kel's great work on morphology,
and it has ever since been a guiding principle in his important
philosophical studies.

It was through this same work on morphology that Haeckel first came
to be universally recognized as the great continental champion of
Darwinism--the Huxley of Germany. Like Huxley, Haeckel had at once made
the logical application of the Darwinian theory to man himself, and he
sought now to trace the exact lineage of the human family as no one had
hitherto attempted to fathom it. Utilizing his wide range of zoological
and anatomical knowledge, he constructed a hypothetical tree of
descent--or, if you prefer, ascent--from the root in a protozoon to
the topmost twig or most recent offshoot, man. From that day till this
Haeckel's persistent labors have been directed towards the perfection of
that genealogical tree.

This work on morphology was much too technical to reach the general
public, but in 1868 Haeckel prepared, at the instigation of his friend
and confrere Gagenbaur, what was practically a popular abridgment of
the technical work, which was published under the title of _The Natural
History of Creation_. This work created a furor at once. It has been
translated into a dozen languages, and has passed through nine editions
in the original German. Through it the name of Haeckel became almost
a household word the world over, and subject for mingled applause
and opprobrium--applause from the unprejudiced for its great merit;
opprobrium from the bigoted because of the unprecedented candor with
which it followed the Darwinian hypothesis to its logical goal.

The same complete candor of expression has marked every stage of the
unfolding of Professor Haeckel's philosophical pronouncements. This
fact is the more remarkable because Professor Haeckel is, so far as I am
aware, the only scientist of our generation who has felt at liberty to
announce, absolutely without reserve, the full conclusions to which his
philosophy has carried him, when these conclusions ran counter to the
prevalent prejudices of his time. Some one has said that the German
universities are oases of freedom. The remark is absolutely true of
Jena. It is not true, I believe, in anything like the same degree of any
other German university, or of any other university in the world. One
thing before others that has endeared Jena to Haeckel, and kept him
there in the face of repeated flattering calls to other universities, is
that full liberty