Festus had mud on his sleeve after Ms. Royce, who had fallen in the mud, grabs his sleeve. The mud is gone after the scene never to be seen again.
Barry Atwater (1918-78) was an amazing and underrated actor. This was his fifth and last appearance on Gunsmoke. He is best known for his role as the vampire on the TV film, The Night Stalker (1972), but he appeared in many other roles, including guest roles on the series, Twilight Zone, Star Trek, Perry Mason, Have Gun - Will Travel, Kung Fu, Boanza, Night Gallery, and Rockford Files.