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[22] (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 mother and the husband’s mother, a usage which would be the necessary result of the cross-cousin marriage. Against this, however, is to be put the fact that there are three different terms for the corresponding male relatives, the two kinds of father-in-law being called _seth-a_, the mother’s brother _ser-a_, and the father’s sister’s husband _sel-the-ne_. Further, the term _set-so_, the common use of which for the aunt and mother-in-law seems to indicate the cross-cousin marriage, is also applied by a man to his brother’s wife and his wife’s sister, features which cannot possibly be the result of this form of marriage. These features show, either that the terminology has arisen in some other way, or that there has been some additional social factor in operation which has greatly modified a nomenclature derived from the cross-cousin marriage. [22] See Morgan, _Systems ..._, Table II. A stronger case is presented by the terminology of three branches of the Cree tribe, also recorded by Morgan. In all three systems, one term, _ne-sis_ or _nee-sis_, is used for the mother’s brother, the father’s sister’s husband, the wife’s father and the husband’s father; while the term _nis-si-goos_ applies to the father’s sister, the mother’s brother’s wife and the two kinds of mother-in-law. These usages are exactly such as would follow from the cross-cousin marriage. The terms for the sister’s son of a man and the brother’s son of a woman, however, differ from those used for the son-in-law, and there is also no correspondence between the terms for cross-cousin and any kind of brother- or sister-in-law. The case points more definitely to the cross-cousin marriage than in the case of the Red Knives, but yet lacks the completeness which would allow us to make the inference with confidence. The Assiniboin have a common term, _me-toh-we_, used for the father’s sister, the mother’s brother’s wife and the two kinds of mother-in-law, and also a common term, _me-nake-she_, for the mother’s brother and the father’s sister’s husband, but the latter differs from the word, _me-to-ga-she_, used for the father of husband or wife. The case here is decidedly stronger than among the Red Knives, but is less complete than among the Crees.