Queer Friendships 



entertaining. He takes every precaution that his new 

 dwelling is fit for habitation and, having satisfied himself 

 on that score, he transfers his ungainly body from one 

 shell to another with a celerity which is astonishing. 

 When the new home proves unsuitable, back he dashes to 

 his late abode, which, by the way, never leaves his grasp 

 till he is satisfied that he will want it no longer. 



Some hermit crabs, however, more fortunate than their 

 fellows, are saved all worries of house moving and that by 

 the good offices of a friendly sponge. The young sponge 

 takes up its abode on the whelk or other shell which is 

 serving as a shelter for a hermit crab. Rapid growth 

 takes place and it is not long before the shell, with the 

 exception of the mouth, is completely enveloped by the 

 sponge. 



Now it is a remarkable fact that, whatever the size 

 attained by the sponge, and it is often considerable, the 

 opening of the shell is never closed, but a tubular passage is 

 always in front of it. It frequently happens that sponges 

 and their kind, when they settle on a shell in this manner, 

 eat away its substance, or at least cause it to become so 

 rotten that the water soon completes the work of destruc- 

 tion ; the sponge we are describing never damages the 

 hermit crab's shell. 



As may be imagined, there comes a day when the crab 

 is too large for his home, so he simply walks a little way \ 

 down the tube of sponge which has been built up 

 before his door and, by so doing, avoids the trials and 

 dangers of changing his shell ; for, being a soft-bodied 

 creature, the danger when uncovered by a shell, as he is 

 for a moment or two when he is engaged in moving, is 

 very great. Enemies await this change and catch him 

 moving if they are able. The sponge then, apparently a 

 hindrance to the movements of the crab, in reality pro- 

 vides him with a house which grows continuously ; a house, 

 moreover, which affords him ample protection. The con- 

 tinual transport from place to place which the sponge 



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