15.64.16  CYCLE 

SET CYCLE [NUMBER=n] [ENTRY[=n]] [WIDTH|INTENSITY=n] [NOCOLOR|WHITE|RED|
          GREEN|BLUE|YELLOW|MAGENTA|CYAN] [NOTEXTURE|SOLID|DOTS|DASHES|
          DAASHES|DOTDASH|PATTERNED|FUNNY|SPACE] [SYMBOL=sym] [PERMANENT]
This  selects  a  cycle  of attributes to be used when the CYCLE option is
used with HISTOGRAM, JOIN, CONTOUR, or PLOT.