64 BIRDS OF LA PLATA 
of indignation, but the moment he retires they are 
about it again, and, even when it contains eggs or 
young birds, begin impudently carrying in feathers, 
straws, and other materials for a nest, as if they 
were already in undisputed possession. At this stage 
the Tree-Martins (Progne tapera) perhaps appear to 
complicate matters; and even if these last comers 
do not succeed in ousting the Oven-birds, they are 
sure to seize the oven when it becomes vacant, and 
the Sparrows, in spite of their earlier claim, are left 
out in the cold. But they do not take their defeat 
quietly, or, rather, they do not know when they are 
beaten, but still remain to harass their fellow 
pirates, just as they did the Oven-birds before, 
bringing straws and feathers in their beaks, and 
when forced to drop these materials and chased from 
the neighbourhood with great noise and fury by the 
Tree-Martins, it is only to return undaunted in a 
few minutes, bringing more straws and feathers. 
This Sparrow makes a rather large nest, neatly 
lined with horsehair, and lays five eggs, long, pointed, 
the entire surface thickly matted with deep chocolate 
brown. 
In rural districts this species is comparatively 
rare, not more than one or two couples being seen 
about each habitation ; and I scarcely think it would 
be too much to say that there are four or five thousand 
Chingolos for every individual Yellow Sparrow. 
Yet it is a hardy little bird, well able to hold its own, 
subsists on the same kind of food and lays as many 
eggs as the Zonotrichia; and it possesses, moreover, 
