76 



BULLETIN 159, UNITED STATES NATIONAL MUSEUM 



Adult male, U.S.N. M. No. 174738; Bunguran Island, July 19, 

 1900. 



Juvenal male, U.S.N.M. No. 174739; Bunguran Island, July 5, 

 1900. 



Adult female, U.S.N.M. No. 174740; Bunguran Island, June 22, 

 1900. Length in flesh, 140 mm. 



These appear to be inseparable from the race recently described 

 from the Anamba Islands. The juvenal male and the adult male 

 No. 174737 are in process of molt of both quills and contour feathers. 

 The juvenal differs from the adult male in much lighter coloration on 

 the under parts and sides of the head. The tail resembles that of 

 the adult female, but is being replaced by the black feathers of the 

 adult plumage. From the female this juvenal male differs in its 

 darker colors above and below, particularly on the sides and top of 

 the head; the lower surface is also less yellowish; and the wings black 

 instead of dark brown. 



Measurements of these Natuna birds are given in Table 25. 



Table 25. — Measurements of specimens of Aegithina viridissima thapsina 



' Measured in the flesh by the collector. 



PYCNONOTUS SIMPLEX PERPLEXVS Chasen and Kloss 



Pycnonoius simplex perplexus Chasen and Kloss, Journ. f. Orn., Erganzungsband 

 2, p. 116, Oct. 29, 1929. (" Balambangan Island, British North Borneo.") 



Suhspecific characters. — Similar to Pycnonoius simplex simplex from 

 Sumatra," but lower parts darker, more buffy Qess yellowish) ; upper 

 surface lighter and somewhat more brownish; and iris red. 



Description. — Adult male, U.S.N.M. No. 183030, Mahakam River, 

 eastern Borneo, March 20, 1914; H. C. Raven; original number, 

 1274. Upper surface brownish olive, but the rump rather light 

 olive-brown and the upper tail coverts olive-brown; wings and tail 

 between clove brown and sepia, the wing quills, their superior coverts, 

 and the rectrices, narrowly edged exteriorly with light brownish 

 olive; sides of head and neck brownish olive, the shafts of the auric- 



" Cf. Oberholser, U. 8. Nat. Mus. Bull. 98, pp. 44, 45, June 30, 1917. ■ . i > 



