148 BIRDS OF LA PLATA 
and sits on a stalk or other slight elevation, from 
which it darts down to seize any insect it spies on 
the ground. Its only language is a very low whistling 
note. 
CHAT-LIKE TYRANT 
Tenioptera rubetra 
Above sandy brown, lores and superciliaries white ; wings black, 
greater coverts and outer secondaries edged with whitish, lesser 
coverts like the back, tail black, outer web of the outer tail-feathers 
and tips of others white ; below white, with black striations on the 
sides of the throat and on the breast; flanks, under wing-coverts, 
and inner webs of the primaries deep rufous; two outer pri- 
maries acuminated; length 7.5 inches. Female rather paler, 
throat and breast washed with ochraceous, and outer primaries not 
acuminated. 
I HAVE met with this bird at all seasons of the year. 
in Patagonia on the Rio Negro, and think it probable 
that it has no migration. It is seen in flocks of twenty 
or thirty individuals, and in its lively actions when 
on the wing, and in its habit of perching on a bush 
or elevation of some kind, from which it pounces 
down on an insect seen on the ground, it resembles 
other Tznioptere ; but it runs about on the ground 
a great deal, and in this respect is more like a 
Myiotheretes or Muscisaxicola. In its colour it also 
diverges widely from the typical Tznioptere in their 
black and white Dominican plumage. The whole 
upper parts are light chestnut, with a white mark on 
the side of the head; wings and tail dark, tipped 
with pale rufous; throat, breast, and belly whitish 
