40 BIRDS OF LA PLATA 



dealing it blows with the beak, hopping briskly about 

 it all the time, apparently to guard themselves with 

 their wings. They prey largely on the common 

 Coronella anomala, but I have never seen one at- 

 tacking a venomous species. When they have young 

 many individuals become destructive to poultry, 

 coming about the houses and carrying off the chickens 

 and ducklings by day. In seasons of plenty they 

 destroy far more prey than they can devour; but 

 in severe winters they come, apparently starving, 

 about the houses, and will then stoop to carry off 

 any dead animal food, though old and dried up 

 as a piece of parchment. This I have often seen 

 them do. 



Though the Owls are always on familiar terms 

 with the Vizcachas {Lagostomus trichodactylus) and 

 occasionally breed in one of their disused burrows, 

 as a rule they excavate a breeding-place for them- 

 selves. The kennel they make is crooked, and varies 

 in length £rom four to twelve feet. The nest is placed 

 at the extremity, and is composed of wool or dry 

 grass, often exclusively of dry horse-dung. The 

 eggs are usually five in number, white, and nearly 

 spherical ; the number, however, varies, and I have 

 frequently found six or seven eggs in a nest. After 

 the female has begun laying the birds continue 

 carrying in dry horse-dung, until the floor of the 

 burrow and a space before it is thickly carpeted with 

 this material. The following spring the loose earth 

 and rubbish is cleared out, for the same hole may 

 serve them two or three years. It is always untidy. 



