[534] As an example may be quoted the "functions of kinship" described by Dr. Rivers for the Torres Straits Islanders. _Cambridge Exp. to Torres Straits_, v. pp. 144 _sqq._, and vi. pp. 100, 101. Also by Dr. Seligmann for the Melanesians of New Guinea, see passage under this heading in chap. iii. and chap. xxxvii. _op. cit._ [535] Perhaps the best one is given by Dargun, _loc. cit._, pp. 22 _sqq._, where many other opinions are also quoted and criticized. There is also a series of social rules which regulate the social position of the offspring according to that of its parents. This group of rules might appropriately be called _descent_ in the social sense of this word.[536] In the Australian societies, _e. g._ the membership of different social groups--as the local group, the totemic clan, the phratry, the class--is determined by the membership of one of the parents of the given individual. And many authors speak of tribes with paternal and maternal descent. It must be borne in mind, nevertheless, that in order to use the word descent in a definite sense it is always necessary to add what social group is meant. For it is possible that membership in the local group is determined by the father, membership of the phratry by the mother, and membership in the clan by neither of them. The facts of descent do not seem to play a very important rôle and are not suitable to be chosen as the most important feature of kinship. The facts of inheritance also have not very much influence upon kinship (compare below, pp. 290, 291). [536] The word descent is often used without any definition. Mr. E. S. Hartland, _op. cit._, i. p. 258, uses it in a sense synonymous with kinship. Mr. Thomas, too, does not define the meaning of this word, but he uses it more or less in the same way as is done in the text. Compare Thomas, _loc. cit._, pp. 11, 12 _sqq._