224 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I50 



central bar white; under surface cinnamon-brown to cinnamon-buff, 

 with foreneck lined indistinctly with shaft streaks of neutral gray ; the 

 rest, including sides and axillars, barred narrowly with black; tibia 

 and under tail coverts rufous-brown, the latter tipped with buff; 

 under surface of wing cinnamon, barred irregularly with black ; under 

 wing coverts cinnamon, tipped with buffy white along the edge of 

 the wing. 



Immature, "birds during their first season are very dark brown, 

 almost black, save for more or less white on the under surface and 

 some rufous in the primaries and greater coverts. During the second 

 year the amount of rufous in the wings is increased and invades more 

 or less of the underwing surface as well as the lesser wing coverts. 

 In the third year the under parts and head become rufous, barred 

 below, save on the throat, with blackish, but the back remains fuscous 

 brown. In fully adult plumage, apparently in the fourth year, the 

 upper back assumes an ashy shade" (Wetmore, U. S. Nat. Mus. 

 Bull. 133, 1926, p. 114). 



Measurements. — Males (10 specimens), wing 375-396 (388.8), 

 tail 176-200 (188.1), culmen from cere 23.0-24.5 (23.7), tarsus 98.7- 

 112.4 (106.7) mm. 



Females (5 specimens), wing 375-403 (388.6), tail 170-193 

 (180.2), culmen from cere 23.0-25.8 (24.6), tarsus 97.0-105.0 

 (102.3) mm. 



Resident. Fairly common on the tropical savannas of the Pacific 

 slope from Veraguas (Sona) through Code to near the lower 

 Bayano (below Chepo) in the eastern section of the Province of 

 Panama. Casual in western Chiriqui (Dolega, sight record), Bocas 

 del Toro (Changuinola, sight record, Eisenmann, Condor 1957, p. 

 250) and Comarca de San Bias (Perme, Griscom, Bull. Mus. Comp. 

 Zool., vol. 72, 1932, p. 313). 



This is a hawk of open lands, restricted, however, to the lowlands, 

 as there are no reports for it on the elevated open grass slopes of 

 the mountains. It is especially common on the savannas east of 

 Pacora, where it ranges to the last of the prairies at Ana Luz, near 

 the Rio Bayano below Chepo. On the eastern side of the Azuero 

 Peninsula I have noted it in the region between Parita, Paris, and 

 Santa Maria, in the Province of Herrera. And on March 27, 1948, 

 near Punta Mala, in southern Los Santos, I found feathers of one 

 that had been killed recently. Occasionally one is seen on Albrook 

 Field and Howard Field in the Canal Zone. 



In early morning I have observed these hawks walking about on 

 the ground, standing very tall on their long legs and moving easily 



