the individual in its
efforts to obtain its supplies. On the other hand, development
along lines of small growth, in that reproduction is less costly,
will probably lead to increased rate of reproduction. It is, in
fact, matter of general observation that in the case of larger
animals the rate of reproduction is generally slower than in the
case of smaller animals. But the rate of reproduction might be
expected to have an important influence in determining the
particular periodicity of the organism. Were we to depict in the
last diagram, on the same time-scale as Man, the vibrations of
the smaller and shorter-lived living things, we would see but a
straight line, save for secular variations in activity,
representing the progress of the species in time: the tiny
thrills of its units lost in comparison with the yet brief period
of Man.

The interdependence of the rate of reproduction and

93

the duration of the individual is, indeed, very probably revealed
in the fact that short-lived animals most generally reproduce
themselves rapidly and in great abundance, and vice versa. In
many cases where this appears contradicted, it will be found that
the young are exposed to such dangers that but few survive (_e.g._
many of the reptilia, etc.), and so the rate of reproduction is
actually slow.

Death through the periodic rigour of the inanimate environment
calls forth phenomena very different from death introduced or
favoured by competition. A multiplicity of effects simulative of
death occur. Organisms will, for example, learn to meet very
rigorous conditions if slowly introduced, and not permanent. A
transitory period of want can be tided over by contrivance. The
lily withdrawing its vital forces into the bulb, protected from
the greatest extremity of rigour by seclusion in the Earth; the
trance of the hibernating animal; are instances of such
contrivances.

But there are organisms whose life-wave truly takes up the
periodicity of the Earth in its orbit. Thus the smaller animals
and plants, possessing less resources in themselves, die at the
approach of winter, propagating themselves by units which,
whether egg or seed, undergo a period of quiescence during the
season of want. In these quiescent units the energy of the
organism is potential, and the time-energy function is in
abeyance. This condition is, perhaps, foreshadowed in the
encyst-

94

ment of the amoeba in resistance to drought. In most cases of
hibe