Feb. 23,1924 
Teosinte Maize Hybrids 
593 
Number of rows of aeicoees on best spike. —With the number of 
rows of alicoles on the best spike, which is one of the outstanding differ¬ 
ences between maize and Euchlaena, there are no significant disherent 
correlations. It is interesting to observe that this character is negatively 
correlated with the measures of height as well as with season. 
Number of doubee femaee aeicoees on best spike. —The number 
of double female alicoles and the number of single female alicoles, which 
in a certain sense are two complementary characters, both show signifi¬ 
cant genetic correlations, and no clear disherences. It seems noteworthy 
that where the number of double female alicoles is negatively correlated 
with the measures of height and season, the number of single female 
alicoles is positively correlated with these characters. 
Number of spikes in prophyeeary. —The number of spikes in the 
prophyllary inflorescence has four significant correlations which represent 
disherences, but these all may be due to the interaction of physiological 
factors. On the other hand, there are several coefficients which can best 
be attributed to genetic causes. 
AeicoeE index. —This index measures the proportion of single female 
alicoles, which is one of the outstanding differences between maize and 
teosinte. It is of interest to observe that in this character there is but 
one significant disherence, and many clear genetic correlations. 
Days to poeeen and days to seek. —With length of season as meas¬ 
ured by the number of days from planting to anthesis and silking there 
are several significant disherences, the most outstanding being those with 
the number of spikes in the prophyllary inflorescence and the number of 
days between anthesis and the appearance of the first silk. The negative 
correlations with the number of spikes in the prophyllary inflorescence 
are contrary to expectation on both physiological and genetic grounds, 
while the positive correlations with days from pollen to silk might be 
attributed to the advancing season, with cool weather retarding the 
appearance of silking. 
Days poeeen to seek. —Of the 29 correlations with days from pollen 
to silk, there are only five in excess of three times the error; of these, 
two are disherences. The character as a whole does not seem to be a 
stable one, or one in which much confidence can be placed, though the 
teosinte parent always is proterogynous and the maize parent pro- 
terandrous. 
Average EENGTH of internode. —There is one significant disherence 
with the average length of the internode on the best branch, namely, 
that with diameter of culm; but since it has been apparent throughout 
that physiological factors have affected the diameter of the culm to the 
almost complete exclusion of genetic factors, no importance need be 
attached to this single disherence. 
Rank of The pistieeate infeorescence. —The rank of the pistillate 
inflorescence, where the best spike of each plant was arranged in an 
ascending series from teosinte to maize, and this series was distributed 
among eight fairly definite groups, furnishes a composite measure evalua¬ 
ting all the characters of the spike. A fairly normal frequency distribu¬ 
tion resulted from the grouping of these spikes, and the rank, therefore, 
may be taken as. a fair estimate of the degree of resemblance of the spike 
to maize or teosinte. The correlations with rank should indicate to what 
extent the maizelike form of inflorescence is associated with the other 
characteristics of maize. 
