108 CALIKOUNIA AiADKMY Ol' SCIENCES. 



115. Psammobia (Psammobia) edentula (lahli. 



SiteqHitria eJiiiliila IIaiih, I'.il. Cal., \\>\. II, p. 5;,, I'l. .W, lii;. 11, i.S'nj. t'odi'i u, 71I1 Ann. 



Rtpt. Cal. St. Mill., i,S8,S. p. 264. 

 Psammobia fJenlula Gaisb, Dali., 'rr.ins. W'agmr Inst. vSci., \'ul. Ill, l';irl 5, lyoo, p. 976. 



Slioll large, floiig.itcil, siit)clllptical, llalteiiecl, thin; beaks minute, i)Osterior to micklle; 

 surface marked by distinct lines ol' growth most prominent near the margin; cardinal margins 

 straight, sloping gently towartl the ends; anterior end convexly and very obliquely sublruncate 

 above, proiluced and rounded below; posterior end broadly and regularly rounded, a little less 

 prominent below than above the miiiille; basal margin nearly sir.iiglit; liganiental are.i long, pro- 

 jecting prominently beyond the cardinal line for nearly iialf ihi liiigih of tlie anterior jjorlion of the 

 shell: ]>rojectcd area with large groove on outside, flat on insitle; two prominent cardinal teith, 

 anterior less prominent and obli(|ue; anterior nuiscleinij)ression large, suijcircular; posterior smaller, 

 subelliptical; pallial sinus deep and wide. 



Dimensions. — Long. 1.^5 mm.; alt. 69 mm.; diam. 13 mm. 



Tliis fine sliell was originally described liy (Jabb ffoin a specimen obtained in 

 tlie I'iiocenc of San Fernando. On account of tbe matrix in wliicb bis specimen 

 was imi)eddcd, tbe binge area and interior were only partly accessible, bcnce it was 

 deemed expedient to more fidly describe tbe interior of tbe sbell. Dr. Dall pro- 

 nounced tbe sbell described above a member of tbe genus Paaininobla. Tbe cardinal 

 teetb, bowever, are ratber large for one of tiiis genns. 



Rare in tbe upper >San Pedro series of >San Pedro; tbree good specimens 

 obtained. 



Living. — ? 



Pleistocene. — San Pedro (Arnold). 



Pliocene. — San Fernando (Cooper). 



Goiui.s Sanguinolaria Lmimrck. 

 Section Xiitt(dlin D<ill. 



Sliell large, suborhicular, inequivalve, more or less twisted, the right valve slightly flatter; the 

 posterior cardinal in the left valve obsolete; tiie p.illial sinus narrow in front and somewhat detached 

 from the p dlial line. 



Type, Sanguinolaria nnttalii Conrad. 



116. Sanguinolaria (Nuttallia) nuttalli Conrad. 



Sanguinolaria nntlalli Con., Jour. Phil. Acad. .Sci. , Vol. VII, 1837, p. 230, PI. XVII, fig. 6. 

 Carpenter, Brit. Assn. Kept., 1863, p. 638. Keep, West Coast Shells, p. igS, 

 fig. 170, 1892. Williamson, Proc. U. S. Nat. Mus. , Vol. XV, 1892, p. 185. Dall, 

 Trans. Wagner Inst. Sci., \\i\. Ill, Part 5, 1900, p. 979. 



Shell large, subovate, thin; right valve venlricose, left compressed; unibones small, distant 

 from anterior margin, slightly prominent, acute; surface smooth, except for fine incremental lines; 

 anterior dorsal margin sloping concavely; posterior end evenly rounded from beaks; anterior end 

 more sharply rounded and much more produced; ventral margin evenly curved; cardinal teeth 

 prominent, fragile; ligamental area prominently projecting beyond cardinal line. 



Dimensions. — Long. So mm.; alt. 59 mm.; diani. 23 mm. 



