OF THE BUREAU OF ETHNOLOGY. XLV 



IV. — The son of a member of a brother-group calls each one 

 of the group, father; the father of a member of a brother-group 

 calls each one of the group, son. Thus a father-group is coex- 

 tensive with the brother-group to which the father belongs. A 

 brother-group may also constitute a father-group and grand- 

 father-group, a son-group and a grandson-group. It may also 

 be a patruate-group and an avunculate-group. It may also be 

 a patruate cousin-group and an avunculate cousin-group; and 

 in general, every member of a brother-group has the same 

 consanguineal relation to persons outside of the group as that 

 of every other member. 



The principles enunciated above may be stated in another 

 way, namely: A kinship body is divided into brother-groups 

 and sister-groups, and group is related to group lineally and 

 collaterally; and every group bears a distinct relationship to 

 every other group. 



It will thus be seen that the brother-group and the sister- 

 group constitute the fundamental units of tribal society. 



A tribe may be defined as follows: A tribe is a congeries 

 of brother-groups and sister-groups, and every group recog- 

 nizes a distinct correlative consanguineal kinship with every 

 other group; and series of groups are related to series of groups 

 by the ties of affinity, i.e., marriage; to explain which necessi- 

 tates the consideration of the clan. 



