THE GREAT ROBBER-CRAB 83 



The king of these land-crabs is Birgus latro, a true 

 hermit-crab, but of a size too gigantic to fit into any 

 empty mollusk shell, after the usual habit of its tribe. 

 Being independent of a shell, its **tail," or abdomen, 

 instead of being soft and spirally-twisted, as it is in 

 most hermit-crabs, is straight, and is clad dorsally 

 with hard plates of its own. Being practically an air- 

 breather, it also differs from most other hermit-crabs, 

 which are water - breathers, in the nature of its 

 breathing-organs ; for although, like the majority of 

 hermits, it has fourteen pairs of gills, these are of 

 very small size, and breathing is chiefly effected by 

 spongy, vascular, arborescent growths, or warts, of 

 the lining membrane of the gill-chamber. It is also 

 very massively built, but except in these few parti- 

 culars, it does not essentially differ from the common 

 soldier-crab of British shores. Its proportions may 

 be imagined from the statement that a good - sized 

 male weighs between 5 and 6 pounds, and is over i 

 foot long, and nearly 8 inches in extreme breadth, 

 that its largest nipper is nearly i foot long, and 

 nearly 8 inches in girth, and that the span of its 

 longest legs is over 2 J feet. 



Birgus is found in all the warmer parts of the 

 I nolo- Pacific, but in our locality it seems to have been 

 exterminated everywhere, except on the Nicobar Islands 

 and on South Sentinel. Its specific name, latrOy or 

 robber, is derived from tales of its climbing coconut 



