ARNOLD — THE PALEONTOLOGY AND STKATICiKAl'Hl' OF SAN PEDRO. 307 



Common in the lower San Pedro series of Deadman Island, and in upper San 

 Pedro series of Deadman Tslaiui, San Pedro, Los Cerrilos, Long Beach, and Crawfish 

 George's. Found in the Pleistocene at Twenty-sixth Street and Pacific Beach, 

 San Diego. 



Living. — Montei'ey to San Diego (Carpenter): south to Peru (Cooper). 



Pleistocene. — Santa Barbara (Cooper): San Pedro; San Diego (Arnold). 



Pliocene. — San Diego well (Dall): Caloosahatchie beds and Alligator Creek, 

 Florida (Dall and Willcox). 



Miocene. — (Newer) North and South Carolina (Conrad and Holmes): (older) 

 San Domingo (Gabb). 



Genus Galerus Humphrey. 



Shell depressed, subconical, spiral; summit subcentral; aperture very large, basal, with a 

 subspiral broad lamina adhering to the left margin. 



Galerus chinensis Linn, is a characteristic species. 



342. Galerus mammillaris Broderip. 



Galerus mammillaris Brod., Trans. Zool. Soc, 1835, PI. XXIII, fig. 5. Cpr., Brit. Assn. Rept., 

 1S56, p. 323. ^=Calypirea fustigiata Gld., = (?) Ga/enis contortus Cpr. {fide Dall, 

 Proc. U. S. Nat. Mus., Vol. XV, 1892, p. 203). 



Calyplrea mammillaris Brod., Trvon, Man. Conch., Vol. VIll, p. 120, PI. XXXI V, figs. 64-75, 

 78-81, 1886. 



Shell depressed, subconical; whorls flattened, three; apex central, blunt; aperture subcircular, 

 large; a broad lamina begins at ape.x on inner surface and makes a whole turn to the left, reaching 

 nearly to margin; lower part of body-whorl corrugated; surface marked by irregular spiral stria. 



Dimensio7is. — Long. 32 mm.; lat. 30 mm.; alt. 7 mm. 



The specimen described was identified by Dr. Dall. 



Rare in lower Sau Pedro series of Deadman Island and San Pedro; and in 

 the upper San Pedro series at Crawfish George's and San Pedro. 



Living. — Puget Sound to Monterey (Cooper): Santa Barbara to Central 

 America (Carpenter): San Pedro (Williamson). 



Pleistocene. — San Pedro (Arnold). 



Pliocene. — San Diego well (Dall). 



Genus Crepidula Lamarck. 



Shell oval, limpet-like, with a posterior, generally lateral spiral apex; interior with a shelly 

 lamina covering its posterior half 



Crepidula peruviana Lam. is a characteristic species. 



