318 BULLETIN 133, UNITED STATES NATIONAL MUSEUM 



with increasing rapidity while the bill was thrown up perpendic- 

 ularly, and terminated in an abrupt note with which the bill was 

 jerked down suddenly to its usual position, tick tick tick tick-tick- 

 tick-you. In March this species was common about swales, weed 

 patches, and cornfields near the Rio Tunuyan, in Mendoza, and was 

 apparently in migration. Specimens in fresh fall plumage are 

 brighter yellow than those secured in summer. 



PSEUDOCOLOPTERYX SCLATERI (Oustalet) 



Anaeretes sclateri Oustalet, Nouv. Arch. Mus. Paris, ser. 3, vol. 4, 1892, 

 p. 217. ("Chili.") 



An adult female was taken at Las Palmas, Chaco, on July 22, 1920, 

 a male (skeleton) July 28, and a second male at the Riacho Pilaga, 

 Formosa, August 16. The sixth and seventh primaries in the female, 

 though not minute as in the male, are noticeably shorter than the 

 fifth and eighth. There is no apparent reason for not recognizing 

 Pseudocolopteryx of Lillo - as a valid genus. 



These odd little birds were found among sedges and other low 

 growth at the borders of lagoons, often above shallow water covered 

 with fl.oating vegetation. As they worked about through such 

 growth they were so well concealed that it was difficult to locate them. 

 Occasionally one flew^ for a meter or perhaps a little more with feeble 

 flight. Before alighting, males at times produced a sudden whir, a 

 sound caused by the attenuate sixth arid seventh primaries. 



SERPOPHAGA SUBCRISTATA (Vieillot) 



Sylvia suhcristata Vieillot, Nouv. Diet. Hist. Nat., vol. 11, 1817, p. 229. 

 (Paraguay.) 



/Serpophaga suhcristata is an inhabitant of eastern Argentina, 

 Uruguay, Paraguay, and southern Brazil, where it is common in 

 forests and bush-grown pastures. It is migratory in Buenos Aires, 

 but remains through the winter in the Chaco. Thirteen specimens 

 were secured as follows (localities arranged in geographic sequence) : 

 Kilometer 80, west of Puerto Pinasco, Paraguay, September 15, 

 1920, male; Las Palmas, Chaco, July 15 and 19, male and female; 

 Resistencia, Chaco, July 8 and 9, male and female ; Rio Negro, Uru- 

 guay, February 14 and 19, 1921, male and female; San Vicente, 

 Uruguay, January 31, immature female ; Lavalle, Buenos Aires, No- 

 vember 1, 1920, female; Victorica, Pampa, December 26 and 29, male 

 and female; General Roca, Rio Negro, November 27, male and 

 female. It is supposed that Serpophaga seen at the Riacho Pilaga, 

 lormosa, August 12 to 18, 1920; at Formosa, Formosa, August 23 

 and 24; at La Poloma, Uruguay, January 23, 1921, and at Lazcano, 



■■'RfV. let. cienc. soc, (Tucuniaa), vol. 3, July, 1905, p. 48. 



