PLANT-EATING CRUSTACEA 



221 



\i.e. the equivalents of a lobster's great claws] terminate in 

 very strong and powerful pincers, and the last pair but one 

 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 



Fig. 448. Robber- or Cocoa-nut-Crab (Birgus latro] 



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 commences 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/' Forbes (in A Naturalist's Wanderings in the Eastern 

 Archipelago] gives further details, stating that the proper eye- 

 hole (only one of the three is soft) is pierced by means of the 

 pointed end of one of the walking-legs, the orifice, when suffi- 

 ciently enlarged, being still further widened by the great claws. 



