PETREL  , the

general name of a group of birds (of which more than too species are recognized), derived from the habit which some of them possess of apparently walking on the surface of the water as the apostle St Peter (of whose name the word is ;a diminutive form) is recorded (Matt. xiv . 29) to have done . The petrels, all of which are placed in the family Procellariidae, were formerly associated with the Laridae (see GuLL), but they are now placed as the sole members of the suborder Tubinares(the name denoting the characteristic tubular structure of their nostrils) and of the order Procellariiformes (see BIRD) . They are subdivided into four groups or subfamilies: (1) Petecanoidinae (or Halodrominae), containing some three or four species known as diving-petrels, with habits very different from others of the family, and almost peculiar to high southern latitudes from Cape Horn to New Zealand; (2) Procellariinae, or petrels proper (and shearwaters); (3) Diomedeinae, or albatrosses (see MALLEMUCK); and (4) Oceanitinae, containing small sooty-black birds of the genera Cymodroma, Pealea, Pelagodroma, Garrodia and Oceanites, the distinctive nature of which was first recognized by Coues in 1864 . Petrels are archaic oceanic forms, whir great powers of flight, dispersed throughout all the seas and oceans of the world, and some species apparently never resort to land except for the purpose of nidification, though nearly all are liable at times to be driven ashore, and often very far inland, by gales of wind.' It would also seem that during the breeding-season many of them are wholly nocturnal in their habits, passing the day in holes of the ground, or in clefts of the rocks, in which they generally nestle, the hen of each pair laying a single white egg, sparsely speckled in a few species with fine reddish dots . Of those species that frequent the North Atlantic, the common Storm-Petrel, Procellaria pelagica, a little bird which has to the ordinary eye rather the look of a Swift or Swallow, is the " Mother Carey's chicken " of sailors, and is widely believed to be the harbinger of bad weather; but seamen hardly discriminate between this and others nearly resembling it in appearance, such as Leach's or the Fork-tailed Petrel, Cymochorea leucorrhoa, a rather larger but less common bird, and Wilson's Petrel, Oceaniles oceanicus, the type of the Family Oceanitidae mentioned above, which is more common on the American side . But it is in the Southern Ocean that Petrels most abound, both as species and as individuals . The Cape-Pigeon or Pintado Petrel, Da pion capensis, is one that has long been well known to mariners and other wayfarers on the great waters, while those who voyage to or from Australia, whatever be the route they take, are ' Thus Oestrelata haesitata, the Capped Petrel, a species whose proper home seems to be Guadeloupe and some of the neighbouring West-Indian Islands, has occurred in the State of New York, near Boulogne, in Norfolk, and in Hungary (Ibis, 1884, p . 202) . certain to meet with many more species, some, as Ossifraga gigantea, as large as Albatrosses, and several of them called by sailors by a variety of choice names, generally having reference to the strong smell of musk emitted by the birds, among which that of " Stink-pot " is not the most opprobrious . None of the Petrels are endowed with any brilliant colouring—sootyblack, grey of various tints (one of which is often called " blue "), and white being the only hues the plumage exhibits . The distribution of the several species of Petrels in the Southern Ocean has been treated by A .

Milne-

Edwards in the Annales des sciences naturelles for 1882 (6th series Zoologie, vol. xiii. art . 4, pp . 1-22) . (A .