110 BULLETIN 133, UNITED STATES NATIONAL MUSEUM 



on the borders of the feathers, and the head and neck blackish, 

 streaked with white. The wings have obscure mottlings of light- 

 pinkish cinnamon, and the long tail is obscurely banded with narrow 

 alternating bars of blackish and a lighter color that varies from 

 whitish and light-pinkish cinnamon to dull brown. The under sur- 

 face of the body is whitish, with streaks of blackish. The thighs 

 are obscurely barred with black, ivory yellow, and sayal brown. 



At the Riacho Pilaga, Formosa, on August 16, a pair were hunt- 

 ing along the border of a lagoon in search for food. They flew from 

 perch to perch on low rounded masses of reeds that projected from 

 floating vegetation lodged against the rushes, or dropped down to 

 the partly submerged stuff below. As they flew the white band 

 across the tail was so prominent as to attract attention at once. 

 They paid no attention to me as I drifted down on them with the 

 wind in an unwieldy cachiveo made from the trunk of a silk-cotton 

 tree, until I came near enough to secure both birds. They were 

 male and female, and though not in breeding condition, I was of the 

 opinion that they were paired. The soft parts, similar in both 

 sexes, were as follows: Bill mainly black; a space on maxilla below 

 nostril and base of mandible gray number 7 ; cere and gape chamois ; 

 iris verona brown; tarsus and toes primuline yellow; claws black. 



On August 21, while passing by train from the station at Ki- 

 lometer 182 to Formosa, I saw several of these hawks flying over 

 open marshes. At Puerto Pinasco, Paraguay, I killed an adult 

 male on September 10. The note emitted by this bird was a shrill 

 Ker-r-r-re-e-e-e^ with a cadence similar to that of a policeman's 

 whistle. The species was found, in my experience, mainly in open 

 country and appeared to hunt over marshes, where its long legs may 

 have been of service in resting on partly submerged perches or in 

 securing prey from the water. 



BUTEO POLYOSOMA (Quoy and Gaimard) 



Falco Polyosoma Quoy and Gaimard, Voy. Uranie Physicienne, Zool., 

 August, 1824, p. 92, pi. 14. (Falkland Islands.) 



A handsome adult male of this species was taken at General Koca, 

 Rio Negro, on December 2, 1920, as it rested on a pole and tore at 

 the body of a cavy held in its feet. Others were observed soaring 

 over the dry gravel hills of this region, in apiDcarance and action 

 suggesting red-tailed hawks. On December 6, at Kilometer 1097, 

 between Neuquen and Zapala, I observed a nest of this hawk placed 

 on a telegraph pole, where it was supported by the wires. The 

 owners of the structure rested in the tops of low bushes a few feet 

 away. A hawk of this species was observed near Zapala, Neuquen, 

 on December 8. Buteonine hawks were seen in the foothills of the 



