(RED-FLANKED WARBLING FINCH.)
+Poospiza assimilis+, _Cab. Mus. Hein._ i. p. 137; _White, P. Z. S._
1882, p. 599 (Misiones). +Poospiza lateralis+, _Barrows, Bull.
Nutt. Orn. Cl._ viii. p. 130 (Concepcion).
_Description._--Above grey, slight superciliary mark whitish; middle
of back and wings washed with rufous; rump bright rufous; tail
blackish, two lateral pairs of rectrices broadly tipped with white;
beneath grey, white in the middle of the belly; flanks and crissum
bright rufous; under wing-coverts greyish white; bill horn-colour,
lower mandible yellowish; feet pale brown; whole length 5·0 inches,
wing 2·5, tail 2·4.
_Hab._ Northern Argentina.
White found this species abundant amongst the thick weeds and grass in
the outskirts of Concepcion. He took it for _P. thoracica_, from which
it differs in its rufous rump. It is more like _P. lateralis_.