83 
7146. Buteo albonotatus albonoiatust Gray Cat. Mexico, Arizona 
Accip. Brit. Mus., p. 7 (1844). [Mexico, New Mexico, 
type in B. M.] (nom. nud.) : Kaup,Isis, 1847, Texas. 
cols. 329, 954. ] 
Zone-tailed Hawk. 
Wing ¢ 400-435, 2 410-445 mm. ; first 4 
quills strongly notched in adult (in im- 
mature first three notched and 4th sinuate); 
above and below black, with more or less 
of a slaty shade on mantle and chest 
(immature only showing more or less 
concealed white spots); tail black with 
broad median band of grey (showing white 
below) and remains of a second band (in 
immature with from 4 to 6 light bands). 
*146a. Buteo albonotatus abbreviatus Cab., in Surinam, 
Schomb. Reis. Guiana, iii., p. 739 (1848). Brit. Guiana, 
[Pomeroon R., Brit. Guiana, type in Berlin Venezuela, 
Mus. | Panama 
Southern Zone-tailed Hawk. (Pearl Is:); 
Brazil, Peru, 
Smaller ; wing ¢ 380-385, mm.; plumage Bolivia.’ 
similar, but black without any shade of 
slate usually shown in Mexican birds. 
1 Gray applied the name albonotatus to an immature bird, as the type in the 
Brit. Mus. proves, and without description, but Kaup’s description, unsatisfactory 
as it is, undoubtedly predates Cabanis’s name abbreviatus, so I have been obliged 
to use it. The latter name was also based on an immature bird, as I learn from 
Dr. Reichenow who examined the type in Berlin for me. The more or less con- 
cealed white spots on the plumage of some examples are a sign of immaturity, 
but are not confined to Mexican birds, and are of no value in determination. 
The actual sign of maturity lies in the tail, the oldest birds having one broad 
median grey band (showing white below) and remains of a second one, while the 
immature birds have from 6 to 4 narrower ashy bands above, according to age, 
all showing white below’ The slight difference in size is the only real distinction 
between N. American and S. American birds, but I have for several reasons 
thought it best to retain both names and so separate the former from the latter. 
Kaup’s brief reference cited in the Isis, 1847, undoubtedly applies to Gray’s 
Mexican bird, but in Jardine’s Contrib. to Ornith., 1850, p. 75, Kaup uses the 
name albonotatus again for the S. American bird. 
2 An example in Tring Mus. from Bolivia 9 (?) has a wing measurement of 
455 mm., and is therefore larger than Guianan birds, but I have been unable to see 
any other southern birds. 
