290 



WEST COAST SHELLS 



Los Angeles, in the yard of Dr. Stearns. It has 

 been reported from Oakhmd and many other locali- 

 ties in California, also from Utah and adjacent 

 states. 



Vallonia costata^ Mull, the Ribbed Vallonia, is 

 another very small species, the shell being only 2.5 

 mm. in diameter. Horn-colored, nearh- flat, iim- 

 bilicated, with regularly set membranous ribs, and 

 fine stride between them. It has about the same 

 range as the last species. 



A genus of medium sized mollusks living chiefly 

 in New Mexico was named by Professor Pilsbry 

 Ashmunella^ in honor of the late Rev. E. H. Ash- 

 mun, of happy memory, who united with his clerical 

 duties the enthusiasm of the naturalist. The shells 

 in general are about half an inch across, horn-col- 

 ored, with Ave or six whorls, a small but distinct 

 umbilicus, and a white, reflexed outer lip. Some of 

 them were formerly referred to the genus Polygyra. 

 In this book I shall not attempt to name them all, 

 but will mention a few, specimens of most of which 



were sent me by Mr. Ashmun him- 

 self. 



AshmuneUa rhyssa^ Dall, the 

 Wrinkled Snail, is shown in Fig- 

 ure 279. The shell consists of six 

 rounded, yellowish whorls, which 

 are crossed by very numerous 

 wrinkles. The reflected peristome 

 is white, and immediately behind 

 it the shell is considerably con- 

 I'ig. 279. X -2 (*) stricted. It was collected in the 



