> 
‘ 
34 BULLETIN 54, U. S. DEPARTMENT OF AGRICULTURE. 
that the Chinese plant was producing gametes cR cR. The cross is 
shown by the following diagram: 
all white waxy (observed). 
Self 
Chinese cR : 
\-8 ~ all colored (observed). 
Hybrid Dh 234 CR, Cr? ~~ 
Self. 25 per cent white (observed 26 per cent). 
An F, plant of the hybrid Dh 237 was pollinated with Chinese, 
and the resulting ear had 54.1 per cent white, while a second ear of 
the Dh 287 plant, when self-pollinated, had 25.2 per cent white. As : 
Dh 237 segregating 3 colored seeds to 1 white, when self-pollinated, 
has been assumed to have the composition CH cP, a Chinese plant 
producing only c# gametes would be expected to give 50 per cent 
“white when crossed with Dh 287 segregating 3 colored to 1 white, 
_as In the following diagram: 
Chinese cR 
NE 
Hybrid Dh 237 CR, cR <Q : 
50 per cent white (observed 54.17 per cent). 
Self. 25 per cent white (observed 25.2 per cent). 
COMPOSITION IN THE SECOND GENERATION OF THE HYBRID 
DH 234. 
The hybrid Dh 234 had 46 ears, which were obtained from 31 
plants, many plants having two ears. Of these 46 ears, 25 were the 
result of self-pollination, 12 were the result of fertilization by sister 
plants of the same hybrid, and 9 were the result of pollinating the 
hybrid Dh 234 with pollen from the hybrid Dh 237. There ap- 
peared to be no difference among these three groups as to the per- 
centage of seeds with colored aleurone, so that they were all tabulated 
together and arranged numerically by pedigree numbers. Two ears 
from a single plant are indicated by a bracket inclosing the pedigree 
numbers of the ears. 
The 46 ears are shown in Table XV. The total number of seeds 
for these ears is 26,383, with 25.8 per cent white, the expected being 
25 per cent, a deviation of 0.8 per cent, which is 4.45 times the prob- 
able error. The individual ears ranged from 21.4 per cent white to 
30.9 per cent white, making a continuous series. Five of the ears 
deviated above the expected in percentage by an excess of three times 
the probable error, two of these deviating by four times the probable 
error. Of the 46 ears, 830 had white seeds in excess of the expected 
number, 13 below the expected percentage, and 3 were exactly 25 
per cent white. 
