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: Cotton wood 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. coticinna, 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 MartiHez (Division B.); abundant. Named in 

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



L. HORNII, n. 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- 



