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

430 BULLETIN 133, UNITED STATES NATIONAL MUSEUM
The present subspecies is characterized by the prevalence of bhick
and gray above, and in worn breeding dress appears very black in-
deed, especially on the rump. Skins from Uruguay are similar to
those from Buenos Aires, but those from Rio Grande do Sul verge
toward hunieralis as they are more brownish above. A good series
from Avia Terai and General Pinedo, in central and western Chaco,
are intermediate between dor^^ialis and tucumnnerisis as is to be ex-
pected. Some, in fact, appear identical with tucumanensis^ others
resemble dorsalis, and others are halfway between.
A puzzling circumstance is that a specimen labelled Puerto
Pinasco, September 4, 1916, taken by Cherrie, is typical of dorsalis,
while another that I secured at the same point September 3, 1920,
is as typical of the broAvn-backed hiniieralis from Brazil and north-
ward. Further specimens alone can solve the riddle presented, especially
since huineralis is the form also from Sapucay, not far from
Asuncion, Paraguay.
M. dorsalis is the best marked of the forms of the species.
5. MYOSPIZA HUMERALIS TUCUMANENSIS Bangs and Penard.
Myospiza humeralis tucunianensis Bangs and Penard, Bull. Mus. Conip.
Zool., vol. 62, April, 1918, p. 92. (Tapia, Tucuman.)
Similar to dorsalis but paler above with dark central markings
of feathers narrow, with a buffy-brown cast to upper surface. De-
cidedly paler and grayer above than humeralis.
Specimens seen from Tapia, Tucuman (the type specimen, col-
lected by Dinelli) and Victorica, Pampa. A few skins taken by
Miller and Boyle at the end of April and the beginning of May at
Avia Terai and General Pinedo, Chaco, are closely similar to the
type and may possibly be migrant individuals of this form, though
taken at the same time as birds representative of dorsalis.
The only specimen of M. h. humeralis that I secured was an adult
male taken September 3, 1920, at Puerto Pinasco, Paraguay, near
the E.io Paraguay. On this date the birds were common in open,
grassy localities, and one little colony, established in an area of
bunch grass near the river, was about ready to breed. Males sang,
from weeds or fence posts, a low ditty that may be represented as
chip-f-p chee-ee-ee-ee chee chee in the cadence and tone of a song
sparrow {Melos'piza melodia). Their call note was a faint tsif.
On the ground, they ran rapidly ahead of me from cover to cover,
or flushed wuth an undulating flight. As no others were taken those
recorded at Kilometer 80, September 9 to 20, and Kilometer 200,
September 25, west of Puerto Pinasco, are assigned here with reser-
vation.
The single male preserved is absolutely typical of the reddish
brown northern form.