64 BULLETIN 159, UNITED STATES NATIONAL MUSEUM 



The present new subspecies from the Natuna Islands may readily 

 be distinguished from Alcippornis brunneicavda eriphaea Ober- 

 holser,' of Borneo by its more grayish (less brownish) head, paler, 

 less rufescent (more ochraceous) back, and the much paler, less rufes- 

 cent, more grayish or more purely whitish lower surface. 



As in all races of this species there is some individual variation in 

 the color of the upper parts posterior to the cervix, this area being in 

 some specimens noticeably more grayish. 



The 8 specimens obtained by Doctor Abbott are listed below: 



Adult male, U.S.N.M. No. 174811, Bunguran Island, July 6, 

 1900. "Iris pale brownish gray." 



Adult male (tj^pe), U.S.N.M. No. 174810, Bunguran Island, 

 July 18, 1900. "Irish brownish gray; bill dark horn brown, becoming 

 pale fleshy beneath at base; feet brownish leaden." 



Adult male, U.S.N.M. No. 174812, Bunguran Island, July 18, 

 1900. "Iris bluish graj^; feet pale brownish leaden." 



Adult male, U.S.N.M. No. 174813, Bunguran Island, July 18, 

 1900. "Bill dark horn brown above, pale brown beneath, a yellow 

 line along commissure. Inside of mouth and gape yellow ; feet leaden. " 



Adult male, U.S.N.M. No. 174814, Bunguran Island, July 20, 

 1900. "Iris bluish gray; bill leaden above and at tip beneath, 

 pale fleshy at base beneath; angles of mouth yellow; feet pale lavender, 

 soles yellow." 



Adult female, U.S.N.M. No. 174816, Bunguran Island, July 

 26, 1900. 



Adult female (?), U.S.N.M. No. 174815, Bunguran Island, July 

 20, 1900. "Iris bluish gray; feet pale leaden." 



First autumn female, U.S.N.M. No. 174817, Bunguran Island, 

 July 5, 1900. "Iris bluish gray; upper mandible dark horn brown; 

 lower mandible brownish yellow; feet pale leaden." 



All these examples except one are in process of molting both quills 

 and contour feathers. This exception, No. 174816, taken on July 26, 

 seems to have completed the change of wing quills and tail feathers, 

 though showing still a very few remnants of molt among the contour 

 feathers. 



One of the females (No. 174817, taken on July 5) is in process of molt 

 from the juvenal to the first autumn plumage, and has acquired 

 enough of the latter to indicate that on the posterior upper parts 

 the color is even more rufescent than in the fully adult bird. Other- 

 wise the colors appear not to differ from those of the old adult. 



Measurements are given in Table 19. 



Doctor Abbott found this species in the dense forest on Bunguran 

 Island. 



« Smithsonian Misc. Coll. vol. 74, no. 2, p. 2, Sept. 27, 1912. 



