This key diagram is part of ''Xtol: Dance of the Ancient Mayan People; Murals from the Temple of the Tigers [Temple of the Jaguar] at Chichen Itza, Yucatan, Mexico,'' a portfolio containing 11 block prints by Octavio Medellin originally published by the Dallas Museum of Fine Arts in 1947. This unnumbered portfolio was signed with a note by Octavio Medellin in 1955. According to ''A Note on the Murals'' by Salvador Toscano, Medellin created the plates from studies he made in 1938 from ''part of a decorated frieze in the interior of the lower chamber or Sanctuary of the Temple of the Tigers [Temple of the Jaguar], adjoining the Ball Court, in Chichen ltza, Yucatan.''