THE NUER OF THE SOUTHERN. SUDAN 277
higher to the west of the Nile. Nowhere is there a high degree of local concentration.
Although dry-season movement produces more social interrelations between members of different tribal sections than the rainy season distribution might lead us to expect, these contacts are mainly individual or, when they concern groups, only smaller
DIAGRAM No. I
local communities, and not the larger tribal sections, are brought into association. This is probably one of the reasons for the lack of structural complexity and of great variation of types of social relations among the Nuer. Outside small kinship groups and village and camp communities, there are no co-operative economic combinations and there are no organized ritual associations. Except for occasional military ventures, active corporate life is restricted to small tribal segments.