132 BIRDS OF LA PLATA 
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 closely 
resembling the notes of other songsters, which made 
me think that the 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 Icteridz. 
CHOPI 
Aphobus chopi 
Uniform black; bill and feet black, lower mandible sulcated ; 
length 9.2 inches, Female similar but smaller and duller black. 
THE Chopi, which is said to be quite common in 
Paraguay, is only found in the north-eastern part 
of the Argentine Republic, consequently I have 
