Bulletin - United States National Museum - si-pddr - Smithsonian ...

BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 287
This ant bird was recorded at the following localities : Resistencia,
Chaco, July 9, 1920; Las Palmas, Chaco, July 13 to 30; Kiacho
Pilaga, Formosa, August 7 to 18; Formosa, August 24; Kilometer
25, Puerto Pinasco, Paraguay, September 1; Kilometer 80 (Puerto
Pinasco), September 9, 11, and 15; Kilometer 200 (in the same
region), September 25
; Tapia, Tucuman, April 12, 1921. The species
was uncommon both at Tapia and west of Puerto Pinasco. No
specimens were taken in the Paraguayan Chaco, so that it is possible
that birds from that region belong to another form.
MYRMORCHILUS STRIGILATUS SUSPICAX Wetmore
Myrmorchilus strigilatus suspicax Wetmobe, Journ. Washington Acad.
Sci., vol. 12, Aug. 19, 1922, p. 327. (Riacho Pilaga, near Kilometor
182, Ferrocarril del Estado, Gobernacion de Formosa, Argentina.)
The present form, described from specimens from the Riacho
Pilaga, Formosa, and the Rio Bermejo, in Argentina, differs from
typical strigilatus from Bahia, Brazil (the type locality) in moi'o
buffy superciliary stripe, browner post-ocular mark, and buffy wash
on the sides, flanks, and under tail coverts. Mr. Ridgway^* in
including Myrino7'chilus in a section containing birds with 10
rectrices was misled by an imperfect specimen as, in a small series
of skins, I find 12 tail feathers present.
At the Riacho Pilaga, Formosa, the present form was fairly
common as it was recorded on August 11, 13, and 18; eight specimens
including males and females were secured on the first and
last of these dates. Individuals recorded but not taken near Kilometer
80, west of Puerto Pinasco, Paraguay, on September 8 and
9, belong perhaps to this southern subspecies.
These birds range in pairs in dense undergrowth where it is
difficult to see them, and it was several days after my arrival at the
Riacho Pilaga before I succeeded in obtaining specimens, though
they had been heard frequently. The call note of the male is a
loud, shrill whistle that is repeated several times, and may be
represented as chee-ah chee-ah chee-ah chee-ah. This is answered
by the female in a lower tone. On the ground they walk about
easily, usually under such heav}^ cover that I had mere glimpses
of their dark forms. When excited they bobbed up near at hand
with a loud thrut thrut of the wings, at times on open limbs, where
they rested, at intervals swinging the tail over the back like the
handle of a pump, frequently through an angle of 90°.
The Anguete Indians called them keh yow.
An adult male (taken August 11), when first killed, had the biU
black, becoming neutral gray at the base of the mandible; tarsus
mouse gray; iris dull brown,
M Birds of North and Middle America, vol. 5, 1911, p. 13.