ABSTRACT
Earlier in this book, in the accounts of the parish and of the age-group, some emphasis was given to the fact that both of these groups are segmented dichotomously, and both are themselves bisections of larger units. In the present part of the book it has been noted that an autonomous family and both types of patrilineages are normally divisible into two complementary parts, although, deliberately, little attention was given to this feature. In all these groups this kind of bifurcate segmentation exemplifies a principle of social structure which is pervasive in Arusha society, and is essential to regular social processes. It is now necessary to give it detailed consideration as it operates in the patrilineal system.
