#29  Since each F1 is  Heterozygous (H Y B R I D) for two traits. it is referred to
             as being a D I (prefix for two) H Y B R I D  (heterozygous).   The results of the
             F1 x F1 mating is known in biology as the  D I H Y B R I D   CROSS.  It is
             tricky to analyze, but we now have the visible graphic to help us.