CRABS. 241 



The Hermit or Soldier Crab. — (Plate XI.) 



The common species, Pagurus Bernhardus, is the one 

 usually seen in tanks, where it presents a most interesting 

 object. Crawling clumsily about with a shell not its own 

 upon its back, it seems as if it were not in its natural con- 

 dition, and yet that is the condition in which it is always, or 

 almost always, found: and if by any accident the hermit is de- 

 prived of his portable cell, he is about as uncomfortable as 

 a fish out of water till he finds another, and if unsuccessful 

 dies. There seems to be something so strange in this habit 

 of choosing the covering of another animal for a dwelling, and 

 the parts of the body which are protected by it appear so 

 contorted, ill-formed, and irregular, that I am tempted al- 

 most to refer it to some accident of very frequent occurrence. 

 Might it not be, that the Zoe or Tadpole form of some 

 common species, produced where empty shells of difi'erent 

 sorts and sizes lie strewn plentifully among pebbles and 

 sand, falling into some of the hollows, and becoming con- 

 fined, or liking the condition, remained in it through sub- 

 sequent changes, and tliat thus what is first an accident 

 becomes a habit ? Even if this were the case, it would re- 

 quire a course of observation and many experiments to esta- 



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