A Manual of Philippine Birds

by Richard C. McGregor

• a¹. Tail uniform, white, dirty buff, or yellowish brown, with no black bar.
  • b¹. Bill bright red for its basal half at least; body plumage not all black. Hydrocorax (p. [327])
  • b². Bill not red; plumage, except tail, all black.
    • c¹. Bill entirely black. Anthracoceros (p. [330])
    • c². Bill nearly all white. Gymnolæmus (p. [331])
• a². Tail not uniform in color, a wide black or blackish bar at its end.
  • b¹. Bill not bright red. Penelopides (p. [332])
  • b². Bill bright red. Craniorrhinus (p. [338])

Genus HYDROCORAX Brisson, 1760.

Bill and casque very large, the latter flat on top, overhanging on each side and its posterior border overhanging and extending to above the ear; bill smooth except for a few shallow furrows on base of lower mandible; chin and throat feathered; a small bare space about the eye.

Species.

• a¹. Upper outline of casque straight, its anterior end forming a projection which overhangs the culmen in front.
  • b¹. Casque and bill entirely bright red. hydrocorax (p. [327])
  • b². Casque and basal half of bill bright red, terminal half of bill whitish. mindanensis (p. [328])
• a². Upper outline of casque not straight, its anterior end sinking to the culmen and not forming an anterior overhanging projection. semigaleatus (p. [329])

289. HYDROCORAX HYDROCORAX (Linnæus).

LUZON CALAO.

• Buceros hydrocorax Linnæus, Syst. Nat. ed. 12 (1766), 1, 153.
• Hydrocorax hydrocorax Grant, Cat. Birds Brit. Mus. (1892), 17, 358; Sharpe, Hand-List (1900), 2, 64; McGregor and Worcester, Hand-List (1906), 55.

Ca-lao, Manila; reloj del monte, Spanish name.

Luzon (Meyer, Möllendorff, Everett, Steere Exp., Whitehead, McGregor); Marinduque (Steere Exp.).