132 CALIFORNIA ACADEMY OF SCIENCES. 



lower San Pedro series. Found also in the Pleistocene west of bath-house, Santa 

 Barbara; and in the Pleistocene of Pacific Beach, San Diego. 



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

 Sound (Arnold). 



Pleistocene. — Santa Barbara to San Diego (Cooj)er) : San Pedro; Santa Bar- 

 bara; San Diego (Arnold). 



Pliocene. — Santa Rosa; Santa Cruz; Sargent's, Santa Clara County; 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 Barbara County (Cooper): Point Blakely, 

 near Seattle, Washington (Arnold). 



60. Lucina calif ornica Conrad. 



Liicina californica CoN.,Jour. Phil. Acad. Sci., Vol. VII, 1837, p. 255, PI. 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. 

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



Shell of medium size, orbicular, only slightly conve.x, rather thick; umbones depressed, 

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

 radiating strife; 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. acutilineaia. 



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



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

 and having the lunule wholly within the right valve. 



Found in the Pliocene of Deadraan Island; in the 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 Beach. 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 nnttalli 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 convex, 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 Z,. californica. 



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



