The fact that all the tribes of the Cape Horn region build such wretched houses has always been taken as a proof of their lack of intelligence. How great a mistake was thus made in the case of the Yahgans has already been shown. The Onas, as will some day be learned, are also misjudged. The reason for building so frail a shelter is apparent on a brief consideration of their method of life. They are necessarily nomads. When the food of one spot was eaten they had to migrate. Now, the Onas had no horses or beasts of burden, as did the Tehuelches. They could not carry big skin tents about as the Tehuelches did. So they built a temporary shelter only. In the coldest weather a location near the seashore, where mussels and fish abounded, was usually chosen, and there they built larger and better wigwams. When they migrated to Patagonia and acquired horses they made skin tents. They did not make poor shelters from any lack of intelligence. The skin of the Ona is remarkably white for one who lives all but naked in the open air. Their hair is black, but lustreless, and they have a curious habit of singeing off the hair so as to leave a tonsure on top of the head just where the North American Indian allowed the hair to grow long for a scalp lock. The face is oval, the eyes dark and pleasant, the cheek bones not too prominent, the nose sometimes quite prominent, and the mouth full and with regular but yellowish teeth. Because whiskers come late in life, and so are an indication of coming age, the men pluck them out, through a desire to appear young; but after thirty-five they let the beard grow because of the pain of pulling so many hairs as then come. They are remarkable for using combs made of whalebone. No other tribe near Cape Horn does that. Their shoulders are broad and strong and the chests deep. The mothers have hanging breasts, but those of the maidens are well-rounded and firm. The arms and limbs are round and sinewy, but the stomach, especially after a square meal, is very prominent. Of the capacity of the Ona's stomach, one story will serve. A girl of about fifteen, who was captured on a northern ranch, refused to eat for eight days, and then appetite got the better of her temper. A sheep had been roasted whole for the dinner of the rancher's family, but the Ona girl was allowed to begin on it, and seeing that her appetite was good, she was not interrupted. When she had finished, so they say, she had cleaned all the bones of the sheep. For making a fire the Onas carry bits of iron ore, which come from an island in the Alaculoof region, west of Tierra del Fuego, and are obtained by barter with that tribe. Flints and agates abound in the Ona country, and these with the ore and a bit of dry fungus, always carried wrapped in a bit of hide or a bladder, enable the Ona to light a fire even in a rain-storm.