BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 113 

 RUPORNIS MAGNIROSTRIS SATURATA (Sclater and Salvin) 



Asturina saturata Sclater and Salvin, Proc. Zool. Soc. London, 1876, p. 

 357. (Apolo"' and Tilotilo, Bolivia.) 



A male in fresh fall plumage that agrees with the characters 

 assigned to this form was taken near Tapia, Tiicuman, on April 18, 

 1921. From B. m. j)uchc7'ani of areas farther east it is distinguished 

 by darker coloration throughout, and by the much bolder, heavier 

 markings of the under surface. The bird was killed as it rested in 

 a tree in low scrubby forest. On April 12 another was observed as 

 it turned in short circles far above the earth and gave the shrill 

 squealing calls common in hawks of this species more especially in 

 spring. This subspecies does not seem to have been recorded pre- 

 viously in Argentina. 



HETEROSPIZIAS MERIDIONALIS MERIDIONALIS (Latham) 

 Falco meridionalis Latham, Ind. Orn., vol. 1, 1790, p. 36. (Cayenne.) 



An adult female of this hawk taken at Kilometer 80, west of 

 Puerto Pinasco, Paraguay, on September 7, 1920, appears to be a 

 representative of the typical northern form as it has the following 

 measurements: Wing, 412; tail, 214; culmen from cere, 23; and 

 tarsus, 100 mm. The species was fairly common both at Puerto 

 Pinasco and in the Chaco to the westward from September 1 to 23. 

 At this season the birds were found in pairs and the female secured 

 showed some growth in size of the ovary, so that the breeding season 

 seemed near. The birds frequented open savannas dotted with small 

 trees that offered convenient resting places. Though in appearance 

 (save in color) and in action they resemble the red-tailed hawk 

 (Buteo horealis) they seem slower and less aggressive. On one 

 occasion I saw one stoop at a guira cuckoo on the ground but miss 

 it, and the cuckoo was then able to escape in spite of its slow, weak 

 flight. On windy days tlie hawks rested facing the wind with head 

 lowered to a level with the body, and the tail raised so as to offer 

 as little resistance to the gusts as possible. Sparrow hawks drove at 

 them occasionally but the large hawks merely dropped their heads 

 to avoid being struck, and made no attempt to punish their assail- 

 ant. The call note of this large hawk is a high pitched note resem- 

 bling kree-ee-ee-er that terminates in a drawn out wail. It suggests 

 in a way the squealing call of Buteo horealis^ but is less forceful and 

 vigorous. Occasionally a pair circled about in the air a hundred 

 meters from the earth and emitted a snarling, grunting kweh hioeh 

 hwuhrh kweh kweh. To the Anguete Indians they were known as 

 so has gookh., and to the Lenguas as nata pais shar o. 



»s So spelled in the Century Atlas of the World. 



