364 BOTANICAL GAZETTE [NOVEMBER 
is conceivable that the alternative sexual types may be determined 
in different cases by very different methods, some qualitative, 
some quantitative, and others both qualitative and quantitative. 
In some species the sexes appear to represent a much more strongly 
polarized (?) condition than in other species, and a transition from 
the characters of the one sex to those of the other is attained 
only with the greatest rarity, if at all; while in other species the 
sex conditions may be so nearly balanced or neutral that individuals 
are not so absolutely determined in their sex relations by their 
genotypic nature, thus resulting in ever-sporting varieties in 
respect to sex, such as CorrENS (7) has found in Plantago lanceo- 
ata 
With such a conception of sex, it also appears probable that 
sex may be influenced sometimes by external factors as well as : 
by internal ones, and in this case the preponderance of one sex 
over the other, which has been observed in many animals and 
plants, need not be attributed alone to a selective disorganization 
of germ cells, a selective fertilization, or a selective death rate, 
but might conceivably be controlled to a certain extent by environ- 
mental conditions acting at some particular “sensitive period” 
in the ontogeny of the organism in question. However this may 
be, there is little or no evidence at present that such environmental 
influences on sex can be more than relatively slight in the case of 
dioecious plants and animals. In such organisms recent genetic 
and cytological studies prove conclusively that sex is generally 
determined by the genotypic nature of the individual. 
Summary 
The hermaphrodites of Lychnis dioica are modified males. 
They are of two kinds, which are here distinguished as “genetic” 
and “somatic” hermaphrodites. 
When the genetic hermaphrodites are used as pollen parents, 
either when self-fertilized or in crosses with females, their pros" 
enies consist of females and hermaphrodites. When they are use 
as pistil parents, and fertilized by normal males, they produce 
females and normal males. 
Somatic hermaphrodites may be externally indistinguishable 
