316 BULLETIN 133, UNITED STATES NATIONAL MUSEUM 



on the wing, they often suggested vireos as they searched alertly but 

 rather slowly among small limbs, a simulation that was especially 

 notable when one hoj^ped to a perch to remain quietly peering about 

 without movement of the body for a short period. Their song was 

 a curious effort that may be written as sweet swees swee-ees, given 

 slowly, with every syllable uttered distinctly and separately. A male 

 shot September 8 was nearly in breeding condition. 



EUSCARTHMORNIS MARGARITACEIVENTER MARGARITACEIVENTER (d'Orbigny and 



Lafresnaye) 



Todirostrum margaritacei venter d'ORBioNY and Lafeesnaye, Mag. Zool., 

 1837, cl. 2, p. 46. (Chiquitos, Bolivia.) 



This tody flycatcher was fairly common in the Chaco from the 

 vicinity of Resistencia north to northern Paraguay. At Resistencia, 

 males were preserved on July 8 and 9, 1920, and others were seen 

 July 10. At Las Palmas, Chaco, the species seemed less abundant 

 since the only ones observed were two females shot July 19 and 27. 

 Near the Eiacho Pilaga, where the forest as a rule was drier than 

 nearer the Rio Paraguay, Euscarthmornis was recorded in a par- 

 ticularly heavy stand of timber known as the Monte Ingles^ where 

 several were seen and a female taken on August 18. Near Kilometer 

 80, west of Puerto Pinasco, Paraguary, they were fairly common 

 from September 9 to 20; a male and female were taken September 

 10, and a second male September 20. Another male was shot Sep- 

 tember 30 on the Cerro Lorito, a wooded hill on the eastern bank 

 of the Rio Paraguay opposite the town of Puerto Pinasco. The 

 series secured, all in full plumage, vary in color individually in the 

 definiteness of streaking on the undersurface. No specimens from 

 Bolivia are available for comparison. 



These small birds frequent the lower brush at the border of heavy 

 forest, where they hop about among the twigs in search for food, 

 iilways near cover. Their light eyes give them an odd appearance. 

 Their movements, while active, are somewhat heavy, entirely dif- 

 ferent from the sprightly actions of warblers. At times tliey utter 

 a low call that resembles tsu tsu. 



A male, shot July 8, had the maxilla dull brown ; mandible a trifle 

 paler; tarsus and toes russet vinaceous; iris yellowish white, suf- 

 fused near pupil with dull buff. 



Oberholser ^® has shown grounds for transfer of the generic name 

 EuscarthTnus, to what has been known as Hapalocercus, and has 

 proposed Euscarthmornis for birds of the present group. 



"9 Auk, 1923, p. 327. 



