86 



Smaller; wing «? 364, ? 385-410 mm.; 

 dark form ; upper parts and wings blackish 

 slate instead of light slate grey (but mantle 

 red in ?) ; below pure white in adult ; tail 

 conspicuously barred with black in addition 

 to black sub-terminal band. 



150c. Bitteo etythronotus exsul^ Salvin, Ibis, 1875 Masafuera I., 

 p. 381. [Masafuera, type in Brit. Mus.] off coast of Chile 

 Masafuera Buzzard. 



Insular form ; c? wing 375 mm. ; darker 

 blackish slate above ; 9 back uniform Uke 

 (^ instead of red. 



151. Buteo albicaudatus albicaudatus Vieill., N. 

 Diet. d'Hist. Nat., iv., p. 477 (1816). [" 5. 

 America," type loc. sugg. : Paraguay.] 

 White-tailed Hawk. 



Wing (J 430, ? 445-475 mm. ; above and 

 throat slaty-grey,darker on head and wings; 

 shoulder ferruginous ; rump and upper 

 tail-coverts white ; tail silvery grey, centre 

 feathers white, with 8 or 9 fine slaty bars 

 and sub-terminal black band ; below white, 

 axillaries and flanks barred with blackish. 



S. America, 

 from Brazil 

 (Bahia) to 

 Uruguay, 

 Paraguay, 

 Argentina and 

 Chile. 



flSla. Buteo albicaudatus sennetti Allen, Bull. Am. Middle Texas to 



Mus. N.H., v., p. 144 (1893). [Lower Rio Central 



Grande, Texas.] America ; 



Sennett's White-tailed Hawk. Colombia, 



Venezuela and 



Smaller ; wing <? 408-412, $ 440-445 mm. ; Amazon Valley, 

 cross bars on tail and lower parts finer and 

 more broken (almost absent in oldest 

 birds) . 



I The following additional forms of Buteo have been described from Chile by 

 Philippi (Arch, fiir Naturg., 1899, pp. 167-70) viz. ; Buteo melanostethos, B. pcecilo- 

 gaster, B. macronychus , B. ater, B. pictus, B. albigida, B. [Asturiiia.>] cethiops et 

 elegans, but what the respective value of these forms is I have been unable to judge, 

 although I believe some are based on immature plumages and untenable. 



