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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 particularly
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 September
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.