5 
of P is .40. The odds are approxi- 
mately 1.5 to 1 against the observed 
deviations being due to chance only. 
Such odds are, however, not considered 
as seriously vitiating the hypothesis of 
independent inheritance of ry and su. 
The preceding facts demonstrate 
that the chlorophyll abnormality of 
albino seedlings is not linked with 
either the sugary character nor the 
aleurone factor ry. Factors w, su and 
r are each on separate chromosomes. 
RELATION BETWEEN DWARFNESS AND 
VIRESCENT-WHITE SEEDLINGS 
Dwarfness in maize is a simple Men- 
delian recessive to the tall normal type. 
The virescent-white character is also 
a simple recessive to normal green. 
Virescent-white seedlings contain very 
little chlorophyll at first, but under fav- 
orable conditions of light and tempera- 
ture, they gradually assume a light 
green color. It has been possible to 
bring some of them to maturity. 
TABLE II: Seedling Progenies from Self- 
pollinated Normal Green Plants Heterozy- 
gous for Tall-dwarf and Green- 
Virescent-white 
Tall Dwarf 
Vires- Vires- 
Pedigree | Tall cent- |Dwarf} cent- 
No. Green| white |Green| white 
2862 63 24 27 11 
2871 52 21 20 6 
2991 57 19 16 5 
2992 52 22 20 7 
3017 178 52 52 11 
Total 402 138 135 40 
Theoretical) 402 134 134 45 
(9:3:3:1) 
Several green plants heterozygous 
for the virescent-white factor (Vv) were 
pollinated by homozygous green, dwarf 
plants. The F, progeny was all tall 
and dark green. When self-pollinated 
the F, plants produced, as was to be 
expected, two sorts of seedling prog- 
enies. One sort consisted entirely of 
green seedlings, the other segregated 
into green and virescent-white. Both 
sorts segregated into tall and dwarf 
seedlings. The segregation into tall 
green, dwarf green, tall virescent-white 
27 The Journal of Heredity 
and dwarf virescent-white which oc- 
curred in five of the progenies was dis- 
tinct, as can readily be seen in Fig. 23. 
Seedling counts were made of the 
five progenies that showed segregation 
into the four classes noted above. They 
are recorded in Table II. 
The data in this table conform 
closely to a 9:3:3:1 ratio and accord- 
ingly indicates that dwarfness and 
virescent-white chlorophyll are inher- 
ited independently of each other. 
Hence, the chlorophyll factor v is not 
in the same chromosome as the dwarf 
factor concerned in this cross. 
RELATION BETWEEN DWARFNESS AND 
XANTHOPHYLL PIGMENT 
In addition to the white and vires- 
cent-white chlorophyll types, there is 
a third type which also is recessive to 
normal green. This recessive char- 
acter is seen in maize seedlings that 
develop a distinct yellow color appar- 
ently due to the pigments xantho- 
phyll and carotin. 
A tall green plant, which produced 
75% green and 25% yellow seedlings 
when self-pollinated, was crossed by a 
dwarf plant. This dwarf was of the 
semi-tall type with anthers in the ear. 
It is also a simple recessive to the tall 
type, but is caused by a different gen- 
etic factor than the dwarf type used in 
the virescent-white cross. 
The F, plants of this cross were all 
tall and normal green. Three of them 
were self-pollinated and their seedling 
progenies tested in the greenhouse. 
All three showed approximately 25% 
dwarf seedlings, which are easily dis- 
tinguished as can be seen from Fig. 24. 
Two of the progenies also segregated 
for the yellow seedling character, pro- 
ducing tall green, dwarf green, tall 
yellow and dwarf yellow in proportions 
indicated in Table III. 
An analysis of this table shows that 
the actual results obtained do not agree 
very closely with the theoretical ex- 
pectancy of a 9:3:3:1 ratio. The ex- 
treme classes (tall green and dwarf 
yellow) taken together are deficient 
while the middle classes (tall yellow 
and dwarf green) are slightly in excess 
