ARNOLD— THE PALEONTOLOr.Y AND STRATIOIJAPHY OF SAN PEOKO. 303 



Distinn;iiislial)le by its compactness, angiilated body-wliorl, small chink and 

 angle of deflection. Tiie specinicu described was identified I)y Dr. Dall as probably 

 being of this species. 



Some specimens of L. conipacta in the State Museum collection at Berkeley 

 are labeled L. noliduln. 



Rare in lower San Pedro series at Deadman Island; and in the upper San 

 Pedro series at Los Cerritos and San Pedro. Found in the Pleistocene at Barlow's 

 ranch, Ventura; at bath-house, Santa Barbara; and at Spanish I'ight, San Diego. 



Living. — Vancouver district (Carpenter). 



Pleistocene. — San Pedro; Ventura; Santa Barl)ara; San Diego (Arnold). 



335. Lacuna porrecta Carpenter. 



Lacuna porrecta CpR., Brit. Assn. Rept., 1863, p. 656; Ann. & Mag. Nat. Hist., 3id Ser., Vol. XIV, 

 1864, p. 429. Tryon, Man. Conch., Vol. IX, p. 265, PI. L, figs. 55, 56, 57, 1887. 

 Keep, West Coast Shells, p. 66, 1892. 



Shell small, white; spire not much elevated; whorls three, convex; body-whorl very slightly 

 angulated; suture distinct; aperture ovate; lip etTuse; umbilical chink large. 



Dimensions. — Long. 6 mm.; lat. 5 mm.; body-whorl 5.7 mm.; aperture 4.5 mm.; defl. 

 74 degrees. 



Distinguishable by large umbilical cliink, depressed spire, large angle at apex, 

 and effuse outer lip. 



Three specimens of this species found in the lower San Pedro series at Dead- 

 man Tsland; also found in same horizon at San Pedro; and in the upper San Pedro 

 series at Deadman Island, San Pedro, Los Cerritos, and Crawfish George's. 



Living. — Vancouver district (Carpenter). 



Pleistocene. — San Pedro (Arnold). 



336. Lacuna solidula (Loven) Carpenter. 



Plate VIII, Fig. U. 



Laciaia solidula hoxv.^, Inde.x Moll. vScandin., p. 23 {lesle Cpr., Brit. Assn. Rept., 1863, p. 656). 

 Gabb, Pal. Cal., Vol. II, p. 80, 1869. Trvon, Man. Conch., Vol. IX, p. 266, PI. L, 

 fig. 69, 1887. Cooper, 7th Ann. Rept. Cal. St. Min., 1888, p. 244. Keep, West 

 Coast Shells, p. 66, 1892. Dali., Trans. Wagner Inst. Sci., Vol. Ill, Part 2, 1892, 

 p. 321. Williamson, Proc. U. S. Nat. Mus., Vol. XV, 1892, p. 205. 



Lacuna carinata Gld., Proc. Bost. Soc. Nat. Hist., 1848, p. 75. 



Liltorina pedroana Con., Pac. R. R. Rept., Vol. V, p. 327, PI. VI, fig. 50, 1S56. 



Modelia slriataGMm, Proc. Phil. Acad. Nat. Sci., 1S61, p. 368. 



■Shell small, turreted, thin; spire elevated, subacute; whorls four, rounded, ornamented with 

 fine oblique incremental lines; suture deeply impressed, distinct; aperture large, ovate; outer lip 

 thin; inner lip sharp, effuse, incrusted; small umbilical chink. 



Dimensions. — Long. 10 mm.; lat. 6.2 mm.; body-whorl 7.5 mm.; aperture 5.5 mm.; defl. 

 44 degrees. 



