186 



WEST COAST SHELLS 



Having studied small 

 shells for some time we 

 turn now to a large one, 

 shown in Figure 176, 

 named Scaphella stearnsil^ 

 Dall, Stearns's Volute. This 

 great shell, which is nearly 

 six inches long, comes from 

 northern Alaska. The inner 

 layer is purplish, while the 

 outer, which resembles 

 porcelain, is bluish white. 

 Note the distinct folds on 

 the columella. 



Scaphella arnlieimi^ Riv- 

 ers, Arnheim's Volute, 

 dredged from Monterey 

 Bay a number of years ago, 

 resembles the last species, 

 but is only half the size. 

 The color is yellowish, and 

 the folds on the columella are four in number. It 

 is to be hoped that more specimens of this line species 

 may yet be obtained from beautiful Monterey Bay. 



We are now to consider the 'Pyramldellidae^ a 

 family of small mollusks, having turreted shells with 

 a plicate axis. The three principal genera are Pyra- 

 midella^ l^urhonilla and Odostomia. Most ot the 

 shells are too small to attract much notice, except 

 from experts, and a careful examination of them 

 must be made with the aid of a microscope if they are 



Fig. 176. xS (*) 



