How Animals Work. 



great Birgos, or Robber Crab, which lives in a den 

 which it digs for itself in the earth, and is found on 

 islands in the Indo-Pacific seas. To talk of a great 

 crab which lives on land, climbs palm trees, and breaks 

 open cocoa-nuts, sounds as if one were verging strongly 

 towards the region of romance ; yet Nature is full of 

 such surprises, outrivalling the strangest dreams of the 

 imagination. The Birgos is such a crab, although its 

 ability to climb far up a tree seems rather doubtful ; 

 and of its curious habits Darwin, in his account of his 

 voyage round the world in the Beagle, gives the follow- 

 ing interesting description : "I have before alluded to 

 a crab which lives on the cocoa-nut ; it is very common 

 on all parts of the dry land, and grows to a monstrous 

 size ; it is closely allied or identical with the Birgos latro. 

 The front pair of legs terminate in very strong and heavy 

 pincers, and the last pair are fitted with others weaker 

 and much narrower. It would at first be thought 

 quite impossible for a crab to open a strong cocoa- 

 nut covered with the husk ; but Mr. Liesk assures 

 me that he has repeatedly seen this effected. The 

 crab begins by tearing the husk, fibre by fibre, and 

 always from that end under which the three eye-holes 

 are situated ; when this is completed, the crab com- 

 mences hammering with its heavy claws on one of the 

 eye-holes till an opening is made. Then turning round 

 its body, by the aid of its posterior and narrow pair of 

 pincers, it extracts the white albuminous substance. 

 I think this is as curious a case of instinct as ever I 

 heard of, and likewise of adaptation in structure between 

 two objects apparently so remote from each other in 

 the scheme of nature as a crab and a cocoa-nut tree. 



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