THE VOYAGE OF THE BEAGLE 



489 



possibility of this ; but with the Pandanus 8 the task would be 

 very much easier. I was told by Mr. Liesk that on these 

 islands the Birgos lives only on the nuts which have fallen 

 to the ground. 



Captain Moresby informs me that this crab inhabits the 

 Chagos and Seychelle groups, but not the neighbouring Mal- 

 diva archipelago. It formerly abounded at Mauritius, but 

 only a few small ones are now found there. In the Pacific, 

 this species, or one with closely allied habits, is said 9 to in- 

 habit a single coral island, north of the Society group. To 

 show the wonderful strength of the front pair of pincers, I 

 may mention, that Captain Moresby confined one in a strong 

 tin-box. which had held biscuits, the lid being secured with 

 wire ; but the crab turned down the edges and escaped. In 

 turning down the edges, it actually punched many small 

 holes quite through the tin ! 



I was a good deal surprised by finding two species of 

 coral of the genus Millepora (M. complanata and alcicornis), 

 possessed of the power of stinging. The stony branches or 

 plates, when taken fresh from the water, have a harsh feel 

 and are not slimy, although possessing a strong and dis- 

 agreeable smell. The stinging property seems to vary in 

 different specimens : when a piece was pressed or rubbed on 

 the tender skin of the face or arm, a pricking sensation was 

 usually caused, which came on after the interval of a second, 

 and lasted only for a few minutes. One day, however, by 

 merely touching my face with one of the branches, pain was 

 instantaneously caused; it increased as usual after a few 

 seconds, and remaining sharp for some minutes, was percep- 

 tible for half an hour afterwards. The sensation was as 

 bad as that from a nettle, but more like that caused by the 

 Physalia or Portuguese man-of-war. Little red spots were 

 produced on the tender skin of the arm, which appeared as if 

 they would have formed watery pustules, but did not. M. 

 Quoy mentions this case of the Millepora ; and I have heard 

 of stinging corals in the West Indies. Many marine ani- 

 mals seem to have this power of stinging : besides the Portu- 

 guese man-of-war, many jelly-fish, and the Aplysia or sea- 



8 See Proceedings of Zoological Society, 1832, p. 17. 

 •Tyerman and Bennett. Voyage, etc., vol. ii. p. 33. 



