I digress here in order to give an account of the intimate processes,
which, according to my view, take place within the germ-plasm, and which I
have called "GERMINAL SELECTION." These processes are of importance since
they form the roots of variation, which in its turn is the root of natural
selection. I cannot here do more than give a brief outline of the theory
in order to show how the Darwin-Wallace theory of selection has gained
support from it.

With others, I regard the minimal amount of substance which is contained
within the nucleus of the germ-cells, in the form of rods, bands, or
granules, as the GERM-SUBSTANCE or GERM-PLASM, and I call the individual
granules IDS. There is always a multiplicity of such ids present in the
nucleus, either occurring individually, or united in the form of rods or
bands (chromosomes). Each id contains the primary constituents of a WHOLE
individual, so that several ids are concerned in the development of a new
individual.

In every being of complex structure thousands of primary constituents must
go to make up a single id; these I call DETERMINANTS, and I mean by this
name very small individual particles, far below the limits of microscopic
visibility, vital units which feed, grow, and multiply by division. These
determinants control the parts of the developing embryo,--in what manner
need not here concern us. The determinants differ among themselves, those
of a muscle are differently constituted from those of a nerve-cell or a
glandular cell, etc., and every determinant is in its turn made up of
minute vital units, which I call BIOPHORS, or the bearers of life.
According to my view, these determinants not only assimilate, like every
other living unit, but they VARY in the course of their growth, as every
living unit does; they may vary qualitatively if the elements of which they
are composed vary, they may grow and divide more or less rapidly, and their