t was made to construct an indirect proof
by a comparison of bodily-organs. But in so doing the Descent
theorizers had to relinquish scientific analysis altogether.

In conclusion Fleischmann states that he does not mean to discard every
hypothesis of Descent. He simply gives warning against an
over-estimation of the theory. In opposition to those who esteem it as
the highest achievement of science, he looks upon it as a necessary
evil. Its proper sphere is the laboratory of the man of science, and
not the thronging market-place.

"The Descent hypothesis will meet the same fate (be cast aside), since
its incompatibility with facts of ordinary observation is manifesting
itself. At the time of its appearance in a new form, forty years ago,
it exercised a beneficial influence on scientific progress and induced
a great number of capable minds to devote themselves to the study of
anatomical, palaeontological and evolutionary problems. Meanwhile,
however, viewed in the light of a constantly increasing wealth of
actual materials, the hypothesis has become antiquated and the labors
of its industrious advocates makes it obvious to unbiased critics, that
it is time to relegate it ad acta."

* * * * * * *

My own views agree with those of Fleischmann as presented above, except
in regard to his last chapter. I must, of course, admit that his
criticism has discredited the doctrine of Descent as a scientifically
established theory. Hence, as I have always asserted, it must be
excluded from the realm of exact science. No doubt people will come
gradually to see that the theory involves a creed and therefore belongs
to the domain of cosmic philosophy. All this I readily admit.

Not so, however, as regards the concept of "development." It seems to
me to be incorrect to regard this as a logical concept only, even with
reference to organisms. True, the whole zoological system is in reality
nothing more than a logical abstraction. And in view of this fact one
must be on one's guard against confusing a logical transformation of
concepts with a genealogical development.

We must, however, not forget that we possess the wonderful analogy of
ontogeny (individual development) and above all, the fact of mutation
and of metagenesis. And even if we wish to avoid the error of Haeckel
and others who find a necessary connection between ontogeny and
phylogeny, nevertheless the analogy will still entit