216 PALAEONTOLOGY OF CALIFORNIA. 



BARBATIA, Gray. 

 B. MORSEI, n. s. 



PL 32, Fig. 286. 



SHELL small, thin, subcompressed, oblique, broadest posteri 

 orly ; beaks small, approximate, anterior ; area long and very 

 narrow, shorter than the shell; anterior end short and broad; 

 posterior end oblique above, rounded below; base sinuous, 

 slightly gaping. Surface depressed in the middle and towards 

 the ends, ornamented by numerous fine radiating ribs, alternat 

 ing pretty regularly in size in the middle of the shell. Hinge 

 slender, composed of numerous small, oblique teeth. 



Figure, natural size. 



Locality: San Diego ; collected by Mr. Morse. 



YOLDIA, Moller. 



Y. NASUTA, n. 8. 

 PL 32, Fig. 287. 



SHELL thin, convex, elongate; beaks subcentral, a little pos 

 terior; cardinal margin concave in advance, sinking convexly 

 behind ; anterior end produced, most prominent above. Hinge 

 composed of uniform teeth, largest in advance of the beaks. 

 Surface polished. 



Figure, natural size. 



Locality: A single specimen in the collection of the California Academy of 

 Natural Sciences, labelled "Los Angeles," and associated with Cretaceous fos 

 sils. This shell may be Cretaceous, or possibly Tertiary. The discovery of better 

 authenticated specimens will be necessary to determine its true age. 



