54 BUBONID/E. 



At sunset the Owls begin to hoot; a short followed by a long note is 

 repeated many times with an interval of a second of silence. There is 

 nothing dreary or solemn in this performance; the voice is rather soft 

 and sorrowful, somewhat resembling the lowest notes of the flute in 

 sound. In spring they hoot a great deal, many individuals responding 

 to each other. 



In the evening they are often seen hovering at a height of forty feet 

 above the surface, and continuing to do so fully a minute or longer 

 without altering their position. They do not drop the whole distance at 

 once on their prey, but descend vertically, tumbling and fluttering as 

 if wounded, to within ten yards of the earth, and then, after hovering a 

 few seconds more, glide obliquely on to it. They prey on every living 

 creature not too large to be overcome by them. Sometimes when a 

 mouse is caught they tear off the head, tail, and feet, devouring only 

 the body. The hind quarters of toads and frogs are almost invariably 

 rejected ; and inasmuch as these are the most fleshy and succulent parts, 

 this is a strange and unaccountable habit. They make an easy conquest 

 of a snake eighteen inches long, and kill it by dealing it blows with the 

 beak, hopping briskly about it all the time, apparently to guard them- 

 selves with their wings. They prey largely on the common Coronella 

 anomala, but I have never seen one attacking 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 

 (Layostomus trichodactylus) and occasionally breed in one of their dis- 

 used burrows, as a rule they excavate a breeding-place for themselves. 

 The kennel they make is crooked, and varies in length from 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, how- 

 ever, 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, but mostly so during the breeding-season, 

 when prey is very adundarit, the floor and ground about the entrance 



