BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 105 



trees, and after some difficulty secured it. The bird, an ad'ult male, 

 rested on the top of a low shrub, balancing in the wind, but flew 

 before I came within range to circle and sail gracefully for several 

 minutes before it chose to rest. Finally, blown by a gust of wind, it 

 miscalculated its distance in passing me and fell at a long shot. On 

 the following day two were found resting in the top limbs of low 

 trees in an open marsh grown with saw grass on the border of 

 Laguna Wall, 30 kilometers farther west. When flushed they 

 swung about lightly and gracefully, seldom more than a few yards 

 from the ground. One was taken and preserved as a skeleton. The 

 Lengua Indians called this species Kdbuko. 



At the Estancia Los Yngleses near Lavalle, Buenos Aires, the 

 alcon hlanco. as this kite is Imown, was foimd on October 27, and 

 two males were taken. The first was observed as it hovered in the 

 wind 15 or 18 meters from the ground, stationary above one spot 

 of grass that it watched intently. At a hasty glance its light colora- 

 tion gave it the semblance of a gull. Another was secured from a 

 perch in the top of an ombu tree where it rested in a part of a 

 grove sheltered from wind. In one of these birds, apparently full 

 adult, the cere and upper mandible were chamois ; gape and base of 

 lower mandible slightly grayer than primuline yellow ; remainder of 

 bill black; iris orange chrome (verging toward orange rufous); 

 tarsus and toes slightly duller than apricot yellow; claws black. 

 The other male, though fully adult in other respects, retained an 

 indication of the dark spotting at the tips of some of the rectrices 

 that is found in juvenal plumage. 



Bangs and Penard®" have described the white-tailed Idte from 

 North America as Elanus leucurus majusculus (type-locality, 

 Florida) on the basis of slightly greater size. The difference be- 

 tween birds from North America and those from South America, 

 while slight from the series examined in the U. S. National Museum, 

 seems constant. A small series from Venezuela, Brazil, Paraguay, 

 Argentina, and Chile seem uniform in size and coloration. Meas- 

 urements of South American specimens that I secured as noted 

 above follows: 



88 Proc. New England Zool. Club, vol. 7, Feb. 19, 1920, p. 46. 



