THE BIRDS OF NORTHERN THAILAND 343 



Ixos flavula hildebrandi, Geeenway, Bull. Mus. Comp. Zool., 1940, p. 176 (Doi Aug 

 Ka, Doi Nang Kaeo). 



In the provinces west of, and including, the Khun Tan range, the 

 brown-eared bulbul is a rather common species of the evergreen forest, 

 occurring chiefly on the hills between 2,700 and 4,000 feet, rarely at 

 lower elevations where the jungle is suitable. 



This bulbul is one more of those that collect in scolding, chattering 

 flocks at flowering trees on the mountain slopes. Freshly taken exam- 

 ples usually have the face and forecrown well dusted with pollen. 



No information on the breeding season is available for our area, but 

 adults undergoing body molt have been collected on February 15 and 

 August 13, which implies that the nuptial period embraces a number 

 of months. 



My specimens had the irides red-brown ; the bill black ; the feet and 

 toes dark brown; the soles yellowish white; the claws blackish brown. 



Our race has the short crest blackish brown ( appearing black in the 

 field) ; the ear coverts shining pale brown; the mantle sullied gray; 

 the remiges blackish brown, most of them conspicuously edged along 

 the outer web with greenish yellow ; the rectrices similar, edged with 

 olive-green along the outer web near the base ; a black mustachial 

 streak; the underparts white, strongly washed with gray across the 

 breast and along the flanks. 



M. f. hildebrandti seems to have been named from a specimen which 

 showed approach to davisoni, coming as it did from near the periphery 

 of its range, but it is very misleading on this account to discard the 

 later name davisoni and use hildebrandti for the brown-headed, brown- 

 backed populations of Tenasserim and South Annam, as has been done 

 by Delacour. It seems to me preferable to recognize davisoni and 

 bourdellei, together with hildebrandti as an intermediate race. 



M. f. hildebrandti, in North Thailand, is very near bourdellei but 

 differs in having the crown blackish brown instead of black. Only 

 newly molted specimens may fairly be compared since, with wear, the 

 crown becomes browner — two bourdellei from Tongking, badly worn, 

 are inseparable in color from fresh-plumaged birds of western Thai- 

 land. 



The specimen from Khao Raem, recorded by Riley (1938) as hilde- 

 brandti, is, according to my view, true bourdellei; this race will prob- 

 ably be found also on the higher peaks of Nan Province. 



MICROSCELIS MADAGASCARIENSIS CONCOLOR (Blyth) 



Tenasserimese Black Bulbul 



Hypsipetes concolor Blyth, Journ. Asiat. Soc. Bengal, vol. 18, 1849, p. 816 

 ("Tenasserim provinces"; type specimen from Moulmein, fide Sclater, 

 Ibis, 1892, p. 77, and Finn, List of the birds in the Indian Museum, pt. 1, 

 1901, p. 94). 



