MADAGASCAR.—My information is chiefly derived from the published charts by Captain Owen, and the accounts given by him and by Lieutenant Boteler. Commencing at the S.W. extremity of the island; towards the northern part of the _Star Bank_ (in lat. 25° S.) the coast for ten miles is fringed by a reef; coloured red. The shore immediately S. of _St. Augustine’s Bay_ appears fringed; but _Tullear_ Harbour, directly N. of it, is formed by a narrow reef ten miles long, extending parallel to the shore, with from four to ten fathoms within it. If this reef had been more extensive, it must have been classed as a barrier-reef; but as the line of coast falls inwards here, a submarine bank perhaps extends parallel to the shore, which has offered a foundation for the growth of the coral; I have left this part uncoloured. From lat. 22° 16′ to 21° 37′, the shore is fringed by coral-reefs (see Lieutenant Boteler’s “Narrative,” vol. ii, p. 106), less than a mile in width, and with shallow water within. There are outlying coral-shoals in several parts of the offing, with about ten fathoms between them and the shore, and the depth of the sea one mile and a half seaward, is about thirty fathoms. The part above specified is engraved on a large scale; and as in the charts on rather a smaller scale the same fringe of reef extends as far as lat. 33° 15′; I have coloured the whole of this part of the coast red. The islands of _Juan de Nova_ (in lat. 17° S.) appear in the charts on a large scale to be fringed, but I have not been able to ascertain whether the reefs are of coral; uncoloured. The main part of the west coast appears to be low, with outlying sandbanks, which, Lieutenant Boteler (vol. ii, p. 106) says, “are faced on the edge of deep water by a line of sharp-pointed coral-rocks.” Nevertheless I have not coloured this part, as I cannot make out by the charts that the coast itself is fringed. The headlands of _Narrenda_ and _Passandava_ Bays (14° 40′) and the islands in front of _Radama Harbour_ are represented in the plans as regularly fringed, and have accordingly been coloured red. With respect to the _East coast of Madagascar_, Dr. Allan informs me in a letter, that the whole line of coast, from _Tamatave_, in 18° 12′, to _C. Amber_, at the extreme northern point of the island, is bordered by coral-reefs. The land is low, uneven, and gradually rising from the coast. From Captain Owen’s charts, also, the existence of these reefs, which evidently belong to the fringing class, on some parts, namely N. of _British Sound_, and near _Ngoncy_, of the above line of coast might have been inferred. Lieutenant Boteler (vol. i, p. 155) speaks of “the reef surrounding the island of _St. Mary’s_ at a small distance from the shore.” In a previous chapter I have described, from the information of Dr. Allan, the manner in which the reefs extend in N.E. lines from the headlands on this coast, thus sometimes forming rather deep channels within them, this seems caused