becomes certain when we find the cross-cousin marriage still persisting in many parts of South India, and that among one such people at least, the Todas,[1] this form of marriage is associated with a system of relationship agreeing both in its structure and linguistic character with that of the Tamils. I have elsewhere[2] brought together the evidence for the former prevalence of this form of marriage in India, but even if there were no evidence, the terminology of relationship is so exactly such as would follow from the cross-cousin marriage that we can be certain that this form of marriage was once the habitual custom of the people of South India.
While South India thus provides a good example of a case in which we can confidently infer the former existence of the cross-cousin marriage from the terminology of relationship, the evidence from North America is of a kind which gives to such an inference only a certain degree of probability. In this case it is necessary to suspend judgment and await further evidence before coming to a positive conclusion.
I will begin with a very doubtful feature which comes from an Athapascan tribe, the Red Knives[3] (probably that now called Yellow Knife). These people use a common term, set-so, for the father's sister, the mother's brother's wife, the wife's