to more or less complex arrangements, so that the cross
section of the strand represents the configuration of the idioplasm.[B]

[B] Naegeli makes his idioplasm ramify throughout the organism in
unbroken continuity, much like a system of nerves in the higher
animals. This idea with Naegeli was purely speculative. It was
known that the protoplasm is in connection throughout the
organism, but it has been proved more recently that only the
somatic protoplasm is thus connected. The part in which the
essential nature of the organism is contained is localized
in the nucleus and hence might properly be designated as
nucleoplasm, as Weismann suggests. If the idioplasm is
localized in the nucleus, it cannot be continuous throughout
the system, as Naegeli assumes. But this objection applies only
to a detail of the theory and does not affect the fundamental
conception,--that of a portion of the protoplasm which is
differentiated from the rest and represents a definite molecular
structure which determines the specific nature of the
organism.--_Trans._

Each ontogeny (individual) begins in a minute germ cell, in which a
small quantity of idioplasm is contained. In the cell divisions, by
which the organism grows, the idioplasm divides into as many parts as
there are single cells, while it continually increases in quantity in a
corresponding degree. The ontogenetic increase of the idioplasm takes
place by length growth of the strands--that is, by intercalation of
micellae in each row of cells of the strands, which thereby grow in
length without changing the configuration of the cross section.[C]
Accordingly, each strand of idioplasm contains all the determinants that
the particular individual has inherited in the germ cell, and each cell
of the organism is idioplasmatically qualified to become the germ cell
of a new individual. Whether this qualification may be realized depends
upon the nature of the soma-plasm. In the lower plants this power
belongs to each individual cell; in the higher plants many cells have
lost it; in the animal kingdom it is possessed in general only by cells
normally set apart as asexual or sexual reproductive cells.

[C] Hence, according to Naegeli, every cell of the organism has
idioplasm of identical structure. This at once suggests the
objection, how can the idioplasm, for instance, of a pollen
grain be the same as that of a