xn, c, 1 Beccari: Origin and Dispersal of Cocos Nucifera 31 
Hugo de Vries in the work above cited. My idea is that this 
great development of the pericarp may be attributed to the 
effect of the stimulus given by the crabs during the plasmatic 
period to the pericarp of the young fruits, by their efforts to 
reach the seed, which may have caused an hypertrophy of the 
tissues of the pericarp itself, leading to the production of a 
fibrous, corklike tissue of a protective nature, such as is the bark 
of a tree. In consequence and by the light nature of this 
tissue, the fruit is made capable of floating independently of any 
final cause; thus some among the many fruits produced became 
very light, and for this cause alone their dispersal was favored 
in preference to that of the heavy fruits. All this, however, 
rests on the supposition that Birgus really is in the habit of 
climbing the coconut palm and that it does so to get at the 
immature fruits. In this connection I may observe that when 
in the Moluccas I often found imperfectly matured coconuts on 
the ground, which were more or less gnawed and entirely 
emptied of their kernels. This the natives assured me was the 
work of Birgus latro. 
On the other hand Guppy writes that he never saw Birgus 
unhusk the coconuts given to them for food when kept in captiv- 
ity, but that to keep them alive it was necessary that the nuts 
should be opened for them. Hence it is not perfectly certain 
that Birgus succeeds in unhusking the coconuts when these are 
quite ripe and have fallen in the natural course to the ground.^'' 
It seems to me that if the nut were not free from the husk, 
at least partly, it would be very difficult for Birgus to get at 
the kernel of a ripe coconut in a dry state through the dense 
stratum of the fibrous cork-like tissue of the mesocarp ; whereas, 
it could easily do so in a young immature fruit. This would 
explain why Birgus is forced to climb the trees to provide itself 
with fresh nuts; whereas, it might make use of the fallen 
fruits, if it could open them. 
However, it is easy to suppose that Birgus may make use 
even of the fallen fruits by attacking those that are beginning to 
“ Guppy, H. B., The Solomon Islands, 320. 
“ The botanist who accompanied Judge Cooper on his first expedition 
to Palmyra Island would remark here that he has personally observed 
Birgus latro unhusking coconuts. He more than once watched it in its 
laborious work, tearing fiber after fiber from the nuts found on the ground. 
He has also found the nests of Birgus filled several inches thick and 
covering many square feet of ground with the fibers of the coconut, each 
fiber single. He has not observed Birgus climbing the trees, but on board 
ship a Birgus climbed to the top of a 100-foot mast. — J. F. Rock. 
