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Show 552 KEELING ISLAND. April, 18:36. a visit to the sea, no doubt for the purpose of moistening its branchire. The young are likewise hatched, and live for some time, on the coast. These crabs inhabit deep burrows, which they excavate beneath the roots of trees; and here they accumulate surprising quantities of the picked fibres of the cocoa-nut husk, on which they rest as on a bed. The Malays sometimes take advantage of their labour by collecting the course fibrous substance and using it as junk. These crabs are very good to eat; moreover under the tail of the larger ones there is a great mass of fat, which when melted sometimes yields as much as a quart bottle full of limpid oil. It has been stated by some authors that the Birgos latro crawls up the cocoa-nut trees for the purpose of stealing the nuts : I very much doubt the possibility of this; but with the Pandanus* the task would be very much easier. I understood from Mr. Liesk that on these islands the Birgos lives only on the nuts which fall to the ground. I was a good deal surprised by finding two species of coral of the genus Millepora, possessed of the property of sting, ing. The stony branches or plates when taken fresh :(rom the water have a harsh feel and are not slimy, although possessing a strong and disagreeable odour. The stinging property seems to vary within certain limits in different specimens: when a piece was pressed or rubbed on the tender skin of the face or arm, a pricking sensation was generally caused, which came on after the interval of a second, and lasted only for a short time. One day, however, by merely touching my face with one of the branches the pain was instantaneous ; it increased as usual after a few seconds, and remaining sharp for some minutes, was perceptible for half an hour afterwards. The sensation was as bad as that from a nettle, but more like that caused by the Portuguese man-of-war (Physalia). 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. The circumstance of this sting-if< See Proceedings of Zoological Society, 1832, p. 17. April, 1836. CORAL-EATING FISH, 553 ing property is not new, though it has scarcely been sufficiently remarked on. M. Quoy* mentions it, and I have heard of stinging corals in the West Indies. In the East Indian sea a stinging sea-weed also is found. There was another and quite distinct kind of coral, which was remarkable from the change of colour, which it underwent shortly after death; when alive it was of a honeyyellow, but some hours after being taken out of water, it became as black as ink. I may just mention, as partly connected with the above subjects, that there are here two species of :fish, of the genus Sparus, which exclusively feed on coral. Both are coloured of a splendid bluish-green, one living invariably in the lagoon, and the other amongst the outer breakers. Mr. Liesk assured us that he had repeatedly seen whole shoals grazing with their strong bony jaws on the tops of the coral branches.t I opened the intestines of several, and found them distended with a yellowish calcareous matter. These fish, together with the lithophagous shells and nereidous animals, which perforate every block of dead coral, must be very efficient agents in producing the finest kind of mud, and this, when derived from such materials, appears to be the same with chalk. APRIL 12TH.-In the morning, we stood out of the Lagoon. I am glad we have visited these islands : such formations surely rank high amongst the wonderful objects of this world. It is not a wonder, which at first strikes the eye of the body, but rather, after reflection, the eye of reason. We feel surprised, when travellers relate accounts of the vast extent of certain ancient ruins; but how utterly insignificant are the greatest of these, when compared to the pile of stone here accumulated by the work of various minute animals. Throughout the whole group of islands, every single atom,t • Freycinet's Voyage, vol. i., p. 597. t It has sometimes been thought (vide Quoy in Freycinet's Voyage), that coral-eating fish were poisonous ; such certainly was not the case with these Spari . t I exclude, of course, the soil which has been brought here in vessels |