Havelock Ellis[18] and G. Stanley Hall[19] have applied the idea of a
"race-type" female with peculiar insistence to the human race. Goodale
has finally killed the bird evidence upon which earlier workers so
largely founded this doctrine, by showing that the "race type" toward
which birds tend unless inhibited by the female ovarian secretion is the
male type, not the female. There is a great difference in the way the
internal secretions act in birds and in man, as will be pointed out
later. It is so important that such a major point as general variability
must be supported and corroborated by mammalian evidence to prove
anything positively for man. As already noted, the statistical studies
of Pearson and Mrs. Hollingworth _et al._ have yielded uniformly
negative results.

In the utilization of data gathered from non-human species, certain
differences in the systems of internal secretion must be taken into
account. Birds differ from the human species as to internal secretory
action in two vital particulars: (a) In the higher mammals, sex depends
upon a "complex" of all the glands interacting, instead of upon the sex
glands alone as in birds; (b) The male bird instead of the female is
homogametic for sex--i.e., the sperm instead of the eggs is uniform as
to the sex chromosome.

Insects are (in some cases at least) like birds as to the odd
chromosome--the opposite of man. But as to secondary sex-characters they
differ from both. These characters do not depend upon any condition of
the sex organs, but are determined directly by the chemical factors
which determine sex itself.[20]

In crustacea, the male is an inhibited female (the exact opposite of