494 BULLETIN 186, UNITED STATES NATIONAL MUSEUM 



In the vicinity of Chiang Mai, the bands of this prinia frequent 

 the high grass at the borders of the marshes, the lush growth of sedges 

 lining the irrigation ditches, and, before the harvest, the far-flung 

 stands of rice. The species is probably common, in similar terrain, 

 throughout the northern provinces. 



A specimen from Chiang Mai, May 15, had the gonads enlarged. 

 Both the postnuptial and the postjuvenal molts are shown by the 

 two birds from Muang Fang, July 18. Examples from Chiang Mai, 

 January 23 and 24, are just beginning prenuptial molt, and this molt 

 is far advanced in the one from Ban Nam Khian, April 13. 



The adult, in winter dress, has the upperparts olivaceous-brown, 

 faintly suffused with rufescent, the feathers of the crown and mantle 

 with obsolescent darker central streaks ; the elongated tail light brown, 

 each feather showing beneath a narrow pale tip and an ill-defined 

 blackish subterminal bar ; the lores and a short supercilium pale buffy ; 

 the entire underparts buff, more rufescent on the flanks, thighs, and 

 under tail coverts, albescent on the throat and center of the abdomen. 

 In summer, it differs in having the upperparts dull grayish brown; the 

 underparts pale buff or even buffy white ; the tail shorter. 



I have discussed the specimens from Muang Fang and Ban Nam 

 Khian in my "Revision of the Indo-Chinese Forms of the Avian Genus 

 Prinia" (Smithsonian Misc. Coll., vol. 103, No. 3, 1942, p. 8). 



PRINIA FLAVIVENTRIS DELACOURI Deignan 



Indo-Chinese Yellow-bellied Prinia 



Prinia flaviventris delacouri Deignan, Smithsonian Misc. Coll., vol. 103, No. 3, 



1942, pp. 8-9 (Chiang Mai, North Thailand). 

 Prinia flaviventris flaviventris, Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 



1931, p. 150 (Chiang Mai) ; 1936, p. 118 (Chiang Mai). 



This distinctively colored prinia is apparently a very rare form in 

 northern Thailand, where I have observed only four examples: One 

 at Chiang Mai, February 18, 1931 ; one on the marshes between Chiang 

 Mai and Lamphun, July 25, 1931 ; another at the same locality, Jan- 

 uary 30, 1932; and one at Ban Hong Khaeo (Chiang Rai Province), 

 May 5, 1936. 



The few seen by me were all in tall, dense marsh vegetation at 

 decidedly wet places. 



A male (January 30) had the irides tan -brown; the edges of the 

 eyelids tan; the bill black, with the extreme tip and a narrow edging 

 to the commissure horny ; the feet and toes fleshy orange ; the claws 

 horny yellow. 



An adult male before me (collected May 5) has the lores slaty, with 

 an ill-defined whitish superior edging; the forehead, forecrown, and 



