STUDIES ON THE GENETICS OF FLOWER-COLOURS, ETC. 
131 
on account of the small number of the cases which I have encountered 
till now. 
1. One white plant derived ex orange X white-I (Table I, p. 98) has 
produced besides white flowers some orange-coloured ones. Two of the latter 
were selfed, and seeds thus obtained have given rise in the next year to 14 
plants which have borne, not orange flowers as was expected, but white ones 
simply. Some white flowers on the original plant were selfed, but seeds got 
from them did not germinate. As the second generation did not bear orange 
flowers, the phenomenon will not belong properly to bud-mutation. 
2. One white i^-plant derived ex white-I X orange has produced one 
branchlet bearing orange flowers. These as well as one white flower were 
selfed. Only two seeds from the former came to germination, and one of the 
plants thus produced has so far developed as to bear one flower which was 
magenta ; three seeds taken on the white flower had germinated and developed 
to 2 magentas and 1 wange. 
3. One white plant among the A’-offspring ex red x white-I has borne 2 
white flowers and 1 magenta one. No seeds could be obtained from the 
former, but those got on the latter has produced in the next year 3 plants, 
viz. 2 magentas and 1 white, thus the magenta flower was proven to have 
been heterozygous in its genotypic constitution. 
4. One white plant among the A'-progeny ex white-II x magenta has 
borne besides white flowers one magenta one in 1920. Whether the latter 
is homo- or heterozygous will be examined in this year, because I have got 
seeds on this flower. 
Summary. 
1. All coloured varieties of PoHulaca grandiflora are characterised by 
possessing the factor C. 
2. C alone gives rise to orange flower-colour. C and 6r produce 
together yelloio flower-colour, C and It together red ; whilst the magenta 
colour is due to the co-operation of the three factors, C, It and 74 
3. As to the genetics of flesh-coloured and “pseudo-white ” races my 
experiments are not so far advanced as to be able to fully establish their 
respective genotypic constitution. 
