No Dave Ebersole? Hmm... guess it's up to me.
#19 Vincent Price - House of Horror sketch & finale
#21 Twiggy - Phantom of the Muppet Show in the plot
#22 Ethel Merman - Broadway Medley (You're Just In Love)
#31 Edgar Bergen - sings in Consider Yourself
#36 Bernadette Peters - sings Sheik of Araby
#41 Julie Andrews - cameo in finale
#52 Gilda Radner - in Muppet Melodrama
#64 Jean Stapleton - in Muppet Melodrama
I thought that was all...