When Dally and Ponyboy go to the movies, they sit down in the rows of seats near the concession stand right behind two girls. Dally starts saying terrible things just to see what happens and Ponyboy describes the two of them. They were “tuff-looking… dressed sharp and really good-looking.” He suspects that they are around sixteen or seventeen.
Pony describes Marcia as having “short dark hair.” Later on he points out that she is a bit smaller than Cherry. She is also the one who recognizes Dally and says that he rides for the “Slash J” sometimes at the rodeo.
Besides her physical appearance she also seems to be a bit less proper and spirited than Cherry. Marcia gets along really well with Two-bit.