388 BULLETIN 5 0, UNITED STATES NATIONAL MUSEUM 



Costa Rica). — Swann, Synopt. List Accip., pt. 2, 1919, 60, in part; Synop. 

 Accip.,ed.2, 1922, 102, part; Monogr. Birds Prey, i, 1930, 474, part (monogr.). — 

 Kennard and Peters, Proc. Boston Soc. Nat. Hist., xxxviii, 1928, 449 

 (Boquete Trail, Panama; spec; colors of soft parts). — Peters, Check-list 

 Birds of World, i, 1931, 242, part (distr.; Costa Rica; Panama). — Griscom, 

 Bull. Mus. Comp. Zool., Ixxviii, 1935, 300 (Panama: Caribbean slope of 

 Volcdn de Chiriqul). 



Leucopternis princeps princeps Friedmann, Auk, lii, 1935,30 (crit.; distr. ;meas.). 



Buteo prmceps Gray, Hand-list, i, 1869, 9, No. 72. 



Uruhitinga princeps Sharpe, Cat. Birds Brit. Mus., i, 1874, 220 (Costa Rica). 



Morphnarchus princeps Ridgway, Smiths. Misc. Coll., Ixxii, No. 4, 1920, 2. 



Genus HYPOMORPHNUS Cabanis 



Uruhitinga Lesson, Rev. Zool., ii, 1839, 132; Echo du Monde Savant, s^r. 2, vii, 

 1843, 14. (Nom.en nudum!) 



Uruhitinga Lafresnaye, Diet. Univ. Hist. Nat., ii, 1843, 786. (Type, by tau- 

 tonymy, "L'Aigle — Autour Urubitinga de Cuvier" = FaZco uruhitinga Gmelin.) 



Urubutinga (emendation) Bonaparte, Consp. Gen. Av., i, 1850, 29. 



Uruhitingua (emendation) Bonaparte, Compt. Rend., xxxvii, 1853, 809. 



Urutitinga (error typog.) Ridgway, Proc. U. S. Nat. Mus., x, 1888, 592. 



Urohitinga (lapsus) Bangs, Proc. New England Zool. Club, iii, 1902, 20. 



Oruhitinga (emendation?) Gundlach, Journ. fiir Orn., 1862, 188. 



Hypomorphnus Cabanis, Arch. fiir. Naturg., x, pt. 1, 1844, 263. (Type, by orig- 

 inal designation, Falco uruhitinga Gmelin.) 



Hypomorphinus (emendation) Gray, Gen. Birds, i, 1845, 14. 



Hypomorphus (emendation) Bonaparte, Rev. Mag. Zool., ser. 2, vi, 1854, 537. 



Hipomorphnus (emendation) Gundlach, Anal. Soc. Esp. Hist. Nat., ii, 1873, 99. 



Large long-legged rouncl-wiuged Biiteoiiidae (wing about 330-450 

 mm.) with five outer primaries sinuated on inner webs, middle toe 

 less than half as long as tarsus, culmen longer than claw of hallux, 

 the adults plain black or slate-black with one or more broad white 

 bands across tail. 



Bill rather long, the distance from base of cere to tip of maxilla 

 equal to or somewhat greater than length of middle toe, its depth at 

 base of culmen equal to about two-thirds the length (chord) of culmen 

 and nearly two-fifths greater than its Avidth at same point; culmen 

 regularly but not abruptly decurved from base, the tip of maxilla 

 form.ing a rather long unguis; gonys slightly less than half as long as 

 culmen, slightly to very slightly convex, moderately ascending ter- 

 minally; maxillary tomium with a very slight median convexity; 

 rictus slightly but decidedly anterior to anterior angle of eye; cere 

 relatively long, its length on top equal to half the length of culmen, 

 its upper outline faintly to decidedly convex proximally, its anterior 

 outline distinctly convex for upper half and concave for lower half; 

 nostril rather large, nearly circular. Wing moderately long, but 

 primaries abbreviated, the longest exceeding distal secondary by 

 about one-fourth the length of wing; fourth and fifth primaries longest, 

 the second shorter than seventh, the first a little longer than tenth; 



