The Shell-bearing Sea Slugs 



A. Californica, Coop., rarely cast ashore by storms on the 

 west coast, reaches fifteen inches in length. 



THE UMBRELLA SHELLS 



Family Umbrellid.^ 

 Genus UMBRELLA, Lam. 



Shell flattened, limpet-like, thin, calcareous; foot large, 

 thick, notched; snout large, retractile, with lobed veil; tentacles 

 ear-like. 



Six species of marine mollusks, scarcely protected by their 

 oblong, lid-like shells, under which the branchiae and other 

 delicate organs lie. 



U. Indica, Lam., is as large as the palm of the hand, white 

 and polished within. Outside it is rayed from the central apex 

 with obscure brown bands. 



Habitat. — East Indies. 



The Mediterranean Umbrella (U. Mediterranea, Lam.) 

 has its rows of short plumed gills scarcely under the edges of its 

 flat shell, an absurdly small Chinese umbrella, compared with 

 the inordinate development of the foot. The disk of leather 

 that covers the palm, bears about the same relation to the 

 padded portion of a boxing glcve. Length, 3 inches. 



Habitat. — Mediterranean. 



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