if a man saw a carved boomerang which he desired to have, he would say to the owner, "I will give you such and such things for it, if you will be my Yutchin." If this is agreed to, and the proposer after having been away at some outside place brings back the things agreed upon, the exchange is made.
When the Dieri see a man or a woman with a string round his or her neck, they say, "Who are you Yutchin for?"
A son may be a Yutchin for his father; for instance, the latter may promise to make some boomerangs for his sons while they are out hunting for him. Whatever they catch, no matter how much it is, they hand it to him on their return; and the women flock to see what kind of Yutchin the boys have been. The boomerangs are of course made and handed over at once. Little boys will coax their father to make boomerangs for them by promising to be his Yutchin.
When at Cooper's Creek I observed that the blacks used shields made of some wood not known to me in that part of Australia. Subsequently, when I was able to obtain information from them, I learned the following particulars. The Yantruwunta obtained these shields from their neighbours higher up Cooper's Creek, who got them from tribes farther to the north-east. The Yantruwunta on their part exchanged weapons made by them, and stone slabs for grinding seeds which they brought from the south. I also saw among these tribes, though rarely, a portion of a large univalve shell, worn suspended by a string from the neck, which I was told came from the north. Inquiries made later from the Dieri show that they bartered with the Mardala, or hill tribes, to the .south of them, for skins.
This information indicates an extensive system of inter-tribal communication and barter, which was apparently carried on by men who were the recognised means of communication. But there are also established trade centres at which the tribes meet on certain occasions for a regulated barter. One of these old trade centres is Kopperamana on the Cooper, where the surrounding tribes met periodically
- S. Gason.