Aug. i8, 19*3 
Inheritance of Dwarfing in Maize 
3“ 
with factors for broad leaves. This would be brought about if dwarf 
plants were included among the brachytic plants in the classification 
into groups. The frequency polygon for stature in the brachytic group 
shows clearly that there is no bimodality, and an examination of the 
short, broad-leaved plants in this group fails to show any of the other 
dwarf characters, such as few tassel branches or perfect flowered ears, 
eliminating the possibility that the plants were classified improperly. 
A further substantiation of the dwarflike characteristics of certain 
brachytic plants is found in the negative correlation between length and 
width of leaf, a correlation which is positive in both the normal and 
dwarf groups. Almost as unexpected is the rather high positive corre¬ 
lation of length with width of leaf in the dwarf group, the group which 
as a whole has short wide leaves. The restoration of the normal physio¬ 
logical correlation indicates that there is no segregation of varying 
degrees of dwarf ness as such in this group, but rather that such variation 
as exists is due to the effects of environment or possibly to unrelated 
modifying factors. 
The correlation of width of leaf with number of tassel branches in both 
the dwarf and brachytic groups are much smaller than the correlation 
in the normal group, though all three are positive. The coefficients in 
the brachytic and dwarf groups do not depart significantly from zero, 
while the coefficient in the normal group clearly is significant. The fact 
that the normal physiological relationship of wide leaves and many 
tassel branches has been largely reduced in the brachytic and dwarf 
groups indicates that a genetic cause is involved, an indication which 
derives support, of course, from the fact that the dwarf parent represents 
a condition where not only relatively wide but actually wide leaves are 
associated with few tassel branches. 
The number of tassel branches shows no other unusual relationhips. 
The correlations with total number of leaves were not calculated for 
other than the normal group, since on both brachytic and dwarf plants a 
large number of leaf tags were lost. 
Thus the population of these groups was reduced, and since the loss of 
tags was in inverse proportion to the height of the plants a selective 
action was involved which might result in spurious relationships so that 
correlation coefficients would be of little value if calculated. 
INHERITANCE OF TERATOLOGICAL VARIATIONS 
STAMINATE EAR SPIKES 
The percentage of plants with staminate ear spikes in the whole F, 
population, including normal, brachytic, and dwarf plants, is 40.9± 1.14. 
The three groups of stature—normal, brachytic, and dwarf, had, respec¬ 
tively, 26.2±1.28, 18.2 ±2.27, and 99.4±o.4 per cent of the plants with 
staminate spikes. 
The difference in percentage of this character between the normal and 
brachytic groups is 8. o ±2.6 i , or 3.06 times the error. Yule’s coefficient 
of association between normal stature and the development of staminate 
spikes in the normal-brachytic population is only 0.229 ±0.074, while 
the departure from a 50 per cent crossover ratio as measured by x 2 is 
3.71. It may be concluded, therefore, that the brachytic and normal 
groups are alike with respect to the development of staminate ear spikes, 
both approximating 25 per cent. The hypothesis has been advanced 
