HAWKE  , sinuated 1 but never notched . To these fnay be added as characters, structurally perhaps of less value, but in other respects quite as important, that the sexes differ very greatly in

size, that in most species the irides are yellow, deepening with age into orange or even red, and that the immature plumage is almost invariably more or less striped or mottled with heart-shaped spots beneath, while that of the adults is generally much barred, though the old males have in many instances the breast and belly quite free from markings . Nearly all are of small or moderate size—the largest among them being the gos-hawk (q.v.) and its immediate allies, and the male of the smallest, Accipiter limas, is not bigger than a song-thrush . They are all birds of great boldness in attacking a quarry, but if foiled in the first attempts they are apt to leave the pursuit . Thoroughly arboreal in their habits, they seek their prey, chiefly consisting of birds (though reptiles and small mammals are also taken), among trees or bushes, patiently waiting for a victim to shew with which they are often classed . The differences between all the forms above named and the much larger number here unnamed are such as can be only appreciated by the specialist . The so-called " sparrow-hawk " of New Zealand (Hieracidea) does not belong to this group of birds at all, and by many authors has been deemed akin to the falcons . For hawking see FALCONRY . (A .