INHERITANCE OF SEX IN MERCURIALIS ANNUA 
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2. Plants with normal hermaphroditic flowers, and hermaphroditic 
flowers with shriveled anthers. 
3. Plants with hermaphroditic flowers with shriveled anthers. 
4. Plants with normal hermaphroditic flowers, hermaphroditic flowers 
with shriveled anthers, and female flowers. 
5. Plants with hermaphroditic flowers with shriveled anthers, and fe- 
male flowers. 
6. Plants with female flowers. 
Some plants which he studied throughout their growth, in the beginning 
showed only hermaphroditic flowers, then passed through the stages noted 
in the classes above, and finally became female plants. These apparent 
females explain, as he thinks, why he secured females in selfed hermaphro- 
ditic cultures in 1903. Correns (1905) explains that in his first cultures he 
had examined the offspring at the end of the season and had not taken into 
account the changes which had taken place during the growing season. 
The 134 females of his hermaphroditic culture were probably hermaphro- 
dites. They produced 252 hermaphrodites and 24 females. Correns 
(1906) finds essentially the same results for Satureja, Silene inflata, and 
S. dichotoma. In Plantago lanceolafa the different forms reproduce their 
like quite well. The author here reiterates the two aws that he had 
formulated as a result of his experiments, namely; (i) Each sex form pro- 
duces germ cells which have the tendency to produce the same form, and 
(2) The tendency of the phylogenetically younger, i.e., those forms which 
have become unisexual, dominates over the hermaphroditic tendency. 
Raunkiaer (1906), a little earlier in the same year, reported on the inheri- 
tance of forms in two gynodioecious species, Knautia arvensis and Thymus 
vulgaris. In Knautia four hermaphrodites produced 80 offspring, 73 
hermaphrodites and 7 females. Six females produced 272 offspring, of 
which 44 were hermaphrodites, 197 females, and 31 gynomonoecious forms. 
Correns (1906) calls attention to the fact that two of Raunkiaer's females 
were really gynomonoecious forms and became female at the time of the 
experiment. In Thymus, female plants produced 44 offspring, 42 of which 
were females and 2 hermaphrodites. 60 offspring of hermaphrodites in- 
cluded 21 hermaphrodites and 39 females. Correns explains this result 
by claiming that those plants which Raunkiaer considered females in his 
offspring were probably gynomonoecious individuals. 
Correns (1908) reports further on the influence of the male germ cells 
on the sex of the individual. Plantago shows many intermediate forms 
between the female and the hermaphrodite. Plants whose sex had been 
determined the previous year were crossed. Thus plant no. 122, female 
with small anther rudiments (sex constant for 3 years), was crossed with the 
hermaphrodite no. 149 and gave 89.9 percent female offspring, the rest 
showing various gradations between hermaphroditic and female. Plant 
no. 122, female, crossed with plant no. 118, hermaphrodite, gave 97 percent 
