does not always mean the
same thing. Even the adherents of the general, but in itself quite vague
view that a transformation from lower forms to higher, and from similar to
different forms, has taken place, may present so many points of
disagreement, and may even stand in such antagonism to one another, that
onlookers are apt to receive the impression that they occupy quite
different standpoints, and are no longer at one even in the fundamentals
of their hypotheses.

The most diverse questions and answers crop up; whether evolution has been
brought about "monophyletically" or "polyphyletically," _i.e._, through
one or many genealogical trees; whether it has taken place in a continuous
easy transition from one type to another, or by leaps and bounds; whether
through a gradual transformation of all organs, each varying individually,
or through correlated "kaleidoscopic" variations of many kinds throughout
the whole system; whether it is essentially asymptotic, or whether
organisms pass from "labile" phases of vital equilibrium by various
halting-places to stable states, which are definitive, and are, so to
speak, the blind alleys and terminal points of evolutionary possibilities,
_e.g._, the extinct gigantic saurians, and perhaps also man. And to these
problems must be added the various answers to the question, What precedes,
or may have preceded, the earliest stages of life of which we know? Whence
came the first cell? Whence the first living protoplasm? and How did the
living arise from the inorganic? These deeper questions will occupy us in
our chapter on the theory of life. Some of the former, in certain of their
aspects, will be considered in the sixth chapter, which deals with factors
in evolution.

The Theory of Descent itself and the differences that obtain even among
its adherents can best be studied by considering for a little the works of
Reinke and of Hamann.

Reinke, Professor of Botany in Kiel, has set forth his views in his book,
"Die Welt als Tat,"(25) and more recently in his "Einleitung in die
theoretische Biologie" (1901). Both books are addressed to a wide circle
of readers. Reinke and Hamann both revive some of the arguments and
opinions set forth in the early days of Darwinism by Wigand,(26) an author
whose works are gradually gaining increased appreciation.

It is Reinke's "unalterable conviction" that organisms have evolved, and
that they have done so after the manner of fan-shaped genealogical