ARNOLD — THE PALEONTOLOGY AND STRATIGRAPHY OF SAN PEDRO. 287 



Young shells look much like certain species of Triton on account of varices. 

 Common in the Pliocene of Deadman Island; rarer in the lower San Pedro series at 

 Deadman Island, and only occasionally found in the upper San Pedro series at 

 Deadman Island, San Pedro, and Crawfish George's. The specimen figured is from 

 tlie Pliocene of Deadman Island, and is now in the collection of Delos Arnold. 



Living. — Straits of Fuca to Monterey; Japan (Cooper): dredged off San 

 Diego (Raymond): Kodiak Island (Snodgrass). 



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

 Pliocene. — San Pedro (Arnold). 



Genus Ranella Lamarck. 



Shell ovate or oblong, compressed, with two rows of continuous varices, one on each side; 

 aperture oval; columella arcuated and ridged, or crenulated; canal short, recurved; outer lip 

 crenated. 



Ranella spinosa Lam. is a characteristic species. 



308. Ranella calif ornica Hinds. 



Rayiella califoryiica Hds., Ann. Nat. Hist., Vol. II, 1843, p. 255; Voyage Sulphur, p. 12, PI. II, 

 figs. 3 and 5, 1S44. Cpr., Brit. Assn. Rept. , 1863, p. 661. Tryon, Man. Conch., 

 Vol. Ill, p. 40, PI. XXI, fig. 32; PI. XXII, fig. 42, 1881. Gabb, Pal. Cal., Vol. II, p. 73, 

 1869. Keep, West Coast Shells, p. 44, fig. 24, 1892. Williamson, Proc. U. S. Nat. 

 Mus., Vol. XV, 1892, p. 211. 



Shell large, broadly fusiform; spire elevated, about one-half length of aperture; whorls five, 

 convex, each with two prominent, rounded, rather reflexed varices, each set forming a continuous 

 varix from apex to base; between varices are one or two prominent rows of rounded nodes, each 

 row having from one to four, and numerous rugose revolving ridges of varying prominence; suture 

 deeply impressed, distinct; aperture subovate; outer lip thickened, ridged, denticulated; inner lip 

 incrusted, the spiral ornamentation sometimes showing through the incrustation; columella curved, 

 flattened, widened ; canal short. 



Dimensions. — Long. 90 mm.; lat. 67 mm.; body-whorl 70 mm.; aperture, including canal, 

 53 mm.; defl. 76 degrees. 



This shell is easily distinguishable by its size and general solid appearance. 

 Rare in the upper San Pedro series of San Pedro; three perfect specimens found; 

 one fine specimen from the upper San Pedro series of Los Cerritos; also found at 

 Deadman Island and Crawfish George's in the same horizon. Found in the Pleis- 

 tocene at Pacific Beach, San Diego. 



Living. — Santa Barbara to Lower California (Carpenter). 



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

 (Arnold). 



Pliocene. — Kirker's Pass. 



