86 
Smaller; wing ¢ 364, 2 385-410 mm. ; 
dark form ; upper parts and wings blackish 
slate instead of light slate grey (but mantle 
red in 9) ; below pure white in adult ; tail 
conspicuously barred with black in addition 
to black sub-terminal band. 
150c. 
151. 
f15la. 
Buteo erythronotus exsul* Salvin, Ibis, 1875 
p- 381. [Masafuera, type in Brit. Mus.] 
Masafuera Buzzard. 
Insular form; g wing 375 mm.; darker 
blackish slate above; @ back uniform like 
6 instead of red. 
Buteo albicaudatus albicaudatus Vieill., N. 
Dict. d’Hist. Nat., iv., p. 477 (1816). [‘‘ S. 
America,” type loc. sugg.: Paraguay.] 
White-tailed Hawk. 
Wing ¢ 430, 2 445-475 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. 
Buteo allicaudatus sennettt Allen, Bull. Am. 
Mus. N.H., v., p. 144 (1893). [Lower Rio 
Grande, Texas.) 
Sennett’s White-tailed Hawk. « 
Smaller ; wing ¢ 408-412, 2 440-445 mm. ; 
cross bars on tail and lower parts finer and 
more broken (almost absent in oldest 
birds). 
Masafuera I., 
off coast of Chile 
S. America, 
from Brazil 
(Bahia) to 
Uruguay, 
Paraguay, 
Argentina and 
Chile. 
Middle Texas to 
Central 
America ; 
Colombia, 
Venezuela and 
Amazon Valley. 
1 The following additional forms of Buteo have been described from Chile by 
Philippi (Arch. fiir Naturg., 1899, pp. 167-70) viz. ; Buteo melanostethos, B. pecilo- 
gaster, B. macronychus, B. ater, B. pictus, B. albigula, B. [Asturina?| @thiops 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. 
