Senator Joseph R. McCarthy (R-Wis.) said yesterday he believed there should be a "full-scale investigation of alleged communism in colleges and universities." His announcement contradicted reports that he might shift his investigations from the issue of communism.

He cited Presirent Pusey and the University for refusing to fire teachers who "hide behind the Fifth Amendment." He said colleges are unable to weed out their own subversives, claiming this as a good reason for continued investigation by Congress.

Reports in at least five major newspapers had said that the Eisenhower administration has been urging McCarthy to turn his efforts chiefly to the investigation of waste and corruption--letting other congressional groups carry on the task of exposing subversives.

When asked yesterday about the truth of these reports, McCarthy said, "I've made no deals."