S0< l M- ORG wi/a ["ION 89 



by language and blood. Our previous list of tribes, 

 therefore, embraces groups, all subdivisions of which 

 have approximately equal cultural values for the whole 

 series of traits (p. 19). 



Using the term, tribe, to designate units with in- 

 dependent governing bodies, we find that these tribes are 

 in turn composed of small units, each under the leader- 

 ship of a chief, seconded by a few head men. These sub- 

 divisions are often designated in technical literature as 

 bands — a chief and his followers. It frequently happens 

 that the members of these bands inherit their member- 

 ships according to a fixed system. When this is reckoned 

 through the mother, or in the female line, the term clan 

 is used instead of band; when reckoned in the male 

 line, gens. The clans and gentes of the Plains are of 

 special interest because of the tendency to regulate 

 marriage so that it must be exogamic, or between 

 individuals from different clans and gentes, and also 

 because of the difficulty in discovering whether this is 

 due to the mere accident of blood relationship or some 

 other obscure tendency. On this point, there is a large 

 body of special literature. 



An exogamic gentile system has been reported for 

 the Omaha, Ponca, Iowa, Oto, Missouri, Osage, and 

 Kansas. An exogamic clan system prevails among the 

 Hidatsa, Crow, and the Mandan. Among the Plateau 

 group, the Arapaho, Kiowa, Comanche, and probably 

 also among the Dakota and Plains-Cree we have only 

 bands without marriage restrictions. In addition, we 

 have some problematical cases in the Blackfoot, Gros 



