooves, which are 

 most prominent near the ends, the whole giving a rather cancellated appearance to the surface; lunule 

 small, nearly all in left valve; hinge and interior as in L. californica. 



Dimensions. — Long. 20 mm.; alt. 20 mm.; diam. 10 mm. 



