ARNOLD — THE PALEONTOLOGY AND STRATIGRAPHY OF SAN PEDHO llo 



Subgenus Hinnites Def ranee. 



Shell (up to advanced youth) a typical Ch/amys, later becominjj sessile and irregular, in 

 which stage the resilial pit is elongated and the cardinal mart;iii develops an obscure area. 



Type, Hinnileft cortezi Defr. 



36. Pecten (Hinnites) giganteus Graij. 



Hinnites giganleus Gray, Ann. Phil., 1826, p. 103. Carpenter, Brit. Assn. Rept., 1863, p. 675. 

 Gabb, Pal. Cal., Vol. II, 1869, p. 105. Cooper, 7th Ann. Rept. Cal. St. Min., 1888 

 p. 243. Keep, West Coast Shells, p. 165, fig. 138, 1892. Williamson, Proc. U. S. 

 Nat. Mus., Vol. XV, 1892, p. 193. + H. pouhoni CoNR. = (?) H. crassus CoN., 

 (/</<? Dall, Trans. Wagner In.st. Sci., Vol. Ill, Part 4, 1898, p. 711.) 



Shell large, oval, irregular, inequivalvc, subequilateral; surface sculptured by about seventeen 

 irregular, squaniose, rounded, prominent radiating ridges, with two or three minor ones between each 

 pair of the large ones. 



Dimensions. — Long. 65 mm.; alt. 65 mm.; diam. 25 mm. 



Adults (listliijjuisliable from Pecten on account of distortion caused by attacb- 

 nient to some object during tlie later stages of growtb. Tlie young, nnattacbed sbells 

 of tbis species much resemble the young of P. hastatiis, but are distinguishable from 

 this species by a less spinose growth on the ribs, and also in having a much 

 heavier shell. 



Rare in upper San Pedro series of San Pedro, Los Cerritos, Crawfish George's, 

 and Deadraan Island; a few specimens from the lower San Pedro series of San Pedro. 



Living. — Straits of Fuca to San Diego (Cooper). 



Plei!<toeene. — Santa Barbara to San Diego (Cooper): San Pedro (Arnold). 



Pliocene. — Santa Rosa Island; Ventura County; Los Angeles County (Cooper). 



Family X. LIMID.'E. 



Genus Lima (Bruguiere) Cuvier. 



Shell equivalve, compressed, obliquely oval; anterior side straight, gaping, posterior 

 rounded, usually close; umbones apart, eared ; valves white, smooth, punctate-striate, or radiately 

 ribbed and imbricated ; there is usually a thin, brownish epidermis ; hinge-area triangular, cartilage 

 pit central ; adductor impression lateral, large, double ; pedal scars, two, small. 



Lima squamosa Lam. is a characteristic species. 



Subgenus Lima ■'<. .s. 

 Hinge edentulous; valves gaping, inequilateral. 



Section Mantellura Adams. ^ 

 Submargins not impressed. 

 Type, Lima hians Grael. 



