258 CALIFORNIA ACADKMY OF SCIliNCES. 



Distiiiguishal)le by l)roiul ami depressed form, bioiid, rounded ridges, and 

 prominence of the spiral lines and incremental linihe. Speeinieii identified by 

 Dr. Dall. 



Rare in upper San I'edro series at Han I'edro. The t-peeinien figured is 

 from the upper San Pedro series at San Pedro, and is now iu the United States 

 National Museum. 



Living. — Straits of Magellan (Tryon). 



Pleistocene. — Sau Pedro (Arnold). 



265. Ocinebra lurida Miild., var. cerritensis, vur. nov. 

 Plate V, Fig. 5. 



Shell small, broadly fusiform, heavy; spire elevated, subacute; whorls four, convex, enlarj>;ing 

 rapidly from the first whorl; body-whorl ventricose; whorls crossed by about nine prominent, rather 

 narrow, rounded ribs, which extend to end of columella; interspaces ornamented with strong, raised, 

 spiral lines; suture impressed, not very distinct; aperture subelliptical; outer lip thickened, with a 

 row of about six prominent denticles; inner lip smooth, incrusted; columella not much widened, 

 abruptly truncated at end; umbilicus subperforate; canal short, straight, narrow. 



Dimeiisiotis. — Long. 17 mm.; lat. 10 mm.; body-whorl 14.5 mm.; aperture 11 mm.; canal 

 3 mm.; defl. 60 degrees. 



Distinguishable from others of its genii:^ by large body-whorl, depressed 

 appearance, small size and heavy shell. Pronounced a new variety by Dr. Dall. 



Rare in upper San Pedro series of the San Pedro region; first found at Los 

 Cerritos; type from Crawfish George's; also found in the lower San Pedro series at 

 Deadman Island and San Pedro. The specimen figured is the type, which is now in 

 the United States National Museum. 



Pleistocene. — Sau Pedro (Arnold). 



266. Ocinebra lurida M'uhL, var. munda Car])enter. 



Ocinebra lurida \a.r. munda Ci'K., Brit. Assn. Rept., 1863, p. 663. D.\ll, Proc. U. S. Nat. Mus. , 

 Vol. XV, 1892, p. 215, PI. XX, fig. 3. 



Shell small, fusiform, thick, solid; spire elevated, apex acute; whorls five or six, evenly 

 convex; sculpture consists of rather low, rounded, transverse ridges (of which there are about twelve 

 on the penultimate whorl) and equal, equidistant, rounded, raised, spiral lines (of which there are 

 six on the penultimate whorl); suture quite deeply impressed; aperture elliptical; outer lip thick- 

 ened with row of denticles interiorly; inner lip and columella smooth; canal short, narrow, 

 generally covered. 



Dimensions. — Long. 14 mm.; lat. 6.5 mm.; body-whorl 10 mm.; aperture, including canal, 

 7.5 mm.; canal 2.5 mm. 



Distinguishable from others of the genus by its low, rounded, transverse ribs, 

 which are of the same size and prominence from suture to suture, regular s^nral lines 



