A Manual of Philippine Birds

by Richard C. McGregor

Suborder ACCIPITRES.

This suborder includes all the hawks and eagles except the fish hawks of the genera Pandion and Polioaëtus; its members are distinguished by having the outer toe not reversible and all of the claws moderately curved, that of middle toe describing much less than a semicircle; concave or under side of each claw hollowed or grooved instead of rounded.

Family FALCONIDÆ.

Characters same as those given for the Suborder.

Subfamilies.

• a¹. Tarsus and toes longer and more slender. Accipitrinæ (p. [211])
• a². Tarsus and toes shorter and stouter. Aquilinæ (p. [222])

Subfamily ACCIPITRINÆ.

In external characters this subfamily differs very little from Aquilinæ; its members are weaker with body and legs more slender, wings and tail longer, and plumage less compact.

Genera.

• a¹. Hinder aspect of tarsus with many hexagonal scales; wing, 300 mm. or more. Circus (p. [211])
• a². Hinder aspect of tarsus without hexagonal scales; wing, 200 mm. or less.
  • b¹. Middle toe without claw about twice the culmen from anterior margin of cere. Astur (p. [216])
  • b². Middle toe without claw more than twice the culmen from anterior margin of cere. Accipiter (p. [219])