The members of this genus inhabit India and the whole of the Indian Islands, and enjoy an equally extensive range over the continent of Africa. Their natural abode is the margins of large rivers and inlets of the sea; and their chief food consists of fish, dead cetacea and carrion. 3. Ichthyiaëtus leucogaster Vol. I. Pl. 3. _Haliaëtus_ (_Pontoaëtus_) _leucogaster_, Kaup, Classif. der Säug. und Vög., p. 122. _Cuncuma leucogaster_, List of Birds in Brit. Mus. Coll., Part I. 2nd edit. p. 24. Found all round the coast of Australia, and said to extend its range to India and even to Africa; but this wants confirmation. An opinion has been lately expressed that the enormous nests observed by Captains Cook and Flinders had been constructed by some species of _Dinornis_; but it is quite evident from the account given by Flinders that they must have been formed by a bird of the Raptorial order, and I have no doubt that they were the nests of the present bird. “Near Point Possession,” says Flinders, “were found two nests of extraordinary magnitude. They were built upon the ground, from which they rose above two feet; and were of vast circumference and great interior capacity, the branches of trees and other matter, of which each nest was composed, being enough to fill a small cart. Captain Cook found one of these enormous nests upon Eagle Island, on the east coast.” Subsequently Flinders found another of these nests in which were “several masses resembling those which contain the hair and bones of mice, and are disgorged by the Owls in England after the flesh is digested. These masses were larger, and consisted of the hair of seals and of land animals, of the scaly feathers of penguins, and the bones of birds and small quadrupeds. Possibly the constructor of the nest might be an enormous Owl; and if so, the cause of the bird being never seen, whilst the nests were not scarce, would be from its not going out until dark; but from the very open and exposed situations in which the nests were found, I should rather judge it to be of the Eagle kind; and that its powers are such as to render it heedless of any attempts of the natives upon its young.”—Flinders’ Voyage, vol. i. pp. 64 and 81. The accumulation of so large a mass of materials is readily accounted for when we remember that the bird is in the habit of resorting to the same eyry for a long succession of years, and of annually carrying additional materials to reconstruct the nest. I myself found and took young birds of this species from similar nests placed on the points of rocks and promontories of the islands in Bass’s Straits. Genus HALIASTUR, _Selby._ The range of the members of this genus extends over Australia and all the islands to India. 4. Haliastur leucosternus, _Gould_ Vol. I. Pl. 4. _Falco Ponticerianus_, Shaw, Nat. Misc., pl. 389.