CHAPTER II 



Life of the Snails 



The private lives of the snails, or gastropods as they are more correctly 

 called, are almost as varied as the different kinds of seashells that are found 

 along our beaches. More than half of the 80,000 species of existing snails live 

 under marine conditions, the remainder being air-breathing land species or 

 inhabitants of fresh water. In their evolutionary struggle for existence, they 

 have shown an amazing diversity in adapting themselves to nearly every con- 

 dition found in the sea. There are snails that creep, jump, swim, burrow, 

 some that are permanently anchored to rocks and a few that live inside other 

 marine creatures. In a few cases, as in some conchs and top shells (Troclms), 

 the snail may play host to small fish and tiny crabs. 



Gastropods have experimented in all manner of forms, colors and sizes. 

 In size they vary from the two-foot-long Horse Conch of Florida {Pleuro- 

 ploca gigantea) to the microscopic Vitrinellas that scarcely exceed the size 

 of a grain of sugar. Some species display unusual ornamentation and, as in 

 the Murex shells, produce long, delicate spines. There are few objects in 

 nature that can vie in beauty with the glistening sheen found in the shells of 

 the ohves and cowries. On the other hand, the beautiful sea slugs or nudi- 

 branchs may entirely lack a shell. The Carrier Shell, Xenophora, has ac- 

 quired the strange habit of collecting shells, bits of coral and other hard 

 objects, and cementing them to its own shell. 



WHERE THEY LIVE 



From the high levels of the coastal cliffs to the canyons of the ocean's 

 bottom, a thousand kinds of habitats have been adopted by marine gastro- 



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