Haliastur Selby, Oat. Gen. et Subgen.
Type p. 3 (1840). Type, Falco indus Bodd.
The genus Haliastur leads from the Sea-Eagles to the Kites, being nearer the latter than the former. The bill is fairly large, compressed, slightly curved at the base and sharply so at the tip ; festoon small but/distinct; nostril almost round and oblique; wings very long, extending to or beyond the tip of the tail; fourth primary longest, first about equal to two-thirds length of fourth ; tail rather long and slightly rounded ; tarsi short and feathered above; the naked portion scutellated in front and on the toes, elsewhere with hexagonal scales, small at the sides, large behind, where in young birds they form broad scutse; soles furnished with tiny prickly scales; outer toe longer than inner; claws curved and moderately strong.
The genus contains one species, which is found throughout the Oriental and Australian regions.
Key to Subspecies.
A.Streaks on head and breast well defined. H, i. indus, p. 118.
B.Streaks on head and neck very narrow and less distinct.........H. i. intermedius *, p. 120.