THE BIRDS OF NORTHERN THAILAND 363 



able bamboo jungle and that its numbers, in a given area, vary directly 

 with the extent of this type of growth. 



The habits of this bird are so much like those of the more arboreal 

 scimitar babblers that it is of considerable interest to find it, on the 

 mountains, constantly associating with P. o. ochraceiceps and, in the 

 lowlands of Nan Province, with P. s. humilis. 



A specimen of March 24 is undergoing prenuptial molt of the 

 feathers of head and neck. Immatures collected by me, May 4 and 

 June 13, are both in the final stages of the postnatal molt, but de 

 Schauensee has taken an example, July 15, in which this molt is much 

 less advanced. All of a series of seven adults shot between May 13 

 and October 19 are in postnuptial molt. 



An adult male had the irides dull yellow ; the eyelids white, edged 

 slate; the maxilla horny brown, pale fleshy in the narial region, the 

 culmen dark brown, the extreme tip white ; the mandible and interior 

 of the mouth pale fleshy; the tarsi brown; the toes plumbeous-blue; 

 the soles yellow ; the claws pale fleshy. 



The old adult of either sex has the entire head and neck, the edge 

 of the wing, and some of the upper wing coverts pure white; the 

 remaining upperparts rufescent olivaceous-brown; the long and 

 strongly graduated tail olivaceous-brown, each rectrix tipped with 

 white ; at each side of the upper breast a black spot or bar, often pro- 

 duced to form a more or less complete gorget; the remaining under- 

 pays rufous-buff, deepest next to the spots or gorget, albescent on the 

 center of the abdomen and the under tail coverts. The juvenile differs 

 from the adult chiefly in having the upperparts, including most of the 

 crown, rufous-brown ; the rectrices tipped with grayish rufous instead 

 of white. 



The description given above will apply, in general, to any northern 

 specimen, but it is noteworthy that, though the birds of each locality 

 agree well with each other and even, in some cases, with the members 

 of one or more geographically distant populations, they tend, never- 

 theless, to differ in important degree from their nearest neighbors. 

 It is probable that three or four names will eventually be required 

 to reflect these distinctions; for the present, I leave all Thai aggre- 

 gates under the oldest available designation. 



ACTINODURA EGERTONI RAMSAYI (Walden) 



Karen Spectacled Barwing 



Actinura Ramsayi Wai.den, Ann. Mag. Nat. Hist., ser. 4, vol. 15, 1875, pp. 402- 

 403 (Karen-ni; type specimen from Kyai-pho-gyi, fide Wardlaw Ramsay, 

 in The Ornithological Works of Arthur, Ninth Marquis of Tweeddale, 1881, 

 p. 415, footnote). 



Actinodura ramsayi ramsayi, Rogers and Deignan, Proc. Biol. Soc. Washington, 

 1934, p. 91 (Doi AngKa). 



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