May, 1923] VALLEAU — INHERITANCE IN THE STRAWBERRY 
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sufficient to produce fertile pistils (wild female) while one dose of maleness 
is not sufficient to produce functional stamens. This plant would then be 
a female. The only records on this individual, which was grown in the 
greenhouse, stated that it was female and had berries strikingly like the 
berries borne on the original wild female. The berries borne on its sibs 
were all much of a type and more intermediate between its parents, although 
most Fi plants of F. virginiana, when a pistillate is used as a female parent, 
resemble the wild to quite a degree. If we are correct in the assumed 
constitution of this female, and if it is crossed with Glenville, the expected 
combinations would be as follows: hH (female) X HH 1 (Glenville in which 
H is a normal hermaphrodite and H is a weak hermaphrodite or male) 
= 1 hH (a fertile female) : 1 hH 1 (a female sterile or producing only nubbins): 
1 HH (a fertile hermaphrodite) : 1 HH 1 (a partially fertile or sterile her¬ 
maphrodite of the Glenville type). These are in fact the types which were 
produced. A similar explanation might be given for the origin of the 
completely sterile wild clones of F. virginiana which are occasionally found 
in which neither the stamens nor the pistils are functional. It is not 
maintained that this is the correct explanation of the results obtained. It is 
based on the assumption that the male and female determiners in an her¬ 
maphroditic chromosome are separate and distinct, and that, as a conse¬ 
quence, crossovers might occur between them. The four types of plants 
were very distinct, and the numbers were so large as to indicate a genetic 
condition different from any previously studied. 2 
Although the results thus far given all point to the hermaphrodites 
being homozygous for sex determiners, and the pistillates heterozygous, 
they are not absolutely conclusive, since the progeny of selfed females have 
not yet been studied. This I believe will be impossible in the strawberry, 
as I have never found a stamen on any of the cultivated pistillate varieties 
or on wild pistillate clones which showed any signs of producing pollen. 
If, however, we can transfer the sterile male condition of the wild F. virgin¬ 
iana to progeny through the use of a wild F. virginiana female with fertile 
hermaphrodites, it would seem that we have proved its heterozygous 
condition for F and M. This seems to have been done in the cross 5/15 
(table 3) in which a wild F. virginiana $ was the pistillate parent and the 
very fertile hermaphrodite 778 was the male parent. This cross produced 
18 pistillates, all fertile to a high degree, and 18 hermaphrodites. Nine of 
the hermaphrodites were completely fertile, 4 were fertile except for an 
occasional tertiary or quaternary flower, while 5 set only an occasional fruit. 
On the theory that pistillates are heterozygous, the genetic constitution of 
the wild female would be FM and that of the hermaphrodite HH. The 
female progeny of this cross would then all be FH or FH 1 and would be 
completely fertile. The constitution of the hermaphroditic progeny would 
2 The other case in which a female was nearly sterile resulted from the cross 65/16, 
Columbus X Glenville, which produced 9 hermaphrodites and 11 females, 10 of which 
were completely fertile while one produced only nubbins. 
