286 CALIFORNIA ACADEMY OF SCIENCES. 



306. Tritonium gibbosus Broderip. 



Triton gibbosus Brod., Proc. Zool. Soc, 1833, p. 7, P). VII. Kuster, Conch. Cab., p. 69, fig. 7. 

 Tryon, Man. Conch., Vol. Ill, p. 23, PI. XII, fig. 103, 1881. Cooper, Bull. No. 4, 

 Cal. St. Min. Bureau, Part III, 1894, p. 32. 



Shell small, subfusiform; whorls five, subtriangular, strongly angulated, giving tabular 

 ap[)earance to the upper part of whorls; prominent rounded, nodose varices at about every two- 

 thirds of a revolution, with two or three nodes on angle of whorl in intervening spaces; suture reaching 

 nearly to columella, giving a staircase appearance to the spire; surface ornamented with small, 

 revolving ridges made rugose by incremental lines; aperture subcircular; outer lip slightly corru- 

 gated internally; inner lip smooth, incrusted; canal long, narrow, curved slightly back; umbilicus 

 subperforate. 



Dimensions. — Long. 41 mm.; lat. 22 mm.; body-whorl 28 mm.; aperture 10 mm.; canal 

 II mm.; defl. 56 degrees. 



A unique shell, the only one of its genus so far recorded as occuring fossil in 

 California. 



Rare in upper San Pedro series of San Pedro; one specimen found. Dr. 

 Dall also reports one found in the bay at this place, which he thinks is a fossil that 

 had been weathered out of the Pleistocene beds. 



Living. — West tropical America; Panama (Cooper). 



Pleistocene. — San Pedro (Dall; Arnold). 



Subgenus Priene H. d- A. Adams. 



Shell ventricose, thin, cancellated or plicated ; canal short ; operculum with apical 

 initial point. 



307. Tritonium (Priene) oregonensis Redfidd. 



Plate VI, Fig. 1. 



Triton oregonetrse Kedf., Ann. N. Y. Lye, Vol. IV, 1846, p. 165, PI. XI, figs. 2a, 2b. Gld., 



Wilkes' Expl. Exped., Vol. XII, p. 241, 1852. 

 Fusus oregonensis Redf., Reeve, Icon. Conch., No. 61, figs. 6ia-d, 1848. 

 Triton (Priene) oregonensis Redf., Cpr., Brit. Assn. Rept., 1863, p. 66r. 

 Tritonium (Priene) oregonensis Redf., Gabb, Pal. Cal. Vol. II, p. 73, 1869. 

 Tritonium oregone7ise Redf., Dall, Proc. U. S. Nat. Mus., Vol. IX, 1887, p. 212. 

 Priene oregonensis Redf., Cooper, 7th Ann. Rept. Cal. St. Min., 1888, p. 261. Keep, West Coast 



Shells, p. 44, 1892. 

 Priene cancellatus Lam. {fide Tryon, Man. Conch., Vol. Ill, p. 34, PI. XVI, figs. 164-167; 

 PI. XVII, figs. 170-172, 1881) (pars). 



Shell large, fusiform; spire elevated; apex blunt; whorls eight to ten, convex; nuclear 

 whorls smooth, except for obsolete spiral striations; cancellated sculpture of nearly equally promi- 

 nent spiral and transverse rounded ridges; suture deeply impressed; discontinuous rounded varices 

 at every half to two-thirds revolution on upper whorls; aperture subovate; outer lip not thickened, 

 slightly effuse on adult shells; canal long, narrow, recurved; inner lip incrusted; columella slightly 

 twisted; umbilicus obsolete. 



Dimensions. — Long. 103 mm.; lat. 48.5 mm.; body- whorl 71 mm.; aperture 31 mm.; canal 

 21 mm.; defl. 47 degrees. 



