ntermediate between male and female; (6) Like males, but with
rudimentary ovaries and show female traits in some other organs;
(7) Males with a few traces of female origin, notably wing-shape.

The males showed the same graded approach to the female type. Their
instincts likewise became more and more female as the type was modified
in that direction. That is, a moth would be 12% or 35% female, and so
on.

Goldschmidt watched the crosses which produced seven different grades of
maleness in his females. The moth material, like the birds and mammals,
suggested a dual basis for sex in each individual. The grades of
maleness and femaleness made it seem probable that the factor which
determines sex must be stronger in some instances than in others, i.e.,
that the difference between two of these grades of female is originally
quantitative, not qualitative--in amount rather than in kind.

Mating European moths with European, or Japanese with Japanese, produced
pure, uniform sex-types, male and female. But a cross of European with
Japanese strains resulted in intersexes. Goldschmidt concluded that
(1) all individuals carried the genetic basis for both sexes; and
(2) that these basic factors were two chemicals of enzyme nature. One
of these he called Andrase, enzyme producing maleness, the other Gynase,
enzyme producing femaleness. Further, (3) since each chemical sex
determiner is present in both individuals in every cross, there must be
two chemical "doses" of maleness and two of femaleness struggling for
mastery in each fertilized egg. (4) If the total dose of maleness
exceeds the total dose of femaleness, the sex will be male, and
_vice versa_. (5) These quantities get fixed by natural selection
in a single race which always lives in the same environment, i.e., the
doses of maleness and femaleness in a given sex always bear practically
the same relation to each other. Hence the types are fixed and uniform.
(6) But different races are likely to have a different strength of
chemical sex-doses, so that when they are crossed, the ratios of
maleness to femaleness are upset. Often they are almost exactly equal,
which produces a type half male and half female--or 2/3, or 1/3, etc.
The proof of this theory is that it solved the problems. Goldschmidt
was able to work out the strengths of the doses of each sex in his
various individuals, and thereby to predict the exact grade of
intersexuality which would result from a given cross.