184 BIRDS OF LA PLATA 
being they fly to meet him hen he is still far from 
them, and hovering, with loud screams, over him, 
dash down at intervals, threatening to strike with 
their wing-spurs, coming very close to his head. 
Unable to intimidate the enemy with this show of 
violence the bird changes its tactics, and, alighting 
at some distance, counterfeits the action of a bird 
seeking its nest. With well-acted caution and secrecy 
in its manner, it runs silently along, stooping low, 
and having found a slight nest-like depression on 
the surface, sits on it, half opens its wings, and begins 
gathering all the small sticks or straws within its 
reach and carefully arranges them about it, as most 
ground-breeding birds do when incubating. Some- 
times also, like many other species, it tries to lead 
one away from the nest by feigning lameness; but 
the former instinct of seeking and sitting on an 
imaginary nest, which I have not observed in any 
other bird, seems far more complex and admirable. 
When sheep in a flock pass over the nest, the bird 
stands on it to defend its eggs; and then its loud 
cries and outspread wings often serve to bring the 
sheep, from motives of curiosity, about it. Even 
with a dozen sheep clustered round it the bird stands 
undaunted, beating their faces with its wings; but, 
unhappily for it, if the shepherd is following, the 
loud cries of the bird bring him to the spot, and the 
eggs so bravely defended are taken. 
