riod than others. Finally, on the views here
given, we certainly gain some clear insight into the wonderful fact that
the child may depart from the type of both its parents, and resemble its
grandparents, or ancestors removed by many generations.

_Conclusion._

The hypothesis of Pangenesis, as applied to the several great classes of
facts just discussed, no doubt is extremely complex; but so assuredly are
the facts. The assumptions, however, on which the hypothesis rests cannot
be considered as complex in any extreme degree--namely, that all organic
units, besides having the power, as is generally admitted, of growing by
self-division, throw off free and minute atoms of their contents, that is
gemmules. These multiply and aggregate themselves into buds and the sexual
elements; their development depends on their union with other nascent cells
or units; and they are capable of transmission in a dormant state to
successive generations.

In a highly organised and complex animal, the gemmules thrown off from each
different cell or unit throughout the body must be inconceivably numerous
and minute. Each unit of each part, as it changes during development, and
we know that some insects undergo at least twenty metamorphoses, must throw
off its gemmules. All organic beings, moreover, include many dormant
gemmules derived from their grandparents and more remote progenitors, but
not from all their progenitors. These almost infinitely numerous and minute
gemmules must be included in each bud, ovule, spermatozoon, and
pollen-grain. Such an admission will be declared impossible; but, as
previously {403} remarked, number and size are only relative difficulties,
and the eggs or seeds produced by certain animals or plants are so numerous
that they cannot be grasped by the intellect.

The organic particles with which the wind is tainted over miles of space by
certain offensive animals must be infinitely minute and numerous; yet they
strongly affect the olfactory nerves. An analogy more appropriate is
afforded by the contagious particles of certain diseases, which are so
minute that they float in the atmosphere and adhere to smooth paper; yet we
know how largely they increase within the human body, and how powerfully
they act. Independent organisms exist which are barely visible under the
highest powers of our recently-improved microscopes, and which probably are
fully as large as the cells or units in one of the higher animals; yet
t