'HAIL, HAIL, THE GANG'S ALL HERE': Was one of the tunes played yesterday afternoon by this five-piece Michigan Union "band" as they gave a surprise welcome to a Grand Rapids quartet, made up, left to right, of George C. "Bottles" Thomson, former Michigan varsity fullback who was captain of the team in 1912; Sam Greenawalt, a University of Pennsylvania alumnus; Harold Fletcher, who attended the University literary college from 1916 to 1918, and John Davis Hibbard, a University graduate in mechanical engineering in 1918. Holding the sign behind them is Nicholas Hagerman, a Michigan Union employee who arranged the greeting.