316 CORAL AND ATOLLS 



large numbers maybe seen at certain times marching in armies 

 along the lagoon shores, some wholly in the water and some 

 in the wash ; and they are there doubtless for the purpose of 

 depositing their ova. 



Its burrows, too, are always made down through the loose 

 debris to the water-level, so that the crab when residing even 

 in the centre of an island is always able to get into the water 

 at the bottom of its burrow when it wishes to moisten its 

 gills. 



The other land crabs of the order Brachyura, such as the 

 handsome red Gecarcoiclea lalandei, and the members of the 

 genus Geograpsus, live for the most part beneath the loose coral 

 boulders and the roots of trees, and Gecarcoiclea lalandei seems 

 to have cut itself off from the water very completely at all 

 times of the year save that in which it goes to the beach for 

 the purpose of depositing its ova. 



It is the members of the order Anomura that have most 

 successfully become land animals, and the great " robber crab " 

 {Birgus latro), whose native name is Vclung darat, is the most 

 completely terrestrial of them all. 



The " robber crab " is becoming rare in the Cocos atoll, 

 and I only succeeded in getting possession of five in the fifteen 

 months I lived in Pulu Tikus : but in Keeling atoUon it still 

 lives in abundance. It is a very remarkable creature in every 

 way, and no notion of its uncanny cleverness would be 

 imagined from a mere inspection of the animal ; but the 

 Birgus is one of the cleverest animals living. Its strength is 

 quite incredible. It can nip through wire netting as easily as 

 can a man with cutting pliers. It can tear up tin with ease, 

 and break with its great pinchers the wooden bars of a cage 

 that would serve to imprison a large wild animal. Added to 

 this, it possesses an extraordinary quickness of movement, so 

 that the sudden and well-aimed grabs that it will make are 

 far more reminiscent of the actions of a great spider than of a 

 crab. 



So far as I observed, in regard to those that I kept in 

 captivity, the Birgus is far more fond of dead rats or meat 



