The Trustees of Vassar College voted yesterday to reject the proposed merger of Vassar with Yale because, as one Trustee said, of "our desire to be mistress in our own house."

Their decision that "the college should remain in its place" overruled the recommendation of the Yale-Vassar Study Group, which in September advocated a merger between the two colleges.

However, Vassar's decision does not rule out coeducation at the two institutions. Both Yale and Vassar are planning to establish coordinate colleges near their present sites.

Isolation Is Out

Recognizing that "education of undergraduate women in isolation from men has outlived its historic justification in terms of Vassar," the Trustees said that a "coordinate men's college in Pough-keepsie" was being considered.

Kingman J. Brewster, President of Yale University, sketched plans yesterday for a $50 to $80 million women's coordinate college for New Haven.

Brewster Disappointed

Although "disappointed" over Vassar's decision, Brewster did not feel that the joint study was in vain. "The thinking and development by the joint committee has brought us much nearer to the goal of a first-rate college for women in New Haven," he said at yesterday's press conference.

Brewster envisions no Harvard-Radcliffe relationship between Yale and its women's counterpart. The feminine side of Yale will have an independent curriculum, its own faculty, degrees, and "identity," with the possibility of considerable cross-registration with Yale.

Now deprived of dreams of New Haven, Vassar is considering a small graduate school for "interdisciplinary" studies, and $50-75 million institute for Vassar field work in New York City.

The members of the Yale-Vassar Group also voiced their disappointment yesterday. Eve Katz, assistant professor of French at Yale, and executive secretary of the group, said yesterday, "It is comforting to know that this does not mean the end of an undergraduate women's college at Yale, but it is a regrettable way to start."

Alumnae Glad

Clyde Griffin, teacher of History at Vassar, said "I'm sorry. In my personal opinion, though, the majority of the faculty and alumnae are glad."

Griffin said that he had sensed what the decision would be before it was announced. "The announcement came as a surprise only because I wasn't told of it before hand," he said.