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BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 369
The female shot July 13 had the maxilla and tip of mandible
bone brown; base of mandible paler; tarsus tawny olive; feet
slightly yellowish; iris very dark brown.
The single bird from Uruguay is much darker on the flanks and
dorsum than those from the Argentine Chaco, differences that may
be due to immaturity or freshness of plumage, or may prove to be
of subspecific value. The species has not been recorded previously
from Uruguay.
BASILEUTERUS LEUCOBLEPHARmES LEUCOBLEPHARmES (Vieillot)
Sylvia leucotlepharldes Vieilxot, Nouv. Diet. Hist. Nat., vol. 11, 1817,
p. 206. (Paraguay.)
The present warbler was encountered in the following localities:
Eesistencia, Chaco, July 9 and 10, 1920 (one of unlmown sex taken
Las Palmas, Chaco, July 13 to 30 (adult female, July 13)
July 9) ;
Kiacho Pilaga, Formosa, August 7 and 18; San Vicente, Uruguay,
January 30 (adult female taken) ; Lazcano, Uruguay, February 5
to 8 (adult female, February 5) ; Rio Negro, Uruguay, February
14 to 18. Specimens secured in Uruguay, in full post-braeding
molt, appear darker than skins taken in winter in the Chaco, a con-
dition due perhaps to their new plumage. All are assigned to the
typical form, though the single skin in United States National
Museum that is supposed to represent B. I. superciliosus (Swain-
son) ^^ is not in satisfactory condition for comparison.
Though in the Tableau Encyclopedique et Methodique,^^ Vieillot
calls this species S. Leucohlephara^ in the original description the
specific name is spelled leucohlepharides.
Basileuterus I. calus Oberholser "'^ is a synonym of B. I. leucoble-
pharides^ since the typical form comes from Paraguay.''^
This bird inhabited dense thickets or the heavy growtli tliat
often borders clearings, where it frequented low growth or, with
constantly wagging tail, walked about on the ground. The birds
were inquisitive and came very near to me when suitable cover of-
fered, a proximity that intensified the ear-piercing tsee that served
them for call note. They were found in pairs. The song of the male
was made up of a repetition of a single, clear, whistled note repeated
several times in a slowly descending scale that in sound and cadence
suggested the song of a canyon Avren {Catherpes mexicanus) but
lacked the carrying power of the notes of that bird. A juvenile
individual Mas recorded February 5.
^ Trichas superciliosus Swainson, Anim. in Menag., 1838, p. 295. (Brazil.)
=8 Vol. 2, 1823, p. 459.
"^ Basileuterus leucoblepharus calus Oberholser, Proc. Biol. Soc. Washington, vol. 14
Dec. 12, 1901, p. 188. (Sapueay, Paraguay.)
•1 See Tabl. Encyc. Meth., vol. 2, 1823, p. 460.
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