The earliest phase of sexual relations among primitive men is promiscuity. Following this are five successive stages or forms of marriage and the family, shading into each other, and each running a "long course in the tribes of mankind, with a period of infancy, of maturity, and of decadence."[191] Of these forms the first, second, and fifth are "radical," that is, each developing a distinct system of consanguinity. These systems of consanguinity "resolve themselves into two ultimate forms, fundamentally distinct." One is the _classificatory_ and the other the _descriptive_. "Under the first, consanguinei are never described, but are classified into categories, irrespective of their nearness or remoteness in degree to _Ego_; and the same term of relationship is applied to all the persons in the same category." Under the second, which came in with monogamy and prevails among the Aryan, Semitic, and Uralian peoples, "consanguinei are described either by the primary terms of relationship or a combination of these terms, thus making the relationship of each person specific."[192] The classificatory systems of consanguinity, it should be carefully noted, are more tenacious than the forms of marriage, their nomenclatures often surviving long after the actual relationships they denote have ceased to exist. [191] _Ancient Society_, 389, and on the whole subject, 382-508. In his earlier work, _Systems of Consanguinity_, 480 ff., MR. MORGAN gives fifteen normal stages or institutions in the evolution of marriage and the family. See also the summary in MCLENNAN, _Studies_, I, 251, 252; and LUBBOCK'S elaborate discussion of Morgan, _Origin of Civilization_, 162 ff. [192] _Ancient Society_, 394; _Systems of Consanguinity_, 10-15; LUBBOCK, _op. cit._, 165. The first form of the family in Morgan's series is the consanguine,[193] based on the intermarriage of brothers and sisters, own and collateral, in a group. Though now extinct, this form is thought once to have been universal, rude survivals being found even in the present century among the Hawaiians. But the evidence of its former existence upon which Mr. Morgan relies as conclusive is the Malayan system of consanguinity, which he assumes could only have been produced by it. This system is found among the Maoris, the Hawaiians, and other Polynesians. Anciently it may have prevailed generally in Asia; and it lies at the basis of the Chinese relationships. The Malayan system is classificatory. "The only blood-relationships are the primary," being comprised in five categories. These are parent, child, grandparent, grandchild, brother and sister. Thus consanguine marriage "found mankind at the bottom of the scale" of social progress. [193] _Ancient Society_, 383 ff., 401-23; _Systems of Consanguinity_, 480 ff., 488 ff., where the term "communal family" is used.