President Pusey has been subpoenaed to appear at the Oct. 30 trial of Cheyney C. Ryan, an ex-student who is charged with criminal trespass for allegedly appearing on campus in two demonstrations during the national student strike last May.

Ryan, a former SDS co-chairman who was severed from Harvard for his part in an obstructive demonstration last November, faces a two-month prison term and a $200 fine.

The subpoena-served yesterday morning by Phillip DeSimone, a second year graduate student, and witnessed by Richard A. McCray, assistant professor of Astronomy-directs Pusey to appear in the Third District Court of Middlesex County with "records, papers, and documents relating to the ouster of [Cheyney Ryan] from Harvard University and his eviction from those premises."

It is not clear, however, that Pusey will answer the summons. Daniel Steiner '54, general counsel to the University, who is advising Pusey on the matter, said yesterday afternoon that no decision had yet been reached.

If Pusey should refuse to obey the subpoena-which is notarized by a member of the Massachusetts bar-the defense will charge him with contempt of court, Ryan said yesterday.

Other representatives of the defense will deliver subpoenas today or Friday to Deans Dunlop and May and Archibald Cox, the administration's crisis manager. Dunlop and May had no comment last night and Cox could not be reached.

Ryan was suspended from Harvard following a sit-in in May's office which demanded that the University immediately promote all painter's helpers to full painter status. The helpers were later made apprentices and placed in a training program under which they could become full painters within three years.

At the time of the punishment, Harvard warned Ryan that he would be legally prosecuted if he appeared anywhere on campus. According to University officials, students required to leave the University for any reason are told not to be on campus during their period of absence.

Ryan, who said he will conduct his own defense in court, expressed doubt that Pusey or the other officials would answer the subpoenas. "I don't think they have the nerve to show up in front of students where they have to swear to tell the truth," he said.

Warrants were issued for the arrest of three other ex-students on similar charges last July. So far, none of the other former students have been arrested.