Narrative of the surveying voyages of his majesty's ships Adventure and Beagle (vol.3)

April, 1836. BiRGOS latro. 551 In the latter, the vegetation was perhaps more luxuriant than in any other part. The cocoa-nut trees generally grow separate, but here the young ones flourished beneath their tall parents, and formed with their long and curved fronds the most shady arbours. Those alone who have tried it know how deUcious it is to be seated in such shade, and drink the cool pleasant fluid of the cocoa-nut, which hangs in great bunches close by. In this island there is a large bay or little lagoon, composed of the finest white sand : it is quite level, and is only covered by the tide at high water from this large bay smaller creeks penetrated the surrounding woods. To see a field of ghttering sand, representing water, and around the border of which the cocoa-nut trees extended their tall and waving trunks, formed a singular and very pretty view. I will now briefly mention a few zoological observations which I made during our stay at these islands. I have before alluded to a crab which lives on the cocoa-nuts ; it is very common on all parts of the dry land, and grows to a mon- strous size. It is closely allied or identical with Birgos latro. This crab has its front pair of legs terminated by very strong and heavy pincers, and the last pair by others which are narrow and weak. 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 he has repeatedly seen the operation 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 com- pleted, the crab commences hammering with its heavy claws on one of these 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 hkewise 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. The Birgos is diurnal in its habits, but every night it is said to pay