institutions.

I am able to carry out this task more fully than has hitherto been possible because I have collected in Melanesia a number of systems of relationship which differ far more widely from one another than those recorded in Morgan’s book or others which have been collected since. Some of the features which characterise these Melanesian systems will be wholly new to ethnologists, not having yet been recorded elsewhere, but I propose to begin with a long familiar mode of terminology which accompanies that widely distributed custom known as the cross-cousin marriage. In the more frequent form of this marriage a man marries the daughter either of his mother’s brother or of his father’s sister; more rarely his choice is limited to one of these relatives.

Such a marriage will have certain definite consequences. Let us take a case in which a man marries the daughter of his mother’s brother, as is represented in the following diagram:

Diagram 1[8]

One consequence of the marriage between C and d will be that A, who before the marriage of C was only his mother’s brother, now becomes also his wife’s father, while b, who before the marriage was the mother’s brother’s wife of C, now becomes his wife’s mother. Reciprocally, C, who before his marriage had been the sister’s son of A and the husband’s sister’s son of b, now becomes their son-in-law. Further, E and f, the other children of A and b, who before the marriage had been only the cousins of C, now become his wife’s brother and sister.

Similarly, a, who before the marriage of d was her father’s sister, now becomes also her husband’s mother, and B, her father’s sister’s husband, comes to stand in the relation of husband’s father; if C should have any brothers and sisters, these cousins now become her brothers- and sisters-in-law.

The combinations of relationship which follow from the marriage of a man with the daughter of his mother’s brother thus differ for a man and a woman, but if, as is usual, a man may marry the daughter either of his mother’s brother or of his father’s sister, these combinations of relationship will hold good for both men and women.

Another and more remote consequence of the cross-cousin marriage, if this become an established institution, is that the relationships of mother’s brother and father’s sister’s husband will come to be combined in one and the same person, and that there will be a similar combination of the relationships of father’s sister and mother’s brother’s wife. If the cross-cousin marriage be the habitual custom, B and b in Diagram 1 will be brother and sister; in consequence A will be at once the mother’s brother and the father’s sister’s husband of C, while b will be both his father’s sister and his mother’s brother’s wife. Since, however, the mother’s brother is also the father-in-law, and the father’s sister the mother-in-law, three different relationships will be combined in each case. Through the cross-cousin marriage the relationships of mother’s brother, father’s sister’s husband and father-in-law will be combined in one and the same person, and the relationships of father’s sister, mother’s brother’s wife and mother-in-law will be similarly combined.

In many places where we know the cross-cousin marriage to be an established institution, we find just those common designations which I have just described. Thus, in the Mbau dialect of Fiji the word vungo is applied to the mother’s brother, the husband of the father’s sister and the father-in-law. The word nganei is used for the father’s sister, the mother’s brother’s wife and the mother-in-law. The term tavale is used by a man for the son of the mother’s brother or of the father’s sister as well as for the wife’s brother and the sister’s husband. Ndavola is used not only for the child of the mother’s brother or father’s sister when differing in sex from the speaker, but this word is also used by a man for his wife’s sister and his brother’s wife, and by a woman for her husband’s brother and her sister’s husband. Every one of these details of the Mbau system is the direct and inevitable consequence of the cross-cousin marriage, if it become an established and habitual practice.

This Fijian system does not stand alone in Melanesia. In the southern islands of the New Hebrides, in Tanna, Eromanga, Anaiteum and Aniwa, the cross-cousin marriage is practised and their systems of relationship have features similar to those of Fiji. Thus, in Anaiteum the word matak applies to the mother’s brother, the father’s sister’s husband and the father-in-law, while the word engak used for the cross-cousin is not only used for the wife’s sister and the brother’s wife, but also for the wife herself.

Again, in the island of Guadalcanar in the Solomons the system of relationship is just such as would result from the cross-cousin marriage. One term, nia, is used for the mother’s brother and the wife’s father, and probably also for the father’s sister’s husband and the husband’s father, though my stay in the island was not long enough to enable me to collect sufficient genealogical material to demonstrate these points completely. Similarly, tarunga includes in its connotation the father’s sister, the mother’s brother’s wife and the wife’s mother, and probably also the husband’s mother, while the word iva is used for both cross-cousins and brothers- and sisters-in-law. Corresponding to this terminology there seemed to be no doubt that it was the custom for a man to marry the daughter of his mother’s brother or his father’s sister, though I was not able to demonstrate this form of marriage genealogically.

These three regions, Fiji, the southern New Hebrides and Guadalcanar, are the only parts of Melanesia included in my survey where I found the practice of the cross-cousin marriage, and in all three regions the systems of relationship are just such as would follow from this form of marriage.

Let us now turn to inquire how far it is possible to explain these features of Melanesian systems of relationship by psychological similarity. If it were not for the cross-cousin marriage, what can there be to give the mother’s brother a greater psychological similarity to the father-in-law than the father’s brother, or the father’s sister a greater similarity to the mother-in-law than the mother’s sister? Why should it be two special kinds of cousin who are classed with two special kinds of brother- and sister-in-law or with the husband or wife? Once granted the presence of the cross-cousin marriage, and there are psychological similarities certainly, though even here the matter is not quite straightforward from the point of view of the believer in their importance, for we have to do not merely with the similarity of two relatives, but with their identity, with the combination of two or more relationships in one and the same person. Even if we put this on one side, however, it remains to ask how it is possible to say that terms of relationship do not reflect sociology, if such psychological