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GENERAL ZOOLOGY 



Hermit-crabs live in great abundance along gravelly beaches, 

 where they are useful scavengers of dead animals in the water. 

 In spite of the heavy houses which they carry, they move 

 about with surprising facility. As suggested by one observer, 

 they are wary, cunning, belligerent, and cowardly, making 

 great pretense of fighting, but on the first show of force by 

 an opponent they withdraw into their shells. 



A small shore species more frequently seen never becomes 

 as large as Eupagurus pollicaris, which is a deep-water species. 

 All the species, however, when the individuals are young, 



FIG. 71. Hermit-Crab and Blue Crab, x 



choose small shells ; as they grow older and larger after each 

 molt, the unused space in the shell becomes less and less. 

 Naturalists have observed the action of hermit-crabs that have 

 become too large for the shell. The animal searches about for 

 a suitable larger shell, and when it finds one withdraws the 

 body from the old shell and extends it into the new. 



The spider-crab (Libin'ia emargina'ta, frontispiece) stalks 

 slowly over the sea-bottom in shallow and deep water where 

 rocks and fixed plants and animals abound. It can neither 

 run nor swim, an inference which might be drawn from the 



