Both parents originally had this genotype: (Ee, Tt). The parents are known as “dihybrids” because they each have 2 hybrid genes. When dihybrids make gametes, they produce 4 possibilities which are listed on top and on the side of the box below.
E = Two Eyes, ee = one eye
T = Triangular Head, tt = pentagonal head
The following phrase may also help you determine the gametes of a dihybrid:
BIG ŕ BIG
BIG ŕ small
small ŕ BIG
small ŕ small