22 
CECIL YAMPOf^SKY 
» ditic flowers) to show a definite influence of that condition upon the sex 
ratios in the offspring. 
Banta (191 6) reports the appearance of intersexes in a phyllopod, 
Limocephalus vetulus. The females reproduce parthenogenetically. "In 
one of the strains there appeared a large percentage of males together with 
normal females and a large number of sex intergrades — males with one or 
more female secondary sex characters, females with one to several male 
characters, and some hermaphrodites with various combinations of male 
and female secondary sex characters." Eight secondary sex characters 
distinguish the male from the female. The highly male-like female inter- 
grades are relatively infertile. The more the female takes on the male 
characters the less likely she is to be fertile. Some individuals with several 
secondary male characters prove to be very fertile. "In general in addi- 
tion to being more prolific one may say that female intergrades with few or 
less distinctly male characters produce a smaller percentage of males and 
sex intergrades than those having a larger number of more definitely male 
characters." Males that show one or more female secondary sex characters 
nearly always have an incompletely developed reproductive system. By 
propagating from female intergrades, Banta was able to secure the produc- 
tion of mixed broods, males, females, and sex intergrades. The stock de- 
rived from these females consists of 40 percent normal males, 8 percent nor- 
mal females, and the rest intergrades with almost any combination of male 
and female secondary and primary sex characters. Some of his sex inter- 
grades (female) may parthenogenetically produce normal females and 
occasionally normal males. 
In a later paper, Banta (19 18) reports on sex intergrades in Daphnia 
longispina. In this form the male differs from the female in eight secondary 
sex characters. In Daphnia there are fewer male than female intergrades. 
The offspring of the more highly male female intergrades tend to be like the 
mother. A female from a sex intergrade will produce offspring very much 
like herself with few male secondary sex characters. The more male the 
female intergrade, the more sterile she is likely to be. 
Banta makes the following suggestive remark: "From such clear cases 
of sex intermediates one wonders if maleness and femaleness are really 
mutually exclusive in those Cladocera individuals which morphologically 
show no unlike sex characters. Even in 'normal' strains one is certainly 
justified in thinking that maleness and femaleness are not complete and 
mutually exclusive states but that in these apparently normal sex forms, 
too, sex is also relative — differing from so-called sex intergrades not in 
kind but merely in degree, not quahtatively but quantitatively." 
Plants show most clearly that maleness and femaleness in the same in- 
dividual do not tend to neutralize each other and to produce sterility. The 
appearance of intersexes or sex intergrades in the plant kingdom, while not 
designated by these terms, has been described for very many forms in the 
