MONOGRAPH OF THE FALCONIDA, 
mus, Ord; Sparv. platypteraus, Vieill.—Head and bill 65, and the 
sealed part of the tarsus 36 mm. long. N. America. 
7. Buteo lineatus, Jard.; F. lineatus, Gmel.; Wils, 53-2; hie. 
malis, Wils. 35-1, young—The wings 332 mm. long. N. America, 
8. Buteo erythronotus, G. Gray ; Haliaétus erythronotus, King; 
Buteo unicolor et tricolor, D’Orb.; varius, young, Gould.— The 
wings 398-429; tail 190-196 mm. long. @hili, Falkland Islants, 
Strait of Magellan. ! 
9. Buteo infulatus, Kp., Brit. Mus. — The wings 364; tail 200; 
tarsus 80, middle toe 35 mm. long; front white. A young bird, 
and nearly connected to the B. lineatus. Galapagos Islands. 
10. Buteo borealis, Swains.; F’. borealis et jamaicensis, Gmdl.; 
Wils. 52-2, ad.; F. leverianus, Wils. 52-1, young ; F. ferrugineo- 
cauda, Vieill. Ois, d’Am. t. 6; B. americanus, Vieill.; Accipiter 
ruficaudus, Vieill. Ois. d’Am. t. 44, bis.—The wings 375 ; tail 285: 
tarsus 80 mm. long. N. America. 
d. Subgenus Ichthyoborus, Kp.—The bill a little elevated; 15 
quills slenderly emarginated ; toes with distinct transverse scales: 
sole of the toes with pointed warts (a fisher), The Aguiline or 
Pandion and Pelicanoid type. 
11. Buteo nigricollis, Kp. ; F. nigricollis, Lath.; F. busarellus, 
Daud.; Vaill, 20; Cireus leucocephalus, Vieill; Azara, N. 13; 
Aq. milvoides, Spix, 1 ad.—The total plumage rufous. S. America. 
e. Subgenus Buteo, Kp.—Tarsus before and behind with transverse 
Scales; the wings extend to the tip of the tail ; 1-4 quill distinctly 
emarginated ; the sole of the toes with obtuse warts. The Buteo- 
nine type. 
12. Buteo augur, Riipp.; B. augur et hydrophilus, Ripp. 
Neue Wirbelth, t. 16, 17.—Adult, tail rafous, with a black terminal 
band ; the secondaries ash-gray, with black bars; tarsus (female) 
90, middle toe 40 mm. long. Very nearly connected with the B. 
jackal of the Cape. N. Africa. 
13, Buteo jackal, Cuv.: Vaill. 16.— Plumage black, white, aud 
rufous; tail rufous, with black terminal band; secondaries ash- 
coloured, with dark spots and black terminal band ; tarsus 80-89; 
middle toe 42-43; tail 190-196 mm. long. Cape. 
14. Buteo rujinus, Riipp. Fauna Ab.: B. longipes, Jard.—Middle 
toe shorter than the sealed part of the tarsus. Asia, accidental in 
Africa, 
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