362 BOTANICAL GAZETTE [NOVEMBER 



and carry only the female tendency, while its sperm cells are of two 

 types, one of which has the same sex character as the egg cells, 

 the other bearing the hermaphrodite condition. In my preliminary 

 paper, it was suggested that those eggs may fail to develop which 

 lack the female gene F, or which possess the male gene M; or that 

 in case the female is a negative homozygote, there might be an 

 extrusion of the male gene during oogenesis. As there are no 

 visible cytological differences between the females and the hermaph- 

 rodites, it may not be possible to decide these questions. The 

 relatively small number of seeds in the hermaphrodites, as com- 

 pared with the females, appears to be favorable to a selective elim- 

 ination of male-bearing eggs. Another explanation seems possible. 

 A segregation of the female and male genes may conceivably take 

 place earlier than the time at which the germ cells are formed, 

 though it must be admitted that there is little evidence at present 

 that such early segregations regularly 8 take place in -any plant or 

 animal. Such a suggestion has been made by BATESON (2, p. 159), 

 however, in the effort to account for certain interesting instances 

 of coupling. If a segregation of female and hermaphrodite genes 

 could be assumed to take place as early as the formation of a certain 

 primordial cell from which the entire reproductive tissue of the 

 ovary develops, so that the ovules are supplied only with the female 

 genes, the observed uniformity of the egg cells would result. If 

 segregation may take place thus before the spermacytes are devel- 

 oped, this might also offer an explanation of the exceedingly variable 

 sex ratios which occur in Lychnis, for an unequally rapid develop- 

 ment of tissues derived from female-bearing cells and male-bearing 

 cells, from the moment of segregation until the spermacytes are 

 produced, would give an unequal number of female-bearing and 

 male-bearing sperms, and variability in this process would produce 

 irregular ratios. I place no stress upon this hypothesis, however, 

 and am inclined to look for an explanation of the observed phenom- 

 ena in some sort of selective elimination. 



There remains to be considered the relation of the somatic 

 hermaphrodites to the problems of sex determination. The 

 results under cases XIII and XIV show that the hermaphrodite 



8 They are known to take place occasionally in the production of bud sports. 



