Mendel's principles of heredity: A defence

by William Bateson; Gregor Mendel

Pollen cells

AB + AB + AB + AB + Ab + Ab + Ab + Ab +

aB + aB + aB + aB + ab + ab + ab + ab.

Egg cells

AB + AB + AB + AB + Ab + Ab + Ab + Ab +

aB + aB + aB + aB + ab + ab + ab + ab.

In the process of fertilisation each pollen form unites on an average equally often with each egg cell form, so that each of the four pollen cells AB unites once with one of the forms of egg cell AB, Ab, aB, ab. In precisely the same way the rest of the pollen cells of the forms Ab, aB, ab unite with all the other egg cells. We obtain therefore—

AB/AB + AB/Ab + AB/aB + AB/ab + Ab/AB + Ab/Ab + Ab/aB + Ab/ab +
aB/AB + aB/Ab + aB/aB + aB/ab + ab/AB + ab/Ab + ab/aB + ab/ab,

or

AB + ABb + AaB + AaBb + ABb + Ab + AaBb + Aab +
AaB + AaBb + aB + aBb + AaBb + Aab + aBb + ab = AB +
Ab + aB + ab + 2ABb + 2aBb + 2AaB + 2Aab + 4AaBb[42].