(CHESTNUT-SHOULDERED HANG-NEST.)
+Icterus pyrrhopterus+, _Scl. et Salv. P. Z. S._ 1868, p. 140; _iid.
Nomencl._ p. 36; _Hudson, P. Z. S._ 1870, p. 88 (Buenos Ayres);
_Durnford, Ibis_, 1878, p. 59; _Salvin, Ibis_, 1880, p. 356
(Salta); _Barrows, Bull. Nutt. Orn. Cl._ viii. p. 133 (Entrerios);
_Scl. Cat. B._ xi. p. 368. +Xanthornus pyrrhopterus+, _Burm.
La-Plata Reise_, ii. p. 493 (Paraná, Tucuman).
_Description._--Uniform black; upper lesser wing-coverts chestnut;
bill black; feet dark brown: whole length 7·7 inches, wing 3·6,
tail 3·8. _Female_ similar, but smaller.
_Hab._ S. Brazil, Paraguay, Bolivia, and Argentina.
This interesting bird, the only _Icterus_ found in the Argentine
Republic, ranges south to Buenos Ayres, where it is migratory, and
appears in small flocks of six or eight individuals in September; but
soon after arriving these little companies break up, and the birds are
subsequently found singly or in pairs in the woods along the Plata
River.
The sexes are alike in colour, but the male is considerably larger;
the whole plumage is an intense black, excepting a rufous spot on the
shoulder, seen only when the bird is on the wing; the bill is black and
curved, the body slender, and the tail long. It is a loquacious bird,
most of its tones being low and pleasing; exceedingly restless in
disposition, incessantly passing from tree to tree, jerking its long
tail and clinging to the branches in various attitudes, while searching
for insects in the decayed bark. While thus engaged it utters a great
variety of chirping and guttural sounds, interspersed with short
agreeable notes. It also has a song of considerable merit, low and
varied in tone, with a peculiar ventriloquism in many of the notes which
produce a confusing idea on the listener that the bird approaches
and recedes alternately whilst uttering them. While singing the bird
continues moving, but always concealed in the thick foliage, and it is
probably this constant turning about of the singer, and the notes coming
through leafy screens of varying density, which makes the ventriloquism
and gives so much light and shade to its mysterious melody.
The first bird of this species I shot was wounded very slightly in one
wing and fell into a stream; to my very great surprise it began singing
its usual song while floating about on the surface, making no attempt
to swim. After fishing it out it continued to sing at intervals in my
hand: how strange it was to hear this bleeding captive bird warbling out
soft, sweet notes which seemed to express only pleasant emotions! Yet
it was evident that the bird was fully alive to its danger, for it
struggled violently to escape and bit my finger savagely with its sharp
beak.
I subsequently found a nest; it was about seven inches deep, composed
entirely of lichens gathered from the boles of trees, ingeniously woven
together and suspended from the small twigs and leaves at the extremity
of a branch. There were no eggs in it, but the birds fluttered in great
trouble about me, and, what greatly surprised me, uttered a variety
of _singing_ notes, unlike their usual song, but many of them closely
resembling the notes of other songsters, which made me think that this
_Icterus_ possesses the mimicking faculty to some extent. This, however,
is a question it would be difficult to decide. It seems certain,
however, that this species is incapable of expressing any distressing
feeling, such as pain, fear, or parental anxiety, with loud harsh notes
like other birds. It is much to be regretted that Azara, who found this
species common in Paraguay, did not pay more attention to its habits and
language, which make it specially interesting even in a family so rich
in strange habits as the _Icteridæ_.