BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 367 



Berazategui is peculiar in having the chestnut superciliary ex- 

 tended behind the eye thus suggesting viridis. An adult male, taken 

 January 30, had the tip of the culmen fuscous; rest of maxilla 

 benzo brown: base of mandible light brownish drab; rest pallid 

 quaker drab becoming fuscous at tip ; iris brick red ; tarsus and toes 

 deep green-blue gray. 



Like its congener, this pepper shrike frequented brush where it 

 hopped slowly about among the dense limbs with all the assurance of 

 a tyrant flycatcher. 



Attention was often drawn to the bird by its rollicking, warbling 

 song that carried for a considerable distance. A second song given 

 with bill pointed toward the sky resembled too too too wheur. 

 In addition to its songs, the species has several peculiar calls uttered 

 in a loud tone. Those seen in January were accompanied by grown 

 young. 



Where color may not be distinguished, the strong, heavy bill of 

 this bird is a prominent field mark. 



Family VIREONIDAE 



VIREO CHIVI CHIVI (Vieillot) 



Sylvia chivi Vieillot, Nouv. Diet. Hist. Nat., vol. 11, 1817, p. 174. (Para- 

 guay.) 



Eight skins preserved offer certain differences in coloration, but 

 may be referred to typical chivi. An adult male shot September 30, 

 1920, on the Cerro Lorito opposite Puerto Pinasco, Paraguay, may 

 represent the usual form of the type race. Four adult males from 

 San Vicente, Uruguay (January 28, 29, and 30, 1921), and a pair 

 from the Rio Cebollati, near Lazcano (February 6), are somewhat 

 duller in coloration. Deeper coloration also characterizes an adult 

 male from Tapia, Tucuman, shot April 9, 1921. 



On September 30 the species was common in the forests near the 

 Rio Paraguay, apparently newly come in spring migration, since 

 none had been seen previously. One was recorded at Asuncion, 

 Paraguay, on October 6. In eastern Uruguay, the species bred com- 

 monly on brush-grown slopes of canj^ons in the rocky hills near 

 San Vic nte (January 28 to 30, 1921), and was fairly common in 

 the dense thickets along the Rio Cebollati, below Lazcano (February 

 6 and 8). Spring and summer birds sang as persistently as does 

 V. olivaceus in the north, a species of which chivi is so much a 

 counterpart in appearance, actions, and notes that it is recognized 

 at first glance. Their smaller size and yellow-green sides and 

 flanks are apparent on close scrutiny, while in the hand it is found 

 that the iris is duller, as it varies from Rood's to Vandyke brown. 

 The birds work quietly through the limbs, pausing frequently to 



