284 WEST COAST SHELLS 



ted, rather thin, faintly indented and granulated; 

 ash-yellow with a chestnut band, lip white, reflexed 

 at the base. Whorls six, spire moderately elevated, 

 diameter one inch. It lives near the coast of central 

 California. 



Var. ramentosa^ Gld. The surface of the shell is 

 cut up into innumerable checks, which are shown by 

 a lens to consist of little oblong grains, arranged 

 parallel to the lines of growth. The epidermis of 

 the young ones is studded with little bristles. 

 Diameter about three-fourths of an inch. This 

 form is found in Alameda Co., Cal., and in adjacent 

 regions. 



Var. diahloensis^ J. G. Cooper, has a flattened 

 shell, umbilicated and thin, with regular mallea-. 

 tions arranged in revolving series, like dents caused 

 by the blows of a small hammer. Diameter rather 

 less than an inch. From the Coast Mountains of 

 central California, being named from its occurrence 

 near Mt. Diablo. 



Var. contracostae^ Pils., is smaller than the last 

 variety, yellowish straw-colored, only slightly mal- 

 leated, outer lip thickened. From Byron Hot 

 Springs, Contra Costa Co., Cal. 



Yjpiphragmophora ayresiana^ Newc, Ayer's 

 Snail, is a species from the islands of Santa Rosa, 

 San Miguel and Santa Cruz. The shell is quite 

 strong, six-whorled, and it has a considerably ele- 

 vated spire and a distinct umbilicus. Microscopic 

 striae may be traced upon the shell. It is of a 

 brown or chestnut color, and it is usually girdled 



