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maritime shores. That it does not occur on some shores where 

 it might naturally be expected is attributed to enemies, among 

 whom, it may be, even primitive man is to be counted. It cannot 

 succeed in forests because it is unable to compete with other trees, 

 and it is there without means of dissemination, for its nuts fall 

 directly at the foot of the tree without any chance of being 

 carried to a distance. On the seashore, favored by its tolerance 

 of salt water, it encounters little competition, and the ocean 

 currents bear its nuts afar. 



A further argument is drawn from the singular association 

 existing between the Coco Palm and the Robber Crab. This 

 great crustacean, Birgus latro, a foot and a half in length, and 

 terrestrial in habit, can exist only where the cocoanut flourishes, 

 and is found only in the Asiatic and Pacific islands. Like its 

 relative, the Hermit Crab, its soft body is unprovided with a 

 protective covering, and to supply this want the Birgus encases 

 its abdomen in the empty shell of a cocoanut, to the cavity of 

 which its dimensions exactly correspond. Even that it climbs 

 to the tops of the palms for the purpose of detaching the nuts, 

 long regarded as a fable, has been recently ascertained to be 

 a fact. Its buccinal claw has developed into a ponderous ham- 

 mer, wherewith it staves in the germinal end of the cocoanut and 

 extracts, bit by bit, the nourishing meat. To this rich food it is 

 due that its abdomen is a reservoir of oil. 



These modifications, so extraordinary both in habits and in 

 organs, and found in the Birgus alone, of all the crab family, 

 could have been acquired by association with no other plant 

 than the Coco Palm, and to account for their acquisition demands 

 an immense period of time. And since Polynesia is the native 

 home of Birgus latro, it is logical to conclude that it is likewise 

 that of Cocos nucifera. 



The author, therefore, believes that the Coco Palm acquired 

 its specific form in Polynesia, and that its distribution therein 

 was efi^ected by the ocean currents, whose efficiency for that 

 purpose is so vigorously combated by Mr. Cook. In Asia and 

 in Malasia it has only gained a foothold under the protection of 

 man. S. B. Parish 



