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

BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 243
The miner was local in its distribution and was found only where
areas of open sandy soil offered it a suitable habitat. Near Lavalle,
Buenos Aires, it was encountered among the dunes near the coast in
a broad area that intervened between the bare wind-swept, con-
stantly shifting sand hills just back of the beach, and the inner landward
tract that had been covered entirely by vegetation. Others
were recorded at sandy blow-outs farther inland where open sand
was exposed for more limited areas; elsewhere they were found in
one or the other of two types of country, among dunes or along
sandy hill slopes. Frequently the birds were shy and from their in-
conspicuous coloration were overlooked. Their undulating flight
carries them in sweeping bounds a meter or so above the earth, while
w^hen they alight they walk or run about among the scant growths
of vegetation that maintain a precarious foothold in the soil. With
head and body well erect they walk with nervous hesitant strides
like Fumarlus, or run for several steps and then pause. The tail in
old and young is constantly vibrated when the birds are otherwise
at rest. Among the dunes they disappear constantly over distant
ridges, so that it is difficult to follow them. The only note that I
heard them give Avas a curious song, attributed to the males, a high
pitched he he he he he he he, uttered in a laughing tone as the birds
rose from 4 to 10 meters in the air, and then descended wuth tremu-
lously vibrating wings, or as they circled and swung about in erratic
dips and curves over the undulating surface below. In the high
winds that usually prevailed in their haunts their calls seemed
ventriloquial, and may be confused with some of the notes of the
more common burrowing owl. This song seems to be given without
regard to the season of the year, as I heard it from the first week in
November to the end of April whenever I chanced to encomiter the
species. From its habit of wagging the tail this bird is often called
nienio-cola.
An adult male shot November 7 shoAved developed testes, and had
the abdomen bare, indicating that it had been incubating. An imma-
ture bird, fully grown, was taken at the same time.
GEOSITTA CUNICULARLA. HELLMAYRI Peters
Geositta cunicularia hellmayri Peters, Occ. Pap. Boston Sec. Nat. Hist.,
vol. 5, Jan. 30, 1925, p. 145. (Huanuluan, Rio Negro, Argentina.)
Two males from Zapala, Neuquen, an adult taken December 8 and
an immature specimen shot on the following day, are referred to
the present form, described recently by Peters. These two have
wing measurements of 94.2 and 96 mm., respectively, and, in addi-
tion to larger size, are slightly grayer than skins from Buenos Aires
and Uruguay.