286 Xou-Isolable Races 
marckiana. In the normal families of my cultures some 
specimens that happened to be variegated had, after arti- 
ficial self-fertilization, given rise to no more than two 
per cent of variegated offspring and in the next genera- 
tion the same proportion was repeated, the conditions be- 
ing the same. From these I selected in 1898 the four 
finest young plants, planted them out a meter apart, and 
thereby obtained strong, richly-branched individuals, of 
which some were slightly, and others strongly, variegated. 
On all of them the flowers from which I intended to save 
seed were artificially and purely fertilized with their own 
pollen. On each of the four plants I first fertilized 
flowers on the pure green and afterwards some on the 
variegated lateral branches. Amongst 675 seedlings of 
the former and 1300 of the latter group the seeds pro- 
duced the following percentages of yellow and variegated 
seedlings : 
PL\NTS PERCENTAGE IN VARIEGATED SEEDLINGS 
GREEN BRANCHES VARIEGATED BRANCHES 
No. 1 0-0 % 1 % 
No. 2 3 
No. 3 0-0 4-12-18 
No. 4 0-0 6-9-45-100 
Each number refers to a separate branch The six 
greens gave rise, as we see, to green seedlings only, but 
the variegated ones to a larger or smaller number of 
seedlings with this character. The figures 1, 3, 4, and 
45 in the last column relate to the slightly variegated 
branches ; the rest to those with this character more 
strongly developed. The latter therefore gave a higher 
percentage of variegated offspring. The variegated seed- 
lings had either vellow or flecked cotvledous, or o-reen 
f C5 
cotyledons and flecked leaves, and of these three groups 
there were 68% of the first, 12% of the second and 20% 
