86 



Smaller ; wing S 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. Buteo etythronotus exsul^ Salvin, Ibis, 1875 Masafuera I., 

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

 Masafuera Buzzard. 



Insular form ; <^ wing 375 mm. ; darker 

 blackish slate above ; $ back uniform like 

 cJ instead of red. 



151. Buteo albicaudatus alhicaudatus 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. 



Middle Texas to 

 Central 

 America ; 

 Colombia, 

 Venezuela and 

 Amazon Valley. 



flSla. Buteo albicaudatus seimeiti Allen, Bull. Am. 

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

 Grande, Texas.] 

 Sennett's White-tailed Hawk. 



Smaller ; wing o 408-412, $ 440-445 mm. ; 

 cross bars on tail and lower parts finer and 

 more broken (almost absent in oldest 

 birds). 



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

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

 gaster, B. macronychiis, B. ater, B. pictus, B. albigula, B. [Asturnia ?] cethiops et 

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

 although 1 believe some are based on immature plumages and untenable. 



