Studies on the Variability and Heritability of Pigmentation in Oenothera. 345 
Table 3. 
O. rubrinervis, 1.35. September 28, 1907. 35 buds. 
o eae ae ee ee te eee 
x.(4—5).g | x | x 
x | ZH 8: | x 
x. 4 ME: x 
(4—5) x.p x 
(4—5) | 
4-5) x | x(4—7) 
| x | x 
| (4-5) x x(4—7) 
| (4-5) 
| xD x 
| (4-5) | 
| (45) 
(45) x 
(45) 
x x 
x x | 
Sum of classes with regard | | | 
only to extent of red. . . | 3 | | I 7 
Adding 50% of the interme- | | | 
diates to each adjacent. . 3 825 [es I 7 
Adding together classes 4, 5 | | | 
and 6, in which the extent | | 
of red. is the same. ... 3 25 | 7 
p= paler red than type. 
g= more green than type. 
the presence of a bud in any class, and the class O is added for the 
occasional buds which show no red at all. The various combinations 
employed are also easily understood. The first part of the formula 
represents the extent of the color pattern and the second part the 
depth of shade. Thus 2.(4—5) indicates that the extent of the color 
pattern is as in fig. 2, while the depth of color is between figs. 4 and 
5 (plate VI). 
In collecting material for this study, all the buds of an individual 
were collected which would open on that day or, in some cases, on 
the next. The color pattern reaches its full development before this 
time, though growth continues. The buds were examined and recorded 
immediately after collecting. When one side of a bud has its color 
pattern more fully developed than another, the former side is chosen 
