I found this at
http://www.virtualstampclub.com/2005_intro.html
"Ten Muppet characters will share a sheet of stamps with a single stamp for their creator, Jim Henson. The Muppets honored include Kermit, Miss Piggy, Fozzie Bear, Sam the Eagle, Statler and Waldorf, Animal, Rowlf the Dog, The Swedish Chef, Dr. Bunsen Honeydew and his assistant Beaker, Camilla the Chicken and Gonzo. Below the single Henson stamp is a larger photo in the sheet's selvage showing Henson in silhouette sitting on the floor, back to a wall, knees drawn up, and talking to Kermit. (Rowlf, by the way, was Henson's original Muppet, 'way back when he got his start on WRC-TV in Washington.)"