CRETACEOUS FOSSILS. 161 



NEVERITA, Risso. 



K". GLOBOSA, n. 8. 

 PI. 27, Fig. 39. 



Shell subglobose, spire low, acute ; whorls rounded, five and 

 a half, rapidly increasing in size, the last sloping above, and 

 slightly flattened on the side ; umbilicus small but well marked. 

 Aperture suboval, narrower above than below ; outer lip simple, 

 inner lip with a heavy callus, prominent above, slightly flattened 

 on the inner face, the portion over the umbilicus flat, rather thin, 

 and sometimes bearing a faint transverse groove. 



Length, .75 inch ; width, .72 inch ; length of aperture, .68 inch ; width of aper- 

 ture, .32 inch. 



From Neverita secta, its nearest ally, this shell can be distinguished by its mucb 

 more globose form, the upper part of the whorl being round instead of sloping 

 almost regularly from the apex ; it is not so wide at the base ; the callus is very 

 large posteriorly, instead of being thin and narrow as in secta, and the portion 

 over the umbilicus is small, rounded and flat, instead of being, as in secta, large, 

 convex, and triangular. 



From the Tejon Group, ten miles west of Griswold's, on the road from San Juan 

 to New Idria, and southeast of the "Sheep "Well." 



AMPULLINA. 



A. STRIATA, n. S. 

 PI. 27, Fig. 40. 



Shell small, compact, subglobose, whorls five, rounded, suture 

 deep, whorls in some cases rounded, subtruncated above, adjoin- 

 ing the suture, in other specimens regularly rounded. Surface 

 ornamented by numerous, minute, revolving, impressed lines, 

 more or less interrupted by the lines of growth. Aperture subo- 

 vate, widest in advance ; outer lip thin, simple ; inner lip simple, 

 terminated anteriorly by a narrow, flattened margin commencing 

 in the umbilical region ; umbilicus closed or minutely perforated. 

 pal. vol. ir. — 22 



