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

BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 119
aggressive and fought savagely, often pursuing some vanquished
competitor for some distance. A young bird two v^'eeks old, seen
on December 3, may have belonged to this species.
On January 31, 1921, on the Laguna Castillos, below San Vicente,
Uruguay, F. armillata was found in bands that rested on the low
shores and swam out into the lake as I came near. A number had
been affected by alkali in the water so that I picked up a male in
condition to skin and secured skulls from two more that lay dead
on the shore.
At Concon, Chile, on April 24, I examined one that had been
killled by a hunter.
An adult female shot on October 29 had the soft parts colored
as follows : Bill in general slightly brighter than olive yellow ; space
on culmen from above nostril to center of frontal shield, and spot
on base of bill immediately behind nostril burnt lake, shading on
outer margin to Brazil red; iris Vandyke red, slightly clouded with
duller markings; tarsus and toes in general olive lake; marginal
webs and borders of scutes washed with deep neutral gray ; spot on
rear of crus dull English red ; claws dull black.
The feet in the present species are enormous, much larger than
in other species with which it is associated, and have proportionately
broader lobes. The bird, in addition, is heavy in body and appears
large when seen at a distance. In life adults of the three coots
of this region may be distinguished without difficulty by the color
of the frontal shield and bill. In armillata a dark-red mark on the
lower margin of the shield and base of the bill crosses the other-
wise light color of these parts. In leucoftera bill and shield are
entirely light, while in i^ffrons the shield is dark red. According
to Doctor Dabbene,* F. armillata in swimming does not hold the
tail erect over the back, as is customary in ru-fifrons^ but drops it
in the manner of a tinamou.
Though the three are separated without trouble in the field, or
when freshly killed, there is often difficulty in naming dried skins.
The following notes may be of assistance in separating them
flw* Frontal plate produced posteriorly in a narrow acute point ; tail longer
(58 to 62 mm.) ; frontal plate dark red; outer web of tenth primary
usually plain (occasionally with a faint white margin) Fulica rufifrons.
(/.' Frontal shield rounded or if pointed posteriorly not greatly elongated ; tail
shorter (47 to 56.5 mm.) ; frontal plate orange or yellow; outer web of
first primary bordered with white.
?>.* Feet relatively larger ; crus more or less reddish ; secondaries plain or very
slightly margined with white at extreme tip Fulica armillata.
6.^ Feet relatively smaller ; crus greenish or yellowish ; secondaries tipped
prominently with white Fulica leucoptera.
«An. Mus. Nac. Hist. Nat. Buenos Aires, vol. 28, July 19, 1916, p. 190.
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