The Inheritance of Quantitative Characters in Maize 103 
no genetic correlation between time of maturity of the two sorts 
of flowers, crossing any very early with any very late variety of 
corn, both of which are protandrous, must result always in F 2 
plants more strongly protogynous than any now known and also 
some plants more decidedly protandrous than any known. 
SUMMARY AND GENERAL CONCLUSIONS. 
The object of this paper, as stated in the introduction, is to 
discuss somewhat fully the inheritance of quantitative characters 
and to present data bearing upon this subject secured from ex- 
periments with maize. The results of these experiments, given in 
detail earlier in this paper, are here summarized. 
The inheritance of number of rows per ear has been studied 
in eight different crosses. The parent varieties were of 8-rowed. 
12-rowed, 16-rowed, and 20-rowed types. In nearly every case F x 
was intermediate between the parents, tho in case of one cross of 
an 8-rowed variety with an apparently 12-rowed variety, the latter 
condition seemed to be dominant. In most cases the F 2 genera- 
tions had a wider range of variation than F x , a range that 
included both parent types. Differences between the F 2 families 
of a single cross are believed to have been due to heterozygosis of 
one or other of the parent varieties. Where F 3 families were 
grown, the parent types were recovered in every case and inter 
mediate types were also seen. In one case a series of F 3 lots, 
from a single cross, showed modal conditions of 12, 14, 16, 18, 
and 20 rows. 
Inheritance of length of ears was studied in three crosses of 
distinct varieties. In each case the ear length of one parent was 
approximately two and one-half times that of the other parent. 
In the cross of Tom Thumb with Black Mexican, the F x ear length 
was distinctly intermediate between the parental ear lengths. In 
the cross of Missouri dent with California pop, on the other hand, 
the F x generation had ears practically as long as those of the 
long-eared parent, but here the extreme length of the F x ears was 
doubtless in part due to heterozygosis, for the means of the F 2 
families were distinctly intermediate between the parental means. 
In every case the F 2 fraternities were more variable than the F x 
lots. In most cases the F 2 's completely bridged the gap between 
the parents and in one case the F 2 range of variation was from 
practically the shortest ears of the short-eared parent to beyond 
the longest ears of the long-eared parent. The short-eared parent 
type has not as yet been recovered in any F 3 lot and in only a few 
F 3 families has the ear length been equal to that of the long 
eared parent. In case of each cross, however, the ears of some 
F 3 families averaged nearly twice as long as the ears of other F a 
