duction, on the part of the organism, is
represented by a line which repeats the curvature of the parent
organism originating at such a point as P in the path of the
latter, when the rate of consumption of energy has become
constant. The organism A has now ceased to act as a unit. The
products of fission each carry on the vital development of

{Fig. 2}

the species along the curve B, which may be numbered (2), to
signify that it represents the activity of two individuals, and
so on, the numbering advancing in geometrical progression. The
particular curvature adopted in the diagram is, of course,
imaginary; but it is not of an indeterminate nature. Its course
for any species is a characteristic of fundamental physical
importance, regarding the part played in nature by the particular
organism.

88

In Fig. 2 is represented the path of a primitive multicellular
organism before the effects of competition produced or fostered
its mortality. The lettering of Fig. 1 applies; the successive
reproductive acts are marked P1, P2; Q1, Q2, etc., in the paths
of the successive individuals.

{Fig. 3}

The next figure (Fig. 3) diagrammatically illustrates death in
organic history. The path ever turns more and more from the axis
of energy, till at length the point is reached when no more
energy is available; a tangent to the curve at this point is at
right angles to the axis of energy and parallel to the time axis.
The death point is reached, and however great a length we measure
along the axis of time, no further consumption of energy is

89

indicated by the path of the organism. Drawing the line beyond
the death point is meaningless for our present purpose.

It is observable that while the progress of animate nature finds
its representation on this diagram by lines sloping _upwards_ from
left to right, the course of events in inanimate nature--for
example, the history of the organic configuration after death, or

{Fig. 4}

the changes progressing--let us say, in the solar system, or in
the process of a crystallisation, would appear as lines sloping
downwards from left to right.

Whatever our views on the origin of death may be, we have to
recognise a periodicity of functions in the life-history of the
successive individuals of the present day; and whether or not we
trace this directly or indirectly to

90

a sort of interference with the rising wave of life, imposed by
the activity of a series of derived units,