The developmental patterns of written and oral syntax were investigated in a group of fourth, sixth, and eighth grade Omaha Indian children living in semipoverty in a rural reservation community. These findings were then compared with the findings of a similar study dealing with white children living in a different cultural, socioeconomic, and geographic area. Concerned primarily with unit lengths and frequency of occurrences of various syntactic structures deriving from sentence-combining transformations at different grade levels, it was predicted that the increased frequency of such transformations would indicate increased linguistic maturity. Analysis of data indicated lower over-all patterns of development for the Indian children than for their white counterparts. The white students also made syntactic gains at rates three to four times greater than the Omaha children. Of particular interest was the tendency of male and female Indian students to show leveling in rates of occurrence of some structures in the eighth grade while white students continued in large gains. (Author/HS)