492 PROCEEDINGS OF THE ACADEMY OF 



Tail dusky, narrowly tipped with white, and crossed by 5-6 narrow, 

 interrupted bars of the same. Throat and half crescent behind 

 the ear-coverts, whitish; breast more or less washed with rufous; 

 other lower parts white or buff, transversely barred with dusky. 



Remarks. In this species there is a gradual transition in 

 certain specimens between the two extremes described as the 

 plumbeous and rufous "phases." 



a. Plumbeous phase : A specimen from Bahia has the entire 

 dorsal surface clear, light bluish-plumbeous, the remiges inclining 

 more to brownish-gray. The jugulum has only a faint wash of 

 very light rufous. Another specimen from the same localit}^ has 

 each feather of the dorsal region bordered terminally with dull 

 rust}', while the entire wings are strongly washed with this color; 

 the jugulum is more extensiveby washed with a deeper shade of 

 rufous. The young birds examined agree quite closely with the 

 terms of the above diagnosis, the series exhibiting little individual 

 variation, shown chief!}' in the amount of rufous tinge on the 

 breast, which is sometimes extensive, and again entirely absent. 



b. Rufous phase: Two specimens from Brazil (Rio Janeiro 

 and Bahia) have the entire dorsal region uniform dull rufous, 

 abruptly contrasted against the dull plumbeous of the nape and 

 crown. Another has the plumbeous of the crown and nape ex- 

 tended back on the interscapulars (even tinging some of the sca- 

 pulars) which are merel}' bordered with rusty ; the effect being 

 a gradual blending or admixture on the back, of the plumbeous 

 and rufous. 



The bars beneath in these three specimens vary from plumbeous- 

 gray to brownish-black, the white bars being on different speci- 

 men of different relative width to the dark bars. The specimen 

 from Rio Janeiro has the tail-bars obsolete on the outer webs, 

 which are uniform brownish-dusky. 



In the young there is even greater variation than in the adults. 

 Two Brazilian specimens vary as follows: One is uniform, very 

 dark blackish sepia above, the back being as dark as, and very 

 little different from, the crown ; the jugulum is everywhere 

 barred, both in the white on the upper portion, and in the rufous 

 of the lower part, while the bars of the lower parts are very 

 regular and narrow, upon a white ground, almost exactly as in 

 the adult. The other specimen has the back dull rufous (as in 

 the adult), and the crown dull brownish-slate, in strong contrast; 



