Aab 67 round angular seeds
From the angular green seeds:—
ab 30 angular green seeds
Thus there were 9 different kinds of seeds produced. There had been separated out at this time 38 individuals like the parent seed plant, AB, and 30 like the parent pollen plant, ab. Since these had come from similar seeds of the preceding generation they may be looked upon as pure at this time. The forms Ab and aB are also constant forms which do not subsequently vary. The remainder are still mixed or hybrid in character. By successive self-fertilizations it is possible gradually to separate out from these the pure types of which they are compounded.
Without going into further detail it may be stated that the offspring of the parent hybrids, having two pairs of differentiating characters, are represented by the series:—
AB Ab aB ab 2ABb 2aBb 2Aab 2ABa 2AaBb
This series is really a combination of the two series:—
A + 2Aa + a
B + 2Bb + b
Mendel even went farther, and used two parent varieties having three differentiating characters, as follows:—