In Virginia, the state college system has used only 75 percent of the scholarships the legislature funded to recruit black students to local universities. In Florida, despite a commitment the state made to the federal government to increase the rate of blacks entering its colleges, the number of black students has dropped.

And after almost 12 years of legal struggle to prod the federal government to eradicate racial discrimination in southern schools and colleges, lawyers for the NAACP Legal Defense Fund are back in court.

They accuse several states of backsliding, blame the government for failing to enforce their plans to end segregation and have asked the judge to force compliance.

The suit, originally Adams vs. Richardson and several administrations later now Adams vs. Bell, has become a case study on how a lawsuit can drive the federal government. It was filed in the fall of 1970, when civil rights groups felt the Nixon administration was ignoring racial discrimination in southern schools and colleges.

NAACP lawyers have returned to court periodically to keep the pressure on.

The latest brief charges that the government has ignored standards it developed, under court order, to measure the influx of blacks in the affected states' college systems.

The dispute centers on whether the standards, called "criteria," are flexible guidelines, as the government has claimed, or are requirements mandated by the court order, as the NAACP contends.

U.S. District Court Judge John H. Pratt, who has overseen the case since the beginning, first ruled a decade ago that the federal government had to negotiate settlements with 10 states or, failing that, coerce compliance.

The Department of Health, Education and Welfare negotiated agreements in 1974 with Arkansas, Florida, Georgia, Maryland, North Carolina, Oklahoma, Pennsylvania and Virginia.

After negotiations failed with Louisiana and Mississippi, HEW referred those cases to the Justice Department, which filed suit. The Reagan administration reached a settlement with Louisiana last year and is in negotiations now with Mississippi.

In 1975, the NAACP defense fund lawyers told Pratt, as they have just done again, that the negotiated plans were not satisfactory.

The next year he ordered several plans revoked and told HEW to come up with some "criteria" to measure progress.

The government approved several state plans again after the criteria set goals in such as erasing disparities between white and black enrollments, increasing black graduation rates and boosting the numbers of black staff and faculty members.

A few weeks ago, the NAACP lawyers went back to Pratt, arguing the state efforts still are not enough. The Reagan administration, they told the judge, is ignoring the problem.

State officials respond that the criteria were not fair in the first place. It is hard to measure progress, they say, because students cannot be forced to attend state colleges. They are not assigned, as they are to high schools.

Jean Fairfax of the NAACP defense fund's New York office, counters that it is up to the state systems to remedy past abuses by recruitment, whatever the difficulties.

Barry Dorsey, associate director of Virginia's commission on higher education, acknowledged that the state has awarded only 1,522 of some 2,000 scholarships the legislature authorized.

But he said it is getting harder to recruit from a dwindling pool of college-age youngsters. And he added, "The state gets no credit for the students who go out of state or to private schools."

The numbers of blacks entering and staying in the state's college system compare poorly to those of whites, Dorsey said, because black students often are not encouraged to take college preparatory courses in high school.

The state is working on the problem, he said, by emphasizing the importance of such courses to black parents and high school counselors.

In another example cited in the defense fund brief, black enrollment in the Florida state college system has dropped in the past few years. There also was a 27 percent drop in black graduate students between 1977 and 1980.

And Fairfax noted that Miami-Dade Junior College lost 43 percent of its black enrollment in the same span, apparently because of increased admission standards.

Leaders of the traditionally black colleges view the dispute over the "criteria" with mixed emotions. They like the plans to pour more money into their schools, but shy from attempts fully to integrate them, saying too many white students would harm the character of the institutions.

The court filing notes, for example, that the numbers of white students at Virginia State University and Norfolk State College have dropped in the past few years, despite state promises to increase them.

Samuel Myers, executive director of the National Association for Equal Opportunity in Higher Education, a black college umbrella group, said his group approves of the increased funding for black schools the Reagan administration emphasized in settling the North Carolina college desegregation case last summer.

But he added that the figures showing declines in black enrollments in other states is discouraging. "We're sympathetic in challenging that," Myers said.