Women's rights groups, civil libertarians and a member of the venerable all-male Cosmos Club told a D.C. Council committee yesterday that rules barring women from membership in private clubs that serve public functions are discriminatory and should not be tolerated in the District.

The committee is considering a bill that would force all-male clubs that have more than 350 members and regularly serve meals to nonmember guests to admit women members.

Mayor Marion Barry has indicated he supports the bill, which was introduced by council member Jim Nathanson (D-Ward 3). Similar legislation has won recent approval in Los Angeles and New York.

Nathanson said that such institutions are not "distinctly private," and therefore must abide by the D.C. human rights statute that forbids discrimination on a number of grounds, including sex.

"A major barrier to full equal opportunity in the professions is the discriminatory practice of certain membership organizations where business deals are often made," said Nathanson.

The legislation, Nathanson said, is likely to affect only a handful of clubs, chief among them the Cosmos Club, located in an Embassy Row mansion, and the 124-year-old Metropolitan Club. The Cosmos Club has more than 3,000 members; the Metropolitan more than 2,000. Both limit membership to men of achievement, including scholars and government officials.

Peter Ehrenhaft, a local lawyer and Cosmos Club member, said he has fought the males-only policy for seven years and called the club's rule "anachronistic."

"It is not fair that women should be excluded from organizations that they and many men perceive as significant to their professional and personal lives but from which they are barred for no reason other than by the accident of their births as females," said Ehrenhaft.

Opposition to the Nathanson proposal came from the Conference of Private Organizations and Elaine Dym, who testified for the "Ad Hoc Committee of Cosmos Wives."

"You should know that there are many women, some highly placed professionals, who have no desire to become members of private men's clubs," Dym said. "We have our women's organizations and do not want to include male members in those."

Dym said that Nathanson's bill brings to mind "a vision of an Orwellian future -- a totalitarian society in which we will be asked what we are doing and whom we have invited into our homes."

Gerard Hurley, the executive director of the private clubs' group, said that the thrust of the proposed legislation is "changing the essence of private status."

If the measure becomes law, organizations found to be in violation could be taken to court by the D.C. Office of Human Rights and ultimately could face revocation of other city-granted permits such as liquor licenses.

Several of those testifying in favor of the bill likened it to the struggle during the civil rights movement to extend public accommodations laws to include black people.

Ann F. Lewis, representing the local chapter of Americans for Democratic Action, held up an enlarged copy of the Cosmos Club's bylaws, saying that they "make a mockery of civil rights.