MONOGRAPH OF THE FALCONID, 
c. Subgenus Rupornis, Kp.— Occiput without a crest; tarsus 
very high; middle toe shorter than the tarsus; tarsus and toes 
with transverse scales; 1-5 quills emarginated. The Accipitrine 
type. . 
6. A. magnirostris, Kp.; F. magnirostris, Gmel.; pl. enl. 464; 
pl. col. 86, young; Astur magnirostis, G. Gray; EF. insectivorus, 
Spix, t. viii. L’Indayé Azara, N. 30.—Large like a female N. 
Sringillarius. : 
7. A. meridionalis, Kp.; F. meridionalis, Lath., Gmel.; Circus 
rufulus, Vieill. Enc. 1216; FF. rutilans, Licht.; pl. col. 25; Aguila 
buson, Spix, Aves, Br. N. 3; Azara, N.11.— Large like Circus 
eruginosus ; rufous beneath with black bars. 
8. A. urubitinga, Kp.; F. urubitinga, Gmel.; Ag. urubitinga, 
Spix, t. i. ad.; picta, Spix, young; pl. col. 55, young; Azara, 
N. 17, 18, 20.— Tarsus 120-125 mm. long; the adult bird black. 
9. A. egquinoctialis, Kp.; IF’. equinoctialis, Lath., young; PF. 
buson, Daud., Vaill. 21; Cireaétus solitarius, Tchud. i. (ad.)—Tar- 
sus 34-94 mm. long; the adult bird black. 
d. Subgenus Thrasaétus, G. Gray.— The bill very large and 
strong; the nostrils placed under the middle of the cere; tarsus 
very robust with small scales ; claws very strong, and the inte- 
rior and hind claw greater than the toes; wings short, and the 
secondaries cover the greatest part of the quills. ‘The Aquiline 
type. 
10. A. harpyia, Kp.; Vultur harpyia, Linn.; F. destructor, 
Daud.; pl. col. 14; F. imperialis, calquin et regalis, Shaw.— Ash- 
gray with a black breast-shield. 
ll. A. azare, Kp.; F. coronatus, Azara, Temm. pl. col. 232; 
Haliaétus unifasciatus, G. Gray, Brit. Mus.—Beneath ash-gray ; 
tail with a 2” broad terminal band. 
e. Subgenus Leucopternis, Kp.—Large like Buteo ; the bill more 
slender ; the wings short, 1-5 quill emarginated ; tarsus moderately 
high; middle toe twice shorter than the tarsus ; occiput without a 
crest ; head, neck, and beneath, pure white. The Buteonine type. 
12. A. melanops, Kp.; F, melanops, Lath. ; pl. col. 105.—Lorum 
and eye region black ; head and neck with black longitudinal stripe; 
wings very short, not reaching to the upper tail-covers, 
13. A. albicollis, Kp.; F. albicollis, Lath.; F. picatus, Shaw. 
ee white, with a 3” broad terminal band ; body white. 
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