282 BULXJETIN 133, UNITED STATES NATIONAL MUSEUM 



taken by the Page expedition at Parana. The type-locality was sub- 

 sequently designated as Catamarca. Two immature specimens (fully 

 grown) that I secured April 17, 1921, on the lower slopes of the 

 Sierra San Xavier, above Tafi Viejo, Tucuman, are distinctly more 

 yellowish olive both above and below than specimens from the 

 Chaco, Parana (the Page specimens), and Uruguay, and indicate 

 that there are two forms of the bird under discussion in Argentina, 

 It is assumed that the Tucuman specimens are similar to those from 

 Catamarca so that they are given the name oleaginus. The some- 

 what duller-colored bird from farther east must take the name 

 acritus (Oberholser) described from Sapucay, Paraguay. 



On the loAver forested slopes of the Cumbre above Tafi Viejo these 

 birds were fairly common in dense growths of bushes and herbaceous 

 vegetation, but worked about under the cover of large nettlelike 

 plants where it was difficult to secure them. 



XENICOPSIS RUFO-SUPERCILIATUS ACRITUS (Oberholser) 



. Anal)a::enops acritus Oberholser, Proc. Biol. Soc. Washington, vol. 14, 

 Dec. 12, 1901, p. 187. (Sapucay, Paraguay.) 



The type of X. r. acritus is an immature bird in the somewhat 

 brighter more yellowish olivaceous plumage that distinguishes im- 

 mature from adult individuals in this species, a fact that seems 

 to have led to its separation originally. With oleagitius restricted 

 to a more western range in Catamarca and Tucuman (probably 

 north into Bolivia), the name acritus becomes available for the 

 form of northeastern Argentina and Paraguay, distinguished from 

 oleaginus by duller more grayish coloration. Typical X. r. rufo- 

 superciliatus is brighter, more rufescent on the dorsal surface, 

 especially on the wings and has the markings on the under surface 

 somewhat less sharply defined. 



An adult male taken at Las Palmas, Chaco, on July 21. 1920, was 

 the only one seen until I reached Lazcano, Uruguay, where two 

 were seen and an immature female Avas taken near the Rio Cebol- 

 lati on February 8. At Kio Negro, Uruguay, where the birds 

 were fairly common from February 15 to 18, an immature male 

 was preserved February IT, and a female of the same age on 

 February 18. The adult male from Las Palmas, in full winter 

 plumage, though a trifle brighter than two specimens from the 

 Page expedition, is duller colored than the type of the subspecies. 

 Two from Rio Negro, Uruguay, resemble the type save that they 

 have not quite completed the molt into full plumage. The one from 

 Lazcano in the same stage of molt is darker. 



These birds were found in dense thickets, usually in lowlands, 

 wliere it was more or less wet and swampy. They worked do- 



