The Nathan M. Pusey Library--tucked between Widener and Lamont libraries and recently landscaped for today's ceremonies--is expected to open on time and within its budget.

The building, begun the day after Commencement two years ago, will connect Lamont, Widener and Houghton libraries when opened to students in January. The official opening will occur either in late Spring or early Fall 1976.

Small Cost Overrun

Financial Vice President Hale Champion said yesterday the library construction cost will run only slightly over its budget--"maybe $30,000 over" an $8-million budget--despite rampant inflation and a two-month ironworker strike in 1974.

Richard G. Leahy, associate dean of the Faculty for resources and planning, said yesterday that a construction strike has delayed finishing the roof of the library but that the strike will probably not affect the building's mid-winter opening. He added that the official opening will come later to allow for "finishing touches" and better weather.

President Emeritus Nathan M. Pusey '28, who said yesterday he is too busy in New York City to attend today's Commencement, was in Cambridge several weeks ago for the dedication of the Lamont Bench in the Yard and toured the library then.

He said yesterday he thought what he saw of the building struck him as "fine" and that he is cager to see the finished project.

Late last fall, Dean Rosovsky said the Faculty might delay opening the Pusey Library because the Faculty did not have the funds to pay for the library's operating costs.

Louis E. Martin, librarian of Harvard College, was unavailable for comment yesterday.