192 CALIFORNIA ACADEMY OF SCIENCES. 



Gabb" as occurring in the Miocene of San Domingo, and living on the Atlantic 

 Coast near Cape Hatteras. Whether or not this species is identical with the West 

 Coast form the writer is unable to state. 



Rare in the lower San Pedro series at Deadman Island. Found in the 

 Pleistocene at Twenty-sixth Street, San Diego. The specimen figured is from the 

 lower San Pedro series at Deadman Island, and is now in the collection of Delos 

 Arnold. 



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



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



Family XLIII. SCAPHANDRID^. 



Genus Cylichna Loven. 



Shell strong, cylindrical, smooth or punctate-striate; spire minute or truncated; aperture 

 narrow, rounded in front; columella callous, with one plait. 



Cylichna arachis Quoy. is a characteristic species. 



151. Cylichna alba Brown. 



Plate X, Fio. 18. 



Cyh'ck?ia cy/ifidracea (non LiNii.) Cpr., Brit. Assn. Rept., 1863, p. 647. Cooper, 7th Ann. Rept. 



Cal. St. Min., 1888, p. 238. 

 Volvaria alba Brown, Illustr. Conch. G. B., p. 3, PL XIX, figs. 43, 44. 

 (3'^'<r//«a a/(5a (Brown) Loven, Ofversight K. Vet.-Akad, Forh., 1846, p. 142. Tryon, Man. Conch., 



Vol. XV, p. 290, PI. LX, fig. 16, 1893. 



Shell small, cylindrical, smooth; spire truncated; aperture narrow posteriorly for about two- 

 thirds length of shell, when the inner lip gradually retracts to the columella, forming a rounded 

 anterior end to the aperture; columella callous, with one plait. 



Dime7is7ons.—\^or\g. 10.5 mm.; ma.ximum diam. 4.25 mm. 



Specimens identified by Dr. Dall. 



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

 series at San Pedro. 



Found also in the Pleistocene at Spanish Bight, San Diego, and at Barlow's 

 ranch, Ventura. The specimen figured is from the lower San Pedro series at Dead- 

 man Island, and is now in the collection of Delos Arnold. 



Living. — Monterey to San Diego (Cooper). 



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

 Ventura (Arnold). 



Pliocene. — San Diego well (Cooper). 



