300 CALIFOUNIA ACADKMY OF SCIENCES. 



This little animal forms a groove on the surface of shells or stones, and covers 

 it over with shelly matter, forming a tubular case. 



Common on stones and shells of upper Pan Pedro series at San Pedro, 

 Deadman Island, Crawfish (Icorge's, and Los Cerritos. 



Living. — California coast (Carpenter). 



Pleistocene. — San Pedro (Arnold). 



Family LXXII. TURlllTELLlD^. 



Genus Turritella Lamarck. 

 Shell elongated; many whorled; whorls rounded, with revolving stria'; aperture rounded. 

 Turritella terebra Linn, is a characteristic species. 



330. Turritella cooperi Carpenter. 



Turriiella cooperi Cpr., Brit. Assn. Rept. , 1863, p. 655; Proc. Cal. Acad. Sci., Vol. Ill, 1864, 

 p. 216. Gabb, Pal. Cal., Vol. II, p. 80, 1869. Tryon, Man. Conch., Vol. VIII, p. 20, 

 PI. LXI, 1886. CoopKR, 7th Ann. Rept. Cal. St. Min., 1888, p. 269. Keep, West 

 Coast Shells, p. 73, fig. 58, 1892. Dall, Trans. Wagner Inst. Sci., Vol. Ill, Part 2, 

 1892, p. 318. Williamson, Proc. U. S. Nat. Mus., Vol. XV, 1892, p. 205. 



This species is distinguishable from T. jewettii by its deej»ly impressed and 

 distinct suture, faint spiral ridges (lacking entirely in some specimens), circular 

 aperture, and sharper spire, the deflection in this species being only 10 degrees. 

 Resembles Atlantic form, T. apicaliti. 



Rather common in the Pliocene and Pleistocene of San Pedro and vicinity. 

 Found in the Pliocene at Pacific Beach and Russ School, San Diego; and in the 

 Pleistocene at Pacific Beach, San Diego; and at Barlow's ranch and the irrigating 

 ditch, Ventura. 



Living. — Santa Barbara to San Diego (Cooper). 



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

 Ventura (Arnold). 



Pliocene. — San Diego well (Dall): San Pedro; San Diego (Arnold): San 

 Quentin Bay, Lower California (Orcutt). 



331. Turritella jewettii Carpenter. 



I'LATB IV, Fig. l.S. 



Turritella je-wettii CpR., Brit. Assn. Rei)t., 1863, p. 655; Ann. & Mag. Nat. Hist., 3rd Sen, 

 Vol. XVII, 1866, p. 276. Gabb, Pal. Cal., Vol. II, p. 80, 1869. Cooper, 7th Ann. 

 Rept. Cal. St. Min., 1888, p. 269. 



t Turritella sa7igiiinca Reeve, Cooper (Williamson), Bull. No. 4, Cal. St. Min. Bureau, 1894, 

 Part 3, p. 32. 



