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AMERICAN JOURNAL OF BOTANY 
[Vol. io, 
be HM and H^M, depending on which of the H chromosomes of 778 com¬ 
bined with the M. What should be the sex of these new genotypes? They 
should be hermaphrodites as far as somatic condition is concerned and 
should be completely fertile, partially sterile, or sterile, depending on the 
extent to which their sex is determined by the hermaphrodite or male 
determiners and on whether the two hermaphrodite determiners have an 
equal or an unequal potential fertility. The hermaphroditic progeny were 
of two classes consisting of 9 completely fertile clones and 9 partially sterile, 
as was previously mentioned. These results would seem to indicate that 
the two H factors of 778 differed slightly in potential fertility and, when in 
combination with the same male factor, resulted in different degrees of 
fertility. This does not necessarily follow, however, as it will be shown 
later that a single H factor of a female plant, when united with the two 
male factors of a wild male, produced progeny showing the same variations 
in fertility. The result, when one of the 5/15 (F. virginiana $ X 778) 
hermaphrodites was selfed, was reported in table 1, 57/16, and was analyzed 
in the following discussion. It was there shown that pure males, completely 
fertile hermaphrodites, and intermediates could be produced from one of 
these HM hermaphrodites. These results prove that the wild females 
carry the factor for maleness, femaleness being completely dominant over 
it, and that the factor for maleness can be transferred through the wild 
female to hermaphroditic progeny, and that, when in combination with an 
hermaphrodite factor, either one may act as a dominant, producing complete 
fertility or sterility, or both may show partial dominance resulting in 
partial fertility. 3 
The question as to whether one hermaphrodite of the constitution HM 
may be fertile and another partially sterile, or whether one H factor may 
be potentially more dominant than another, is extremely important from 
an economic as well as from a scientific standpoint. The case of Glenville, 
previously mentioned, in which the sex varied from male to hermaphrodite 
under different cultural conditions, and which produced, when selfed, both 
fertile and sterile seedlings, is evidence that one of the sex factors may be 
dominant at one time and the other dominant under other conditions. 
Further studies on the relative dominance and potential fertility of the 
H factors in the cultivated strawberry may throw considerable light on the 
reasons why certain varieties fruit heavily under some conditions and pro¬ 
duce an inferior grade of irregularly shaped fruit under other conditions. 
Pistillate X Staminate 
The cross pistillate X staminate should give the same results as pistillate 
X hermaphrodite as far as somatic appearances are concerned. The 
3 Both the H and the M factors must be considered to be recessives, as both are reces¬ 
sive to the F factor. This seems to be true in spite of the fact that the H factor appears 
to carry functional F and M factors linked. 
