seems inevitable effect of process of reproduction. But more
important is that simple <?> generation, especially under new conditions
[when no crossing] <causes> infinite variation and not direct effect of
external conditions, but only in as much as it affects the reproductive
functions{39}. There seems to be no part (_beau ideal_ of liver){40} of
body, internal or external, or mind or habits, or instincts which does
not vary in some small degree and [often] some <?> to a great amount.

{37} The importance of exposure to new conditions for several
generations is insisted on in the _Origin_, Ed. i. p. 7, also p.
131. In the latter passage the author guards himself against the
assumption that variations are "due to chance," and speaks of "our
ignorance of the cause of each particular variation." These
statements are not always remembered by his critics.

{38} Cf. _Origin_, Ed. i. p. 10, vi. p. 9, "Young of the same
litter, sometimes differ considerably from each other, though both
the young and the parents, as Mueller has remarked, have apparently
been exposed to exactly the same conditions of life."

{39} This is paralleled by the conclusion in the _Origin_, Ed. i.
p. 8, that "the most frequent cause of variability may be
attributed to the male and female reproductive elements having been
affected prior to the act of conception."

{40} The meaning seems to be that there must be some variability in
the liver otherwise anatomists would not speak of the 'beau ideal'
of that organ.

[All such] variations [being congenital] or those very slowly acquired
of all kinds [decidedly evince a tendency to become hereditary], when
not so become simple variety, when it does a race. Each{41} parent
transmits its peculiarities, therefore if varieties allowed freely to
cross, except by the _chance_ of two characterized by same peculiarity
happening to marry, such varieties will be constantly demolished{42}.
All bisexual animals must cross, hermaphrodite plants do cross, it seems
very possible that hermaphrodite animals do cross,--conclusion
strengthened: ill effects of breeding in and in, good effects of
crossing possibly analogous to good effects of change in condition <?>{43}.

{41} The position of the following passage is uncertain. "If
individuals of two widely different varieties be allowed to cross,
a third race will be formed--a