ARNOLD— THE PALEONTOLOGY AND STKATIORAPHY OF SAN PEDRO. 337 



were found to be recent shells from the kitchen-middens tliat overlie all of the San 

 Pedro fossil deposits. The mistake of reporting kitchen-midden shells as " Pleisto- 

 cene " and " Pliocene " has been made by a number of collectors, who have mis- 

 taken these accumulations for fossil deposits. The two species of llaliotU above 

 referred to, besides H. falgens, are common in many of the kitchen-middens along 

 the coast, and especially so in those around San Pedro. 



Living. — Monterey to Lower California (Carpenter). 



Pleistocene. — San Pedro; San Diego (Arnold). 



Family LXXXVII. FISSURELLID.E. 

 Subfamily FISSURELLIDEIN^. 



Genus Lucapina Gray. 



Shell oval-oblong, conic, depressed, cancellated; summit subcential, the oval opening sur- 

 rounded by a callus; margin crenulated. 



Lucapina crenulata Sbj'. is a characteristic species. 



394. Lucapina crenulata Soiverby. 



Fissurella crenulata Sby., Tank. Catalogue, App., p. vi, 1825; Conch. 111., No. 19, figs. 31, 38, 1831. 



Z,«f<i/>;>w frd-wj^/a/a Sby., Cpr., Proc. Zool. Soc. , 1856, p. 223. Cpr., Brit. Assn. Rept., 1863, p. 651. 

 Gaeb, Pal. Cal. Vol. II, p. 85, 1869. Tryon, Struct, and Syst. Conch., Vol. II, p. 326, 

 PI. LXXXIII, fig. 17, 1883. Tryon, Man. Conch., Vol. XII, PL XLIV, figs. 95, 96, 

 1890. Keep, West Coast Shells, p. 95, fig. 79, 1892. Williamson, Proc. U. S. 

 Nat. Mus., Vol. XV, 1892, p. 198. 



Shell large, oval, conical, depressed; surface cancellated with numerous radiating ridges and 

 concentric incremental lines; summit subcentral, the oval opening surrounded by a callus; margin 

 crenulated. 



Dimensions. — Long. 90 mm.; lat. 57 mm.; alt. 20 mm. 



This species is distinguishable by its large size and rather faint sculpture. 

 Rare in the upper San Pedro series at Los Cerritos. 



Living. — San Pedro to San Diego (Carpenter; Williamson). 



Pleistocene. — San Pedro (Arnold). 



Subfamily EMARGINULINjE. 

 Genus Fissuridea Suuinson. 



Shell oval, conical, depressed, with the ape.x in front of the center, and perforated by oblong 

 opening; surface radiated or cancellated; margin crenulated; callosity often truncate, sometimes 

 aminated. 



Fissuridea incequalis Sby. is a characteristic species. 



( is ) May 4, 1903. 



