(143. 
+148a. 
143b. 
WE, 
Buteo borealis borealis (Gmel.), S.N., 1, 
p. 266 (1788). [Carolina. | 
Red-tailed Hawk. 
Size variable ; wing 3 390-400, 2 440-450 
mm. ; above blackish-brown with more or 
less of lighter variegation ; tail chestnut 
with one sub-terminal darker band and 
often remains of others; below  buffy- 
white, flanks barred or mottled and abdo- 
men heavily streaked with blackish-brown. 
Buteo borealis kridert Hoopes, Pr. Ac. Nat. 
Soc. Philad., 1873, p. 238, pl. 5. [Winne- 
bago Co., Iowa, type in Phil. Ac. Mus.] 
Krider’s Hawk. 
Wing 3 370, 2 400 mm. ; light form, pure 
white below with few or no markings ; 
tail pale rufous to grey or white, with 
blackish bars more or less obsolete and 
sub-terminal bar reduced or obliterated. 
Buteo borealis lucasanus Ridgw. Hist. N. 
Am. Birds, ii., p. 285 (1874). [Cape St. 
Lucas. | 
St. Lucas Red-tail. 
Like B. b. calurus but lighter and smaller ; 
wing 3 370-398, 2 395-420 ; sub-terminal 
tail band reduced. 
*1143c. Buteo borealis calurus Cassin, Proc. Ac. 
Nat. Sci. Philad., vii., p. 281 (1855). [Near 
Fort Webster, New Mexico, type in Phil. Ac. 
Mus. | 
Western Red-tail. 
Wing ¢ 386, 2 412-430 mm. ; strongly de- 
veloped form of B. borealis borealis, more 
E. North 
America, N. to 
Canada and 
Newfoundland, 
W. to Gt. Plains. 
Gt. Plains from 
Missouri and 
Minnesota to 
Rocky Moun- 
tains; ‘Nz tomo: 
Manitoba; S. 
in winter to 
Mexico and 
Georgia. 
Peninsula of 
Lower 
California. 
W. North 
America, beyond 
W. edge of Gt. 
Plains, E. to 
Middle Yukon, 
S.to Guatemala; 
Guadeloupe Is. 
