HOW CHARACTERS BEHAVE 143 
we deduce that with reference to a single character the total 
offspring resulting from mixed breeding between two races, in 
equal numbers where no selection is involved, will be in the 
proportion of | pure of one variety, } mixed, and } pure of the 
other. This is in the proportion of 25 per cent, 50 per cent, 
and 25 per cent of the total population, or of 1, 2, 1. If the 
proportion between yellow and white had been as 2 to I instead 
of even, then the proportion of the pure and mixed kernels 
would have been different but still definite and easily computed. 
Let us now see what would happen if this crop of pure white, 
pure yellow, and mixed should be planted together again, each 
sort in its true proportion, that is, just as would happen in 
nature, supposing all forms to be equally vigorous and equally 
able to withstand natural selection. We will tabulate this because 
it gets rapidly complicated. In the table let the different combi- 
nations planted be represented by the column headings across 
the top, and the different kinds of pollen produced be repre- 
sented by the headings down the side. 
Remembering that every kind of pollen will fall on every 
kind of silk, and in definite proportions, the results are as follows, 
the body of the table repre- 
senting the various kinds | ¥ aye a 
of progeny and the footing 52. . |] 9 2 ver ae 
at the bottom showing the 27" - | 29%~ | 49%0* 2 yw? 
: nn p2qpj2 2 pau A 
final and total population. * iba ae “ 
In this table the expo- Total, 94 + 4."8c + 6 ye? + 4 yeu8 + vet 
nents represent the num- 
ber of infusions of pure blood ; that is, y pollen on y silk gives 
7 kernels, or two infusions of 7, as compared to the 7 of yw, 
which represents the first mixture of yellow and white, and so 
on for other combinations, 
Now these facts are significant : first, we have all the combi- 
nations possible between y and zw as the result of two admixtures ; 
second, with all this admixture for two generations we still have 
some white (j*) and some yellow (z”) remaining as pure as if 
