80 THE STORY OF ANIMAL LIFE 



between tides. In placed where the rocks of the 

 coast are very steep, a belt of white, several feet 

 or yards deep, may often be seen above low- 



FlG. 15. Shells of a Barnacle, Balanus /lameri, found in European 

 and North American Seas, natural size. 



water mark. This white zone, when examined 

 more nearly, is found to consist of barnacles, so 

 crowded together that they obscure the natural 

 colour of the rock. The Common Barnacle is 

 one of the smaller species of the genus: in 

 warmer seas barnacles attain to a much greater 

 size (Figs. 14 and 15). 



The higher Crustacea, Malacostraca, include 

 the familiar Crabs and Lobsters, Decapoda. The 

 lobsters receive the name of Macrura or Big-tails; 

 associated with them are the Shrimps and the 

 Hermit-Crabs (Fig. 16). The latter are therefore 

 not crabs at all, but somewhat divergent lobsters. 

 Their tails are soft, and they thus require pro- 



