THE BIRDS OF NORTHERN THAILAND 75 



bare skin on the sides of the abdomen and inside the thighs livid white ; 

 the feet and toes mottled pink and white ; the soles light brown ; the 

 claws black. 



An immature specimen differed in having the irides dull brown ; the 

 cere blue-gray ; the maxilla dark horn-brown ; the mandible blue-gray, 

 horny at the tip ; the naked skin of the head livid white ; the feet and 

 toes livid white ; the claws black. 



This vulture has very broad wings and a comparatively short wedge- 

 shaped tail. The naked head and wattled neck, the feet, and a bare 

 area on the inner thigh are reddish and conspicuous in flight. 



The adult is generally black, with a large chest patch of pure white 

 down, continued up the sides of the neck to meet a ruff of black feathers 

 on the back of the neck ; it has a similar patch of white down along 

 either flank. The immature has the general plumage brown and the 

 head and neck covered with white down. 



PSEUDOGYPS BENGALENSIS (Gmelin) 



Indian White-backed Vulture 



[Vultur] bengalensis Gmelin, Systema naturae, vol. 1, pt. 1, 1788, pp. 245-246 

 (Bengal). 



Pseudogyps bengalensis, Gyldenstolpe, Kungl. Svenska Vet.-Akad. Handl., 1916, p. 

 131 (Chiang Mai) ; Ibis, 1920, p. 743 ("Throughout the whole country"). — de 

 Schauensee, Pi'oc. Acad. Nat. Sci. Philadelphia, 1928, p. 576 (Den Chai). — 

 Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 1931, p. 164 (Chiang Mai, Doi 

 Suthep) ; 1936, p. 77 (Chiang Mai, Doi Suthep). 



The white-backed vulture is very common throughout our area, but, 

 unlike the preceding species, it has not been observed at high altitudes. 



While the vultures are feeding they can be closely approached, and 

 the sight of a large number of these birds, together with a few king 

 vultures, devouring a dead cow or buffalo, is a familiar but wholly re- 

 pulsive one. The heavier and stronger Sarcogyps takes its fill first, 

 while the white backs wait respectfully; the leaving of the king is a 

 signal for the impatient hordes to crowd forward over the cadaver. 

 They are quarrelsome birds, and the beating of wings, the craning of 

 long snaky necks, the growling and hissing that take place, especially 

 when two individuals begin to devour a strip of entrals from the oppo- 

 site ends, are horrible beyond description. As the observer comes too 

 near, they spread the great wings and cover the ground with clmnsy 

 leaps ; they seem incapable at any time of taking to the air without this 

 preliminary, and when gorged are highly unwilling, if not unable, to 

 leave the ground. After the feast has been devoured to the bones, the 

 banqueters stand torpidly about the remains or move off only to the 

 branches of the nearest trees, which they line while digestion takes 

 place. 



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