202 THE INHERITANCE OF CHARACTERS IN RICE, I 
Red rice, grey-brown rice and anthocyan pigmentation. 
The relation between red and grey-brown rice was considered in Part I, 
p. 101, and later results, with their probable explanation, were given in a 
postscript. It was shown that, in the families there concerned, the red rice. 
colour only developed in plants with purple pigmentation, its place being taken 
by grey-brown in unpigmented plants. It was suggested that the pigmentation 
factor concerned was necessary, in addition to a red rice factor, for the 
production of red rice, and that in its absence the red rice factor produced 
only grey-brown. The existence of unpigmented varieties with red rice was 
explained on the assumption that the pigmentation factor lacking in such 
varieties was different from that lacking in the families under consideration. 
This theory has now been confirmed by the results of certain crosses. 
It has already been shown, Part I, p. 88, that the presence of two factors 
is necessary for the production of purple (anthocyan) pigmentation. These 
factors are denoted by 4d and NV, the red rice factor by R, in the description 
that follows. 
Taking A as the pigmentation factor connected with rice colour, d R 
will be red, a R will be grey-brown. Thus the 9: 3:5: TJ ratio, made up of 
3:1, red: white, inthe pigmented group and 3: J, grey-brown : white, in the 
unpigmented group, as shown by Table XXI in the posteript of Part I, is the 
expected result from a parent of the constitution da NN Rr. The simple 
3:1 ratio of pigmented, red: unpiqmented, grey-brown is the result from 
AaNNER. 
An unpigmented, grey-brown, aa N N RR, from the latter type of segre- 
gation, was crossed with a pigmented, white variety, A A N Nr, and gave a 
pigmented, red F,, da N N Rr. In F, the expected 9: 3: 3:1 ratio 
resulted, four families giving the following figures :— 
| PIGMENTED | UNPIGMENTED 
| | 
| Red White | Grey-brown White 
| ANR ANr | a NR aNr 
Nos. 1512-1515 ee 1,785 602 | 587 184 
Juices: aoe 8 7 1,776 592 592 197 
A more interesting cross was between the same wunpigmented, grey- 
brown aaN N RR, and an unpigmented, white of the constitution 
