THE BIRDS OF NORTHERN THAILAND 491 



Chiang Dao at 4,600 feet. The bird's complete absence from Doi 

 Suthep, which rises directly from the Chiang Mai lowlands, is worthy 

 of mention. 



The gray-breasted prinia is conspicuous at Chiang Mai, where, in 

 flocks of as many as twenty or thirty individuals, it travels through the 

 lower growth of brushy wastelands and the thickets bordering canals 

 and ditches ; on the hills it is necessarily restricted to extensive stands 

 of lalang. Its behavior is quite like that of the related species, the 

 members of the flock making short flights, with pumping tail, from 

 bush to bush and keeping together by an endless twittering. 



Specimens from Chiang Mai had the gonads enlarged, May 26, and 

 greatly enlarged, July 3 and September 7. The picture of the molts 

 presented by the material before me agrees well with that detailed 

 by Ticehurst and Whistler (Ibis, 1939, p. 763) from Indian series: 

 a bird of January 24 (Chiang Mai) wears full winter dress; one of 

 April 6 (Phu Kha) is in complete prenuptial molt; examples taken 

 between May 2 and September 7 (Doi Langka, Chiang Mai) are in 

 full summer dress ; one of November 26 (Chiang Mai) is in complete 

 postnuptial molt. Two skins from Chiang Mai, June 29 and Sep- 

 tember 1, show respectively postnatal molt and full juvenal plumage. 



Males in breeding dress had the irides bright brown or yellow- 

 brown; the swollen edges of the eyelids orange; the bill black; the 

 feet and toes light orange-brown or brownish flesh ; the claws horn. A 

 winter-taken male (November 19) differed in having the edges of the 

 eyelids neither swollen nor brightly colored; the bill horny yellow, 

 with the culmen dark horny brown; the feet and toes horny yellow 

 (with the fore part of the tarsus horny pink). 



In the breeding season, the adult of either sex has the upperparts 

 chaetura-black (Ridgwaj^), this color almost pure on the front, crown, 

 and nape, faintly tinged with rufescent on the mantle, rump, and 

 upper tail coverts; the wing feathers dark brown, edged along the 

 outer web with dark rufescent; the graduated rectrices brownish 

 ashy, with an ashy- white tip and a black subterminal spot (more 

 conspicuous beneath) ; the supraloral region concolorous with the 

 crown ; the tiny feathers of both eyelids slaty ; the underparts white, 

 with a broad pectoral band and the flanks deep ashy gray (the throat 

 and center of the abdomen faintly tinged with cream). In winter, 

 it differs in having the front, crown, and nape slaty brown or 

 brownish slate, changing gradually to dark olivaceous-brown, suf- 

 fused with rufescent on the lower back, rump, and upper tail coverts ; 

 the supraloral streak dark ashy, very rarely ashy white; the tiny 

 feathers of the upper eyelid ashy gray, those of the lower eyelid 

 ashy gray or mixed ashy gray and white; the underparts white (more 

 or less sullied with ashy gray on the breast and upper flanks), washed 



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