Broadcast from Montreal's Expo '67--The Supremes - ""The Happening"" --The Supremes - medley: ""Thoroughly Modern Millie,"" ""Second Hand Rose"" and ""Mame."" (Supremes are wearing flapper costumes.)Other guests: --Xavier Cugat with Charo - Latin medley --Roberta Peters - ""Bell Song"" --Frank Ifield - ""You Came Out Of Nowhere"" & ""She Taught Me How To Yodel"" --Clair & McMahon (comedy team, computer dating routine) --Corbet Monica (comedian) --The Alcettys (balancing act) Audience bows: Jean Drapeau (Montreal mayor); Bill Haughton (harness jockey); Bob Usury (Kentucky Derby winner); Leslie Uggams