106 PALAEONTOLOGY OF CALIFORNIA. 



length; merging into the lip anteriorly. Umbilicus minute, 

 barely visible. Surface marked by somewhat irregular lines of 

 growth. There is no opercular scar on the columellar callus. 

 Length, .75 inch. 



Locality: Cottonwood Creek, north fork (Division A.). 



L. Shumardiana, n. s. 



PI. 19, Fig. 61. 



Subglobose; spire not prominent ; whorls four to four and a 

 half, convex ; suture impressed. Surface marked by pretty dis- 

 tinct and somewhat irregular lines of growth, most strongly 

 marked in the larger specimens. Aperture ovate, broadly 

 rounded in front, subacute posteriorly. Columellar callus dis- 

 tinct, somewhat thickened, abruptly contracted just above the 

 umbilicus, and then continued, much narrower, to the anterior 

 end of the mouth. Umbilicus small, but distinctly perforate. 

 ~No opercular impression on the columella. 



Figure, natural size. 



This species is closely allied to L.coneinna, M. and H., but is considerably larger 

 and more oblique; the callus is heavier and more suddenly truncated at the um- 

 bilicus; it wants the opercular impression on the callus found in that species, and 

 has one more volution. The latter character might be accounted for, however, 

 by the difference in size. 



Locality: Hills, southwest of Martinez (Division B.) ; abundant. Named in 

 honor of Dr. B. F. Shumard, of St. Louis, Mo. 



L. Hornii, 11. s. 



PI. 29, Fig. 217. 



Shell subglobose ; spire small, acute, not prominent ; whorls 

 five, almost entirely enveloped, except the newer portions of the 

 penultimate volution. Aperture semilunar, rounded below; 

 outer lip acute, nearly straight; columellar lip with a moderately 

 large callus, thickened above, smaller and flat below, continuing 

 as a thickened lip almost to the anterior end of the mouth. Um- 



