Like all the American aborigines the Onas feed principally upon meat, and this meat was, in former years, obtained from the guanaco. The guanaco roamed about in large herds upon the pampas and grassy lowlands; regions now in use as sheep-farms. The guanaco, like the Indian, is forced to the barren interior mountains, where life is a hard struggle against storms and barrenness and perennial snows. Owing to the present greater difficulty of hunting these animals and their reduced numbers, the Ona has taken most naturally to the sheep which have been brought to occupy these lands. That the sheep are owned by other men is a fact not easily recognised by Indians, to whom the world of Fuegian wilderness has always been free. The many thousands of _guanaco blanco_, as the Onas call sheep, grazing peacefully upon the Indian hunting-grounds, make a picture full of irresistible temptation, as the aborigines, hungry and half naked, look from icy mountain forests down over the plains. Shall we call them thieves if, while their wives and children and loved ones are starving, they boldly descend and, in the face of Winchester rifles, take what to them seems a product of their own country? Unfortunately, the Indians have had so many causes for revenge against the white invaders, that they no longer capture sheep, as they did primarily, to satisfy the pangs of hunger, but to obtain vengeance. The wholesale manner in which they do this, however, would make a beggar of an ordinary farmer in a single night. In the neighbourhood of Useless Bay they have been known to round up two thousand sheep in one raid, and they seldom now take less than a few hundred at a time. While stopping at a farm on the Rio Grande I had an opportunity of being in close proximity to this kind of warfare. Two Indians came in and asked for an interview with the chief of the farm. The man in charge was a bright young fellow who knew the Indians very well. He treated the delegation kindly, fed and clothed them, and listened to their story. [Illustration: A Bull Sea-Lion at Rest. (_Otaria Jubata._)] [Illustration: Den of Sea-Lions, Staten Island.]