tion, its occasional interruption and its temporary cessation
and is likewise the principal cause of the division of the series of
organisms into species."

Lamarck's theory of the use and disuse of organs and Darwin's
hypothesis of natural selection are consequently pushed into the
background. Here also Eimer at once places himself at variance with
Naegeli who had enunciated a similar theory. Naegeli took as a starting
point an inherent tendency in every being to perfect itself, thus
presupposing an "inner principle of development," and making light of
external influences as transforming causes. Eimer flatly contradicts
this view. We shall revert to this point in our criticism of his
theory. In opposition to the theory of selection, Eimer lays special
stress on the fact that its underlying assumption, viz., fortuitous,
indefinite variation in many different directions, is entirely devoid
of foundation in fact, and that selection, in order to be effective,
postulates the previous existence of the required useful characters,
whereas the very point at issue is to explain how these characters have
originated. Since, therefore, according to Eimer's investigations,
there are everywhere to be found only a few, definitely determined
lines of variation, selection is incapable of exercising any choice.
The development, furthermore, proceeds without regard for utility,
since, for instance, the features that characterize a species of plants
are out of all reference to utility. "Even if nothing exists that is
essentially detrimental, nevertheless very much does exist that bears
no reference whatever to immediate good, and was therefore never
affected by selection."

Further on, Eimer expresses still more clearly the opposition of his
theory to that of Darwin, and in so doing he attacks vigorously the
omnipotence of selection, so unreasonably proclaimed by the followers
of Darwin. Eimer's theory, consequently, asserts that: "The essential
cause of transmutation is organic growth, a definite variation, which,
during long periods of time proceeds unswervingly and without reference
to utility, in but few directions and is conditioned by the action of
external influences, of climate and nourishment." In consequence of an
interruption of orthogenesis a stoppage ensues in certain stages of the
development, and this stoppage is the great cause of the arrangement of
forms in different species. Of vital importance also "is development
thro