Order III. ACCIPITRES.
The diurnal Birds of Prey form a natural and comparatively well-marked group showing, especially in our Indian forms,, characters separating them from all others. It is true that the Harriers superficially show certain resemblances to the Owls, which may, indeed, constitute a definite link with the Striges but, at the same time, not even a child could fail to distinguish between an Owl and any member of the present Order.
In the Accipitres the bill is strong ; the upper mandible considerably longer than the lower, with the culmen curved, the tip hooked and its outer edge perpendicular ; the basal portion is covered with a cere in which the nostrils are pierced. The feet are strong, furnished with powerful claws. A hallux is always present and there is a tufted oil-gland. The spinal feather-tract is well denned on the neck. The wing has eleven primaries. The flexor longus hallucis leads to the hallux and the flexor perforans digitorum to the other three digits but the two tendons are united by a fibrous vinculum. The ambiens muscle and the femoro-caudal are present, the accessory femoro-caudal, semitendinosus and accessory semitendinosus are absent, 'there are no bast pterygoid processes and the palate is desmognathous. Both carotids are resent and there are caeca of the intestine.
Key to Families.
A.No after-shaft to feathers............... Pandionidae, p. 3.
B.An after-shaft present.
a.Crown of head covered with down or naked............... Aegypiidae, p. 6
b.Crown of head covered with feathers…………Falconidae, p.25