20(> I'ALU'dltNIA Al'ADEMV Or SIUICNCEB. 



Pleistocene. — 8aii Dici^o (Cooper): "^ii" IVhIi'o (Cooix-r; Arnold): W'lituia; 

 San Diogo (Aniolil). 



Pliocene. — San Diego (Cooper; Anmld). 



Goiui.-^ Opalia //. .(• ,1. Aihims. 



Shell turriciilated, imperforate; whorls united, the last wiiii :i rib at the base. 

 Opalia coronatd Lain, i-^ a eliaracteristie species. 



[S. D.] Opalia anomala Stearns. 



Ofia/ia anoma/a Stearns, Proc. Phil. Acad. Nat. Sci., 1875, p. 464, PI. XXVII, fig. i. Cooper, 

 7th Ann. Rept. Cal. St. Min., 1888, p. 255. Dall, Trans. Wagner Inst. Sci., Vol. Ill, 

 Part 2, 1892, p. 245. 



Shell solid, imperforate, elongated, conical; spire gradually tapering; whorls conve.x, when 

 perfect probably eleven to fourteen in number, nearly smooth, being marked only by incremental, 

 and, in some specimens, by an outgrowth varix; suture well defined; basal whorl traversed spirally 

 by an inconspicuous rib, varying in prominence, in some si)ecimens barely discernible; the convexity 

 or angularity of the lower part of the basal whorl modified by the presence or absence of the 

 basal rib. 



Dimensions. — Long. 53 mm.; lat. 19 mm.; body-whorl 24.5 mm.; a|)frturc 11 mm. 



Tlii.s large, nearly smooth species has so far been reported only t'loni tlic 

 Pliocene of San Diego, where it is quite conininn. 



P/iocene.— San Diego (Henipliill; Stearns; Arnold). 



279. Opalia borealis Gould. 



Sea/aria 6area/is GLD.,W\\kcii' Exped., \\>\. XII, 1S52, p. 207. Tkvon, Man. Concli., \V)I. IX, 



p. 76, PI. XVI, fig. 89, 1SS7. 

 Ofia/ia dorea/is Gld., Ci'R.. Brit. Assn. Rept, 1863, p. 660. Cooper, 7ih Ann. Rept. Cal. St. 



Min., 1888, p. 255. Keep, West Coast Shells, p. 49, fig. 30, 1892. 

 Scaia (Opalia) borealis Cpr., Williamson, Proc. U. S. Nat. Mus., Vol. XV, 189J, p. 210. 



Shell small, turreted, thick; apex generally decollated; whorls sevLii, oiih- slightly conve.x; 

 varices eight, rounded, thick, prominent, and forming radiating ridges from the apex; suture im- 

 pressed, distinct; body-whorl squarely angulated at base, with keel on angle; base flat, smooth; 

 aperture subovate; outer lip thin, effuse; inner lip only slightly incrusted. 



Dimensions. — Long. 15 mm.; lat, 6 mm.; defl. 22 degrees. 



The specimens described were identified by Dr. Dall. 



Rare in upper San Pedro series of San Pedro; two specimens. 



Licing. — Karatschatka; Straits of Fuca to San Diego (Cooper). 



Pleistocene. — Santa Barbara (Cooper): San Pedro (AriKjld). 



