120 PALAEONTOLOGY OF CALIFORNIA. 



prominent on the upper than on the lower side. Surface smooth. 

 Aperture simple, circular. 



Diameter, .22 inch ; width of body whorl, .05 inch. 



Locality : Texas Flat, Placer County (Division A.). Collection of the Academy 

 of Natural Sciences of California. 



This shell, named in honor of Mr. Lea, President of the Philadelphia Academy 

 of Natural Sciences, is almost a perfect miniature of Ammonites Batesii. The 

 margin differs from O. rotclla, Lea, of the Alabama Eocene, in being round, 

 instead of bicarinate ; and it can be distinguished from D. foliacea, Philippi, (re- 

 cent) by the whorls being circular, instead of flattened. 



STRAPAROLLUS, Montf. 



(Euomphalus, Sow.) 

 S. paucivolvus, n. s. 



PL 20, Fig. 76. 



Shell flattened; spire low; whorls few, number unknown, 

 increasing rapidly in size, rounded, subovate in section, most con- 

 vex below ; suture impressed. Umbilicus rather wide. Surface 

 smooth, or marked only by lines of growth. 



Diameter, .26 inch; width of aperture, .10 inch; height of 

 aperture, .09 inch. 



Locality: With the preceding. 



S. LENS, 11. S. 

 PI. 20, Fig. 77, a, b, c, and d. 



Shell minute, lenticular; spire low, slightly convex; whorls 

 seven, rounded above, subangular on the margin, sloping con- 

 vexly inwards to the margin of the umbilicus. Umbilicus be- 

 tween a third and a quarter of the diameter. Mouth narrow, 

 subquadrate, and sloping inwards. Surface smooth or striate by 

 delicate lines of growth. 



Diameter, .3 inch; height, about .14 inch; width of mouth, 

 .04 inch. 



