An individual could never inherit character from its paternal grandmother.
This, of course, is contrary to the results of ordinary Mendelian
experiments, for characters are inherited equally from individuals of
either sex, except secondary sexual characters and sex-linked characters
which we shall consider later.

Similarly, if we suppose that segregation of ovum and sperm occurs in the
female, the sperms must disappear and the ovum would contain no factors
derived from the male parent. But the theory supposes that the segregation
of male and female does occur in the female, that half the ova are female
and half are male. What meaning are we to attach to the words 'male ovum'
or even 'male producing ovum'? It is a fundamental principle of Mendelism
that the soma does not influence the gametocytes or gametes; we have
therefore only to consider the sex of the gametes themselves, derived from
a zygote which is formed by the union of two sexes. The quality of
maleness consists only in the size, form, and mobility of the sperm in the
higher animals and of the microgamete in other cases. In what sense then,
can an ovum be male? It may perhaps be said that though it is itself
female, it has some property or factor which when united with a sperm
causes the zygote to be capable of producing only sperms, and conversely
the female ovum has a quality which causes the zygote to produce only ova.
But since these qualities segregate in the reduction divisions, how is it
that the male quality in the _f_ ovum does not make it a sperm? We are
asked to conceive a quality, or the absence of a factor, in an ovum which
is incapable of causing that ovum to be a sperm, but which, when
segregated in the gametes descended from that ovum, causes them all to be
sperms. It is impossible to conceive a single quality or factor which at
different times produces directly opposite effects. The Mendelian theory
is merely a theory in words, which have an apparent relation to the facts,
but which when examined do not correspond to any real conceptions.