AVES FALCONIDyE. 603 



Circus pii/nsfris, Less. Man. d'Orn. I. p. 105 (1828). 



Circus superciliosus, Less. Traitd d'Orn. p. 87, pi. 3, fig. i (1831). 



Butco macropterus, D'Orb. Voy. Amcr. Merid. p. 112 (1835). 



Ifiirpyiij niijcu/osa, Swains. Classif. B. II. p. 208 (1837). 



Circus megaspitus, Gould, P. Z. S. 1837, p. 10 (Maldonado) ; Darw. Voy. 



Beagle, Birds, p. 29 (1841: La Plata, July); Pelz. Reis. Novara, 



Vog. p. 14 (1865: Chili). 



Spizacircus macroptenis, Kaup, Mus. Senckenb. III. p. 258 (1845). 

 Circus macu/osus, Strickl. Orn. Syn. p. 155 (1855); Sharpe, Cat B. Brit 



Mus. I. p. 62 (1874); Gurney, List Diurn. B. Prey, p. 20 (1884); 



Sharpe, Hand-list B. I. p. 245 (1899); Martens, Hamb. Magalh. 



Sammelr. p. 5 (1900: Punta Arenas); Albert, Contr. Estud. Aves 



Chil. II. p. 507 (1901). 



GENERAL DESCRIPTION. 



Size. Adult male. 



Total length, about 21.00 inches. 



Wing, 17.00 inches. 



Culmen, 1.40 inches. 



Tail, 9.9 inches. 



Tarsus, 3.2 inches. 



Color. Adult 



General color : Above, blackish, with a slaty blue shading ; below, white, 

 with some darker streaks and spots on the chest and flanks, as well as on 

 the axillaries. 



Head : Forehead and a connecting supraciliary stripe white, as is the 

 forepart of the cheeks ; crown and sides of the face black, with a bluish 

 gloss or shade ; the facial ruff the same shade, slightly spotted with pure 

 white. 



Neck : Above, like the head and back ; the throat and foreneck and 

 the chin white or whitish ; the ruff below plainly varied with white. 



Back : Mantle black and, like the crown, somewhat shaded with a blue 

 gloss ; lower back and rump uniform black ; upper tail-coverts white, often 

 showing traces of cinnamon or rufous cross-bars. 



Tail : Two central rectrices ashy, crossed by five blackish bars and with 

 a broader subterminal band of like color tipped with dull whitish ; the rest 

 of the rectrices ashy on the outer and whitish on the inner webs and 



