73 
Birds of Paraguay. 
This young bird has five black bands on the tail, whereas 
there are only four in the adult bird. The upper tail-coverts 
are white in the young with black bars or heart-shaped spots, 
but in the old bird the upper tail-coverts are sandy buff 
with rufous bars. 
The under surface is very different from that of the adult, 
the throat and chest being white with longitudinal brown 
centres to the feathers, the entire breast and abdomen also 
white, transversely barred with brown (these bars less distinct 
on the lower abdomen and reduced to small terminal spots 
on the under tail-coverts), and the thighs slightly more sandy 
buff and somewhat closely barred with brown. 
The old bird is altogether more rufous below, the throat 
being blackish with a few streaks of sandy buff, the feathers 
of the fore-neck and chest pale ferruginous with blackish 
shaft-lines and sandy-buff edges to the feathers, the breast 
and abdomen regularly barred with pale ferruginous on a 
sandv-buff ground, the bars rather narrower on the lower 
flanks and abdomen and reduced to narrow and incomplete 
heart-shaped or V-shaped bars on the under tail-coverts ; the 
thighs brighter sandy rufous, with dull ferruginous bars, not 
very distinct, while this colour of the thighs stands out in 
contrast to the pale colour of the abdomen. 
Mr. Bertoni has separated this bird under the name of 
Potamolegus superciliaris, var. furvicollis (cf. Bertoni, l. c. 
p. 161), but according to Dr. Ihering and Mr. C. W. Rich¬ 
mond it is inseparable from Rupornis puckerani. 
28. Urubitinga urubitinga. 
Brazilian Eagle Lath. Gen. Syn. i. p. 41 (1781: Brazil). 
Falco urubitinga Gm. Syst. Nat. i. p. 265 (1788, ex Lath.). 
Gavilan mixto chorreado Azara, Apunt. i. p. 88. no. xvii., 
juv. (1802). 
Gavilan mixto pintado Azara, t. c. p. 92. no. xviii., 
juv. 
Gavilan mixto negro Azara, t. c. p. 96. no. xx., adult. 
Urubitinga zonura Sharpe, Cat. B. Brit. Mus. i. p. 213 
(1874). 
