7 * 
The Inheritance of PeJoria in Foxgloves. 
The result of selfing plant D,—13 white, 1 magenta,—indicates 
that it is heterozygous for magenta colour-factor, i.e., is Mm. So 
that its full gametic composition with respect to ground colour is 
Ww Mm, and the gametes which it produces bear the characters 
WM, Wm, wM, wm. 
Male gametes bearing these characters meeting female gametes 
also bearing these characters will produce zygotes, the composition 
of which may be indicated in the usual way (Fig. 2). 
wn 
W ** 
ur FI 
tv*m 
W M 
WM 
WIM 
WM 
Ww 
WM. 
wM 
WM 
lu- t*l 
WM 
Wm 
w* 
Wm 
Wm 
Cr in 
\a|w 
vj-in 
ur 
Wm 
urM 
WM 
u- in 
>n 
WM 
Ur 1W 
Wm 
V*1»\ 
jggf 
Wrm 
v-»*> 
Fig. 2. 
Illustrating the Ratio of 13 White : 3 Magenta (shaded) in F, of Plant D, 
selfed (see Text). 
Of 16 zygotes, 12 will produce white flowers because of the 
presence of the dominant white factor (W), 1 because of the absence 
of both magenta colour-factor and dominant white factor (wm). 
That is we shall expect a ratio of 13 white to 3 magenta. The 
numbers obtained in Fj from plant D selfed are 13 whites, 1 
magenta, and though it must of course be conceded that the 
number of F t plants raised is too small to provide absolute proof, 
yet the fairly close agreement of the numbers obtained (13 white, 
1 magenta) with the numbers expected (13 white, 3 magenta) 
justifies the assumption that plant D is heterozygous for both the 
dominant-white and the magenta-colour factors. 
As we shall show, the hypothesis that plant D is heterozygous 
for these factors permits of a reasonable interpretation of the 
results of other crosses. 
Thus plant E, white with yellow spots, when selfed, gives an 
F x of 13 plants all white. Plant E, crossed with plant D, which 
