1883.] 
Barrows on Birds of the Lower Uruguay. 
133 
hollows of fence posts or of trees and stumps. The eggs are 
nearly white, spotted pretty finely and evenly with brown, and 
are commonly five in number. This species seems to have no 
song even during the breeding season. 
3 7. Cassicus solitaries ( Vieill.'). Boyero (Cow-herd. 
The significance of this name here is not obvious ; I suspect, 
however, that it was originally given to the Cowbifd (Molotkrus ) , 
and the present species being entirely black has been confounded 
with that bird). — Only a single specimen taken (Concepcion, 
October 12, 1880), but one or two other individuals were seen at 
about the same time. It is said to be much more abundant a 
little further up the river and in sections where the heavy swamp 
forest has not been cleared. According to these persons the 
song is very rich and beautiful, and I was often assured that 
single birds were worth as much as ten dollars in Buenos Aires. 
An allied species, Scafhidurus ater ( Vieill. ) , was not uncom- 
mon as a cage-bird. It is found along the Upper Uruguay, but 
has not yet been detected as far south as Concepcion. 
38. Icterus pyrrhopterus ( Vieill. ) . — Like the preceding, 
and with equal inaptness, called Boyero or Boyerito (Little Cow- 
herd) . 
This species is not abundant, yet was frequently met with, and 
seems to be resident at Conception through the entire year. They 
commonly go in pairs, were never seen on the ground or far from 
the swamps, and hang in any position while feeding on insects or 
berries. I do not recall ever having heard one sing, but have 
seen them caged, and they are credited with a fine song. A nest 
found December 20, 1880, contained three nearly fledged young. 
It was pensile, but only about as deep as broad, was neatly wov- 
en of fine yellow grass, and suspended among the topmost twigs 
of a small mimosa at a height of about fifteen feet from the 
ground. The eggs I did not see. 
39. Molothrus bonariensis ( Gm .). Tordo (Thrush, 
possibly so called because the European Blackbird ( Turdus me- 
rula ) is sometimes so called in Spain, and the present species 
resembles it in color. It seems probable, however, that the name 
Tordo belongs to Cassicus solitarius , and the name Boyero, by 
which that is known, to this species.) 
The common Cowbird abounds at Concepcion through the 
year, but is rather less abundant in May and June than at other 
