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its dwelling that it is torn if we attempt to drag it out. 

 The shell protects the soft body of the crab, and is generally 

 so big , that the crab can completely conceal itself when in 

 danger. As the animal grows, it must naturally remove to a 

 larger shell , which operation is effected with great skill and 

 caution. Having found a shell to suit him, the crab first ca- 

 refully examines it all over, poking his claws into it to make 

 sure that there is nothing suspicious at the bottomland, if all 

 is right, he at last carefully prepares to effect the removal. He 

 gets hold of the shell with his claws , places it upright with 

 the opening turned towards him , and then , with one quick 

 movement, forsakes his old shell and slips into the new one, 

 as if he very well guessed what a tit-bit his soft and juicy body 

 would be for a hungry fish. 



Bnt what business have the sea-anemones that are regularly 

 settled upon all the shells occupied by hermit-crabs, often from 

 three to six in number , and yet nowhere in any bodily con- 

 nection with the crab? The fact is, that the hermit-crab and 

 the sea-anemones have formed an alliance. The latter protects 

 the crab from its enemies by means of the poisonous nettle- 

 cells of its tentacles, while the vagabond habits of the crab 

 give the anemone a greater chance of finding nourishment, for 

 the latter is being constantly brought into contact with all kinds 

 of animal life, or else catches the bits that fall during the crabs 

 own meal. This fact is proved by the beautiful purple -spotted 

 Anemone Adamsia palliata, which always fastens on the shells 

 inhabited by the Eupagurus Prideauxii and is usually so pla- 

 ced that the orifice of its mouth is turned downwards. But the 

 most wonderful thing is that the crab knows its friends, and 

 not only tries to put anemones on a shell that is without them, 

 but actually, when it changes its abode, takes its companions 

 along with it ! 



An experiment , in which all the sea anemones were 'taken 

 away from the shell of a hermit-crab, and replaced before the 

 eyes of the experimenter by the crab pressing them with his 

 claws out the shell until they had again fastened , places the 

 above fact beyond all doubt, and proves the alliance to be one 

 of the most remarkable known among the lower animals. 



The life of the hermit-crabs in the Aquarium offers a picture 

 rich in varied and amusing scenes. The droll fights of the little 

 troop, the impudent seizures on the one part and the resolute 

 defence on the other during the common meal , involuntarily 

 excite the laughter of the spectator who is often greatly surprised 



