420 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



basal phalanx of middle toe adherent to outer toe for more than half 

 its length, entirely adherent to inner toe. 



Coloration. — Above plain brownish gray, beneath plain grayish 

 white; adults with head partly yellow and lesser wing-coverts reddish 

 chestnut. 



Nidification. — Nest among twigs of thorny trees or bushes, globular 

 or retort-shaped, very bulky, composed of thorny twigs, with entrance 

 a small hole in side; eggs pale greenish blue speckled with reddish 

 brown. 



Rcmge. — Arid Lower Sonoran district of Nearctic Region. (Mono- 

 typic.) 



While evidently related to the Palsearctic genus Remiza,"' Auriparus 

 is very distinct, having the bill broader with tip less attenuate, the 

 tail rounded instead of emarginate, the outermost (tenth) primary much 

 larger (in Remiza it is almost rudimentary), and the style of coloration 

 very different. 



AURIPARUS FLAVICEPS FLAVICEPS (Sundevall). 



Adidt male.^ — Head dull gamboge or wax yellow, clearer yellow on 

 malar region, chin, and throat (where the yellow sometimes extends 

 over upper chest), more olivaceous on crown and occiput, the posterior 

 portion of forehead sometimes tinged with orange-rufous (rarely with 

 a distinct though partially concealed spot of this color); hindneck, 

 back, scapulars, rump, and upper tail-coverts plain bi'ownish gray 

 (between smoke gray and hair brown), the I'ump usually more or less 

 tinged with yellowish olive; wings and tail decidedlj^ darker with pale 

 brownish gray or grayish brown edgings, the lesser wing-coverts uni- 

 form bright reddish chestnut or bay; underparts of body pale brownish 

 gray, becoming nearly white on lower abdomen and under tail-coverts, 

 the median line sometimes faintly tinged with yellow; bill dusky horn 

 color; iris brown?; legs and feet dusky (bluish gray in life); length 

 (skins), 95-110- (107. 6); wing, 50-56 (53); tail, 46-50 (47.9); exposed 

 culmen, 8-9 (8.5); tarsus, 14.5-16 (15.4); middle toe, 8.5-10 (9.3)." 



Adult female. — Similar to the adult male, but averaging very slightly 

 duller in color, especially the yellow of head; length (skins), 93-112 



"Aegithalus of authors (not Aegithalos Hermann, 1804), ex Boie, Isis, 1822, 556. — 

 Remiza Stejneger, Proc. U. S. Nat. Mus^, ix, sig. 25, Oct. 30, 1886, 387 (type, Farm 

 penduUnus Linnseus). 



^There is no marked seasonal difference in coloration. In late spring and summer 

 the plumage is more harsh, through abrasion, and the yellow of the head is possibly 

 a little brighter, especially on the pileum. 



« Twenty-three specimens. 



