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

BIRDS OF ARGENTTISrA, PARA.GXTAY, URUGUAY, AND CHILE 255
vegetation is composed of large-leaved floating forms the birds
hop about on the stems and leaves, frequently with feet and tarsi
immersed in the cold water, while they seize eagerly any insects
or other life that appear on the plants or in the water. At other
times they cling to the stalks of vertical reeds and reach out as far
as possible to dig with their bills among the small flouting plants,
resembling duckweed, that cover the surface.
Their nests are curious globular structures 6 inches in diameter,
suspended among dead rushes from about one-half to a little over
a meter above the water. Phleocryptes frequently was seen transporting
tremendous loads of wet stalks and leaves from dead
marsh growth that were molded rapidly into their round nests.
As it dried, this material was cemented firmly together by the
hardening of the slime engendered by the dampness in which it
had previously laid so that the walls of the nest were firm and
strong. A small opening led into the interior near the top, and
the structure was warmly lined with soft feathers, gathered where
they had been dropped by other avian denizens of the marsh,
and plant downs from the cat-tails and other marsh vegetation.
Though the nest of Phleocryptes was like that of a marsh wren,
there the similarity ceased, as the eggs were clear blue like those
of a robin. Three eggs appeared to be the usual number, though
I noted nests that contained only two young. Breeding begins
early as hard set eggs were taken on November 2, and two nests
containing young a week old were recorded at the same time.
Others were nest building on this same date. The three eggs taken
have a distinctly granular surface, and in color are slightly duller
than lumiere blue. They measure as follows, in millimeters : 22.1
by 15.7, 22.4 by 15.3, and 22.6 by 15.5.
The young had prominent orange margins on the opened bill
that showed plainly in the darkened interior of the nest. Their
ordure was inclosed in a capsule as in oscinine Passeriformes.
Phleocryptes is one of the few tracheophone species that decoys
easily to the loud squeaking attractive to most of the Oscines, and
came almost invariably to search for the source of the curious
noise. From their general appearance one might consider them as
sedentary, but Hudson records that they are migrant near Buenos
Aires.
LEPTASTHENURA FULIGINICEPS PARANENSIS Sdater
Leptasthenui-a paranensis P. L. Sclatkr, Proc. Zool. Soc. London, 1861,
p. 377. (Argentina.)
The present bird was encountered only near Potrerillos, Mendoza,
where it was found from 1,500 meters altitude to about 1,600 meters
in the vicinity of the Estancia El Salto. The four specimens
secured, including one male and three females, all immature (in fact,