30 BIRDS OF LA PLATA 
first, they take to alighting at the entrance of the 
coveted home; this is a sort of declaration of war, 
and marks the beginning of hostilities. The Oven- 
birds, full of alarm and anger, rush upon and repel 
them as often as they approach; they retire before 
this furious onset, but not discomfited, and only 
warbling out their gay, seemingly derisive notes in 
answer to the outrageous, indignant screams of their 
enemies. Soon they return; the scene is repeated ; 
and this desultory skirmishing is often continued 
for many days. 
But at length the lawless invader, grown bolder, 
and familiar with his strength and resources, will no 
longer fly from the master of the house; desperate 
struggles now frequently take place at the entrance, 
the birds again and again dropping to the ground 
clutched fiercely together, and again hurrying up 
only to resume the combat. Victory at last declares 
itself for the aggressors, and they busy themselves 
carrying in materials for their nest, screaming their 
jubilant notes all the time as if in token of triumph. 
The brave and industrious Oven-birds, dispossessed 
of their home, retire to spend their childless summer 
together, for the male and female never separate ; 
and when the autumn rains have supplied them 
with wet clay, and the sense of defeat is worn 
off, they cheerfully begin their building operations 
afresh. 
This is not, however, the invariable result of the 
conflict, To the superior swiftness of the Martin 
the Oven-bird opposes greater strength, and, it might 
