[403] SPENCER, _Principles of Sociology_, I, 679-81, 748 ff., 750. See, however, the criticism of STARCKE, _op. cit._, 151-53, 159 ff.; and compare WESTERMARCK, _op. cit._, 510 ff.; MCLENNAN, _Studies_, I, 108 ff.; _Fortnightly Review_ (1877), 701; and SPENCER'S "Short Rejoinder," _ibid._, 897. But elsewhere Spencer thinks the levirate may arise in the duty of caring for the brother's children--a general cause of polygyny: _op. cit._, 691, 692. For examples of inheritance of widows, see KOHLER, "Das Recht der Azteken," _ZVR._, XI, 54; "Das Negerrecht, namentlich in Kamerun," _ibid._, XI, 416, 423; and for widower inheritance among the Chins, _idem_, _ibid._, 186 ff. [404] STARCKE, _op. cit._, 141 ff. For his theory of juridical fatherhood see _ibid._, 121-27, 135, 139; and compare the similar view of WAKE, _Marriage and Kinship_, 78 ff. This author gives an interesting discussion of the case of Boaz and Ruth, _op. cit._, 172-78, which may be compared with MCLENNAN, _Studies_, I, 109 n. 3. On the evidence for juridical fatherhood among the Arabs, consult SMITH, _Kinship and Marriage_, 119, 120. Again, not only is the general extent of polyandry limited, but even where it exists it is confined in almost every case "to a very small part of the population."[405] It is sometimes restricted to the poorer classes, sometimes to the rich; and nearly always it is found side by side with polygyny or monogamy. There is another limitation, already noticed, which tells very strongly against the theory of its origin in promiscuity. Polyandry usually shows a tendency in the direction of monogamy. Sometimes each of the husbands lives with the wife during a certain period, while the others are absent; or frequently, "as one, usually the first married, wife in polygynous families is the chief wife;" so also, "one, usually the first, husband in polyandrous families is the chief husband." In him authority and the property are vested, and all the children, even, are feigned to be his.[406] [405] WESTERMARCK, _op. cit._, 455-57. [406] _Ibid._, 457-59, 113-17; _cf._ especially STARCKE, _op. cit._, 135. HELLWALD, _Die mensch. Familie_, 264 ff., gives many interesting details.