We saw in Chapter 6 that the principal difference between the Karadjeri and Forrest River systems and the Kariera–like systems discussed in Chapters 4 and 5 is that the former have an additional equivalence rule, a rule of structural equivalence between agnatically related kin of alternate generations (the AGA rule). This, however, is a low–order rule superimposed on systems that are, aside from the consequences of this rule, quite similar to Kariera–like systems in general. The most notable consequences of the AGA rule, when subordinate to the other equivalence rules that characterize Kariera–like systems in general, is that the potential male parallel–grandparent class becomes a subclass, either covert or overt, of the SIBLING class; and the potential cousin (that is, cross–cousin) class becomes a subclass, again either covert or overt, of the CROSS–GRANDKIN class. Many Australian systems of kin classification share these features of the Karadjeri and Forrest River systems but add to them, again as a low–order rule, the rule of structural equivalence between uterine kin of alternate generations. One consequence of this is that the potential female parallel-grandparent class also becomes a subclass of the SIBLING class.

The Arabana system has this feature, and so do the Murawari and Wongaibon systems described by Radcliffe-Brown (1923) as “less than fully developed” Aranda–type systems. Because the Arabana data are superior, this chapter focuses on that system and concludes with some brief comments on the Murawari and Wongaibon systems.