Contents

27 June 1975
Vol 188, Issue 4195

About The Cover

(Upper left) Three hundred-meter telescope, Max Planck Institut fur Radioastronomie, Bonn, Germany; (upper right) 90-foot telescope, Owens Valley Observatory, California Institute of Technology; (center) 120-foot telescope, Vermillion River Observatory, University of Illinois; (lower left) 130-foot telescope, Owens Valley Observatory, California Institute of Technology; and (lower right) 85-foot telescope, Hat Creek Observatory, University of California, Berkeley. See page 1263. [G. W. Swenson, Jr., University of Illinois at Urbana-Champaign, Urbana]