BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 307 



the long, pointed wings, gray back, and black tail with its light 

 border that form the characters by which the bird may be recognized 

 in the field. The flight is strong and certain, and the birds alighted 

 alertly with head erect. All noted were silent. On March 17, along 

 the Rio Mendoza below Potrerillos, they were in passage downstream 

 in small parties that appeared to be in migration from the higher 

 altitudes, 



A female, taken November 29, had the base of the mandible cream 

 buff ; remainder of the bill black ; iris Hay's brown ; tarsus and toes 

 black. 



LESSONIA RUFA RUFA (Gmelin) 



Alauda rufa Gmelin, Syst. Nat, vol. 1, pt. 2, 1789, p. 792. (Buenos Aires.) 



Mathews ®2 shows that Alauda nigra Boddaert for this species is 

 antedated by Alauda nigra of the same author for another bird so 

 that the specific name becomes rufa of Gmelin. 



This ground-inhabiting flycatcher was recorded at the following 

 localities: Berazategui, Buenos Aires, June 29, 1920 (adult male 

 taken) ; Santa Fe, Santa Fe, July 4; Zapala, Neuquen, December 8 

 and 9 (two adult males shot) ; Carrasco, Uruguay, January 16, 1921; 

 Guamini, Buenos Aires, March 3 to 8 (four males, three females 

 taken) ; Tunuyan, Mendoza, March 22, 23, and 27 (adult male shot) ; 

 and Concon, Chile, April 23 (adult male taken). Twelve skins were 

 secured in all. Birds from Zapala, shot in summer, were in full 

 breeding plumage. Four males, shot in March at Guamini, were all 

 in immature plumage, in which they are similar to females, save 

 that the back is more rufescent. One shows distinct signs of molt, 

 apparently from a juvenal plumage. On this basis the young males 

 molt from a juvenal plumage into a first winter plumage that is 

 similar to the dress of the female. A specimen taken in September 

 at Conchitas, Buenos Aires (in the United States National Museum), 

 is in molt from the dull winter dress into the black adult plumage. On 

 this slender evidence it may be supposed that the young males assume 

 adult dress by a prenuptial molt in spring. An adult male, shot 

 at Tunuyan March 27, in full adult plumage, is renewing the outer 

 primaries. A skin in the United States National Museum, taken 

 in April at Conchitas, has the throat white and the lower surface 

 mottled with whitish. Other winter taken adult males do not differ 

 from breeding specimens, save for an occasional specimen with very 

 faint whitish tips on the feathers of the lower surface. It is com- 

 mon usage in recent years to consider Lessonia oreas,^^ which dif- 

 fers from nigra in larger size and whitish edgings on the inner webs 



'^Austr. Av. Rec, vol. 3, Nov. 19, 1915. 



s^Centrites areas Sclater and Salvin, Proc. Zool. Soc. London, 1869, p. 154. (Tinta, 

 Peru.) 



