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

142 BULLETIN 133, UNITED STATES NATIONAL MUSEUM
for 200 kilometers) ; Lazcano, Urug'uay, February 7, 1921 ; Rio
Negro, Uruguay, February 18; Rio Lules, near Tucuman, Tucuinan.
April 1. At Las Palmas, Chaco, a male and two females (one pre-
served as a skeleton) were shot July 23, a male was taken at the
Riacho Pilaga, Formosa, August 9, a female at Puerto Pinasco,
Paraguay, September 8, and a male at Lazcano, Uruguay, Febru-
ary 7.
Specimens from Demerara and north Brazil appear darker than
those from the south, but the series available shows some variation
in this respect.
The aguajyiaso, a name for the jacana that has persisted since the
days of Azara and his friend Noseda, was found at times where
masses of floating vegetation choked narrow winding esteros
through the forests but more frequently was seen at the borders of
open lagoons. The birds frequented areas where aquatic plants cov-
ered the surface of the water so thickly as to present the deceptive
appearance of solid ground, where with their long widely spread
toes the jacanas sank only to a slight distance. In such situations,
though they walked about with long strides, apparently preoccu-
pied with momentous affairs, the sight of a hawk in the distance
was sufficient to send all scurrying to cover in the rushes. At times
oO or 40 jacanas were found scattered in little groups over an exten-
sive area. Though social and gregarious, they resented too close
approach on the part of their fellows with cackling calls and
threatening, upraised wings quivering above their bodies. Where
Avasherwomen came daily to wash piles of clothing that they balanced
expertly on their heads while working, in lieu of other dry
places to pile them, jacanas became tame and paid little attention
to men. In the central Chaco as the marshes dried during the winter
season the birds were restricted in range, and it was not unusual
to see them about ponds and mudholes surrounded by the thatch
huts of peons where the birds mingled with domestic ducks and
chickens of the door yards.
As jacanas walk about over the water hyacinth and other growths
one may get a suggestion of red or brown in the plumage, but on the
whole they are as inconspicuous as most other waders, so that the
flash of greenish yellow as they spread their wings in flight or ex-
tend them, perhaps as a signal, above their backs is always a pleas-
ant surprise. In flight the rapidly moving wings form a strongly
contrasted color patch on either side of the body. In general appearance
they suggest long-legged gallinules as they stalk about, a
resemblance that remains as they fly with neck and legs extended.
While feeding the birds often pull over bits of vegetation and then
peer at the exposed leaves.