52 BULLETIN 93, UNITED STATES NATIONAL MUSEUM. 



Immature female, No. 171041, U.S.N.M.; Pulo Manguan, August 

 31, 1899. Length, 203 mm. 



All the adult birds are in process of molt, involving chiefly the 

 wing and tail feathers, though the type (No. 170954, U.S.N.M.) 

 has the feathers of most of the chin and forepart of the head in their 

 sheaths, and all the other specimens have some molting feathers on 

 the body. 



The adult female differs from the adult male in her shorter tail; 

 smaller general size; dull, nonmetallic, bluish slate-colored upper 

 parts, throat, and breast, the pileum with a brownish tinge; duller, 

 more brownish wings and tail; tawny edgings on some of the upper 

 wing-coverts; and lighter shade of the posterior lower parts, the 

 thighs and middle of abdomen particularly paler. 



The immature male (No. 171042, U.S.N.M.) obtained by Doctor 

 Abbott is in process of molt, and is changing from the iuvenal into 

 the completely adult plumage. It differs from the adult male in 

 partly brown head and back, the black feathers of the adult plumage 

 having only partly replaced those of the iuvenal dress; short, more 

 brownish tail: much more brownish wings, the remiges edged partly 

 on exterior webs with tawny, the greater and median wing-coverts 

 broadly tipped with the same (the lesser coverts have assumed the 

 black of adult plumage); sides of head and of neck dull dark brown, 

 mixed with tawny ochraceous, also with a few black feathers, leaving 

 only the center of chin, throat, and jugulum glossy black; posterior 

 lower parts of a paler rufous. 



The immature female (No. 171041, U.S.N.M.) is in what appears 

 to be juvenal plumage, and differs from the adult female in having 

 the upper surface lighter, decidedly more brownish, the pileum, 

 back, and scapulars being particularly brown; the rump with an 

 anterior band of tawny, and all the white washed with tawny; tail 

 more brownish, all the white tips, excepting those of the two outer 

 pairs, much mottled with brown; wings more brownish; remiges 

 broadly edged on outer webs with dull tawny; median wing-coverts 

 more conspicuously tipped with tawm^ ochraceous; lesser wing- 

 coverts with a broad white streak along the shaft or on the outer 

 web of each feather; forehead, lores, superciliary stripe, orbital 

 region, and cheeks, dull white, finely mixed with brownish gray; 

 sides of neck slate gray; auriculars slate gray, streaked with whitish; 

 chin buffy white; a buffy ochraceous spot on upper throat just back 

 of the chin; rest of throat rather light gray, washed and streaked 

 broadly with buff; posterior lower parts much paler than in the 

 adult. This example shows only slight indications of molt. 



Doctor Abbott reported this species as common on Pulo Siantan 

 from August 19 to September 6, 1899; and observed it also on Pulo 

 Kelong, September 1, 1899. 



