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THE SEA CRABS. 



THE HERMIT CRAB. 



Sand Crabs, which burrow in the sand, and lie perdu at 

 the bottom of their excavations ; and Calling Crabs, carry- 

 ing aloft the enormous claw in whose beckoning gesture 

 has originated their popular name. The aquatic crabs 

 and shore crabs in their general organization resemble 

 the crustaceans already described, and undergo the same 

 process of " moulting," or exuviation. They are remark- 

 able for their complex masticatory apparatus. The 

 mouth is provided with fully eight pieces or pairs of 

 jaws, which pass the food through an exceedingly short 

 gullet into a membraneous stomach of considerable size. 

 This stomach contains certain cartilaginous appendages, 

 five in number, to which strong, grinding teeth are at- 



