1873.] 85 [Ridgway. 



Isclinoceles hemidactylus Gray, Gen. B. fol. pi. 10, f. 6. — Hartl., 



Syst. Ind. Azar., p. 2. 

 Geranospiza hemldactylus Bonap., Consp., 30 (sub /. gracilis). 

 Geranopus hemidactylus Pelz., Orn. Bras., 368. 

 Falco weidii brasiliensis Gray, Griff'. Cuv., 238. 



Hob. Tropical America, south of Panama. Brazil (Mus. S. I., 

 Boston Society, Philad. Acad, and Cambridge) ; Isle of Puna (Strick- 

 land) ; Panama (Cab. G. N. Lawrence). 



List of specimens. Philad. Acad., 3; Cab. G. N. Lawrence, 2 

 (Napo and Panama) ; Boston Society, 2 (BrazilJ ; Mus., Cambridge, 

 1 ( Brazil). Total, 8. 



b. var. niger Dubus. 

 Isclinoceles niger Dubus, Bull. Ac. Roy. Brux. 1848; Esg. Orn., pi. 



16. — Lafr., R. Z. 1848, 241. — Strickl., Orn. Syn. I, 125. 

 Geranospiza nigra Gray, Gen. B. fol., sp., 2. — Bonap., Consp., 30. 

 Ischnocelis aterrimus Licht., NomencL.Mus. Berol., p. 4, 1854. 

 Nisus hemidactylus Schleg., Mus. Pays-Bas, Astures, p. 53 (in part.). 



Hah. Tropical Am. north of Panama. Mazatlan (Nat. Mus.) 

 Tehuantepec (Cab. G. N. Lawrence). 



Specimens examined. Nat. Mus., 4 ; Cab. G. N. Lawrence, 1 

 (Tehuantepec). Total, 5. 



Specimens from Panama are exactly intermediate between cozru- 

 lescens from Brazil and niger from Mexico. 



Genus Buteo. — Subgenus Rupornis Kaup. 



Rupornis Kaup, 1844. Type Falco magnirostris Gmel. 



Ch. Similar to the smaller species of Buteo, but differing in hav- 

 ing five, instead of only three or four, outer quills with their inner 

 webs cut, and in the young plumage being scarcely different from the 

 adult. 



The known species of this subgenus are but two in number, the 

 R. magnirostris and R. leucorrlious — the former with several geo- 

 graphical races usually recognized as species. They have usually 

 been included in the genus Asturina along with the A. nitida. The 

 latter, however, is quite distinct subgenerically, and more nearly re- 

 lated to Leucoptemis, another subgenus of Buteo. 



SPECIES AND RACES. 



1. R. magnirostris. Above umber, or grayish brown, the tail 

 with black bands, and often tinged with rufous ; inner webs of sec- 



