Mr. Bell informs me that it is by no means common. It arrives about the end of September, and remains until the end of June, being one of the last petrels to leave the island. It is solitary in its habits, and very seldom can two nests be found in the same locality. Its breeding-place is usually near the mountain-top, in some dark gully filled with palms and fern-trees, and generally its burrow is made at the roots of the latter. It is purely nocturnal in its habits, and rarely leaves its burrow during the daytime. An egg sent to me by Mr. Bell measured 2.5in. in length by 1.9in. in breadth, and is pure-white in colour. 33. Kermadec Mutton-bird (Œstrelata mollis, Gould). This species, which Sir W. L. Buller informs me is the same as Œ. mollis, is the “mutton-bird” of the Kermadec settlers, also sometimes called “piakoia” in imitation of its cry. It arrives in immense numbers at the end of August or early in September, and breeds all over the island, but most abundantly towards the tops of the hills. Unlike most of the other petrels, it makes no burrow, but lays its single egg in a hollow at the root of a tree, or even anywhere on the bare ground. During the middle of the breeding-season they are present in extraordinary numbers, many parts of the island being converted into vast breeding-grounds. The young birds are used for food, being taken just when they commence to lose their down. They are salted and smoked, or pickled in brine. During the spring of 1889 the settlers on Sunday Island, including the Bell family and those occupying Denham Bay, collected and preserved for winter use over twelve thousand of these birds. 34. Winter Mutton-bird (Œstrelata sp.). Mr. Bell distinguishes between this bird and the preceding one. According to him, the winter mutton-bird breeds only on Meyer Island and other outlying rocks—never on the main island; and its breeding-season is during the winter months, the young birds being nearly ready to depart when the true mutton-bird arrives. I find but little difference between the two species, save that this has a more distinct dark band across the breast. At the time of my visit (August, 1887) the slopes of Meyer Island were crowded with nearly full-grown fledglings, sitting at the roots of the trees. At our approach they uttered hoarse cries, and endeavoured to escape by rolling down the hill, the old birds circling about among the trees above our heads. 35. Œstrelata Neglecta, Schl. (?) This petrel is assigned to the Kermadec Islands in the late Mr. G. R. Gray's hand-list of birds. I mention it here because