The Department of Education said yesterday that Missouri, Kentucky and Texas "still bear the vestiges of unconstitutional segregation" in their state-supported higher education systems.

Missouri and Kentucky were notified of the findings and given 60 days to develop corrective plans, but Texas averted formal citation when state Attorney General Mark White submitted a voluntary desegregation plan Wednesday.

Action on the three states followed lengthy investigations. The department did not allege they are excluding blacks or other minorities from state colleges and universities or actively practicing segregation. Rather, it said, they had failed to act swiftly enough to integrate the separate white and black systems that had been established when segregation was legal.

In Missouri, DOE said, the state had made "significant progress" in integrating the separate higher education systems since the Supreme Court outlawed segregation in 1954. However, the state flagship institution, the University of Missouri at Columbia, had only 3.3 percent black enrollment in 1978, and another UM branch, at Rolla, had only 3.8 percent, and Southeast Missouri State only 3.3 percent, thus maintaining these institutions as essentially all-white, the department said.

In Kentucky, the department said, progress also had been made in integrating former separate institutions. But four tradionally white colleges still have 92 percent white enrollment, while traditionally black Kentucky State University is still 82 percent black.