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

BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 265
grown with saw grass. Though the birds were rather wrenlike in
action they were less shy than some other marsh-inhabiting
Furnariids, perhaps because this was their breeding season. One
brood of young was already on the wing, as two birds in juvenal
plumage were shot on February 5 and 7, but the adults were preparing
for a second breeding period, as a female taken February 5
was laying, and males secured February 5 and 7 were in breeding
condition. These spinetails rested often in the tops of the saw-
grass clumps where their light-colored breasts were easily visible
at some distance, or at any alarm came out with jerking tails on
lower perches to chip at me anxiously. Males had a harsh little
song that may be represented by the syllables chree-a chree-a
chree-a chree-chree-chree^ given indifferently on the wing or from
a perch. Adults taken were in very worn plumage, probably from
abrasion among the stiff grass stems among which they lived.
Specimens in juvenal plumage lack the yellow throat patch and
rufous wing coverts of adults, and have a more distinct buffy wash
over the entire plumage, noticeable especially in the superciliary
stripe and the breast.
SIPTORNIS PYRRHOPHIUS PYRRHOPHIUS (YieUIot)
Dendrocopus pyrrliophius Vieillot, Nouv. Diet. Hist. Nat., vol. 26, 1818,
p. lis. (Paraguay.)
The present form is one of rather general distribution in suitable
localities in central and northern Argentina and in Uruguay. It
was encountered at the following points: Las Palmas, Chaco, July
15 to 31, 1920 (females taken July 15 and 26)
mosa, August 7 to 18 (adult male, August 7)
; Riacho Pilaga, For-
; Victorica, Pampa,
December 23 to 29 (immature male and female, December 23 and
24)
January 28, adult and immature females, January 29, immature
; San Vicente, Uruguay, January 27 to 31, 1921 (immature male,
female, January 30) ; Lazcano, Uruguay, February 5 to 8 (adult
female, shot February 5) ; Tapia, Tucuman, April 6 to 13 (immature
male, April 9, female, April 8). No specimens of S. p. striaticeps
from Bolivia have been seen, but according to Hellmayr in this
form the streaking of the head extends down on the nape, the
secondaries and tertials are bordered with cinnamon or russet, and
the flanks are buffy brown. Typical pyrrhophius has the streaking
on the head extended only over the occiput, the secondaries and
tertials without conspicuous rufous margins and the flanks grayish
brown. The coloration of the tail in the series of pyrrhophius at
hand is variable. In many the inner web of the median rectrix is
almost wholly brown, but the extent of this color is variable as in
several it is restricted to a faint terminal spot. I can distinguish
no constant differences amone the birds from the different areas