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362 BULLETIN 133, UNITED STATES NATIONAL MUSEUM
Guamini, Buenos Aires, adult male, adult and
2, female, October 25 ;
immature females March 7, 1921 ; Zapala, Neuquen, immature male
(Juvenal dress) December 8, 1920; Tunuyan, Mendoza, adult male,
March 28, 1921. The present species may be distinguished from A.
furcatus, with which it is often associated, by the nearly straight,
much elongated hind claw, longer bill, and more distinctly streaked
plumage. Streaks on the flanks are blackish and plainly marked,
instead of indistinct as in furcatus.
Limits of subspecies in this pipit ^^ are difficult to draw. A skin
from Tunuyan, Mendoza, is clearly intermediate toward chilensis,
but seems best allotted to cori^endera. A bird in juvenal plumage
from Zapala, Neuquen, seems to belong to the typical form.
These pipits were abundant on the eastern pampas near Dolores
and Lavalle, but were not noted in numbers elsewhere. During the
breeding season, in October and November, males rose constantly
to sing on the wing, circling with direct flight and rapidly flitting
wings, a flight distinct from their undulating movement at other
times. When tired the wings were set and the bird dropped slowly
into the grass to rise and continue its evolutions in a short time. On
October 21, near Dolores, a female flushed from a nest at my feet,
ran rapidly away, and after a short flight joined her mate. The nest,
placed in a mat of dead grass stems, was a cup composed of grass
stems sunk in a little hollow so that its margin was flush with the
surface. It was entirely concealed from above except for the opening
that led into the cavity. Bottom and sides were damp from
moisture that exuded from the soil so that the eggs were wet. The
three slightly incubated eggs have a dull white ground color and
are covered heavily with an irregular wash and spotting of natal and
bone brown. The shell was very delicate. They measure 21.T by
15.4; 21.6 by 14.9; and 21.1 by 14.9 mm.
Apparently two broods may be reared, as though young were fully
grown at Zapala, Neuquen, on December 8 and 9, males were still
in song. On January 31 a breeding male (the only one of the species
seen in Uruguay) was taken on the open shore of the Laguna Cas-
tillos, near San Vicente.
Near Guamini, Buenos Aires, the birds were common in grass, in
little scattered flocks, March 7 and 8, and adults and young taken
were in molt into fall plumage. The tongue in these individuals
was blackish, being almost jet black in juveniles and paler in adults.
One was shot in the act of eating a butterfly {C'olias leshia Fabricius)
that was captured where it had sought shelter from cold and wind
in the grass. Near Tunuyan, Mendoza, these pipits were noted at
times in weed-grown fields.
6'' See Hellmayr, El Hornero, vol. 2, August, 1921, pp. 185-188.