After pondering Harvard's offer for two years, a visiting specialist in medieval literature said yesterday that he has decided to accept a permanent post in the English Department.

Derek Pearsall, who is a visiting professor of English from York University in England, decided this winter to accept the lifetime position which Harvard first offered to him in 1985.

He will continue to split his professorial responsibilities between the University of York and Harvard for two more years, English Department Chairman Joel Porte said.

Pearsall, who is an expert on Chaucer, said that one major factor in his decision to accept the position was the University's "extraordinary" library system which he termed "the best working library" he had ever used.

His appointment, the result of the English Department's international search for a medievalist, comes at a time when Harvard's coverage of the field "has gotten rather thin," Porte said.

With the recent departures of two well-known medievalists to other schools, there are currently three tenured medieval specialists. One of the remaining professors, Lowell Professor of the Humanities William Alfred, is scheduled to retire soon, Porte said.

The History Department is without a tenured medievalist. Last year Lea Professor of Medieval History David M. Herlihy accepted a permanent position at Brown University, and a second tenured medieval historian, Jiles Constable, left Harvard the year before that.

But Pearsall said he is optimistic about the future of medieval studies at Harvard and is confident that a medieval historian will soon be tenured. "That's really quite a gap, and I can't imagine that it could exist for very long," he said.

Visiting Professor of Medieval History Thomas N. Bisson agreed that a permanent appointment in the History department would soon be made. He added that Pearsall's appointment

would be a "great asset to medieval studies at

Harvard since the literature of the middle ages is

at the center of the field."