430 



THE OCEAN WORLD. 



larger as well as more numerous and much richer in colour in 

 equatorial seas, and especially in the southern hemisphere, than in 

 European seas. They attain, in fact, their maximum of develop- 



Fig. 211. — Patella caerulea (Lamarck}. 



Fig. 212. — Patella umbelia (Gmel.) 



ment there ; for in the Straits of Magellan species are found as large 

 as a slop-basin, which the natives use for culinary purposes. 



The common limpet is thick, solid, oval, and nearly circular, 

 generally conical, and covered with a great number of very fine 



Fig. 213. — Patella granatina (Linnaeus). 



Fig. 214. — Patella barbata (Lamarck). 



Stripes. Its colour is of a greenish grey, uniform above, and of a 

 greenish yellow inside. It is abundant in the Channel and on 

 Atlantic coasts. 



The blue limpet, Patella cccruka (Fig. 211), from St. Helena, 

 has an oval shell, broadest benind, moderately thick, depressed, 



