h in a Creator and Master
of the world, called wide-spread attention to it; and the theory opened to
natural science itself entirely new impulses and paths, and promised the
solution of many problems before which it had hitherto been compelled to
stand in silence. To be sure, it threatened likewise to allure the mind
from the slow but sure ways of solid study to the entertaining but insecure
and aimless paths of imagination and hypothesis.

Among all the German followers of Darwin who adopted not only the idea of
an origin of species through descent and evolution, but also the
explanation of evolution by natural selection, and extended it so as to
make the principle of selection of exclusive value, Ernst Haeckel occupies
the most prominent rank.

In his "General Morphology," published in 1866, and in his "Natural History
of the Creation," the first edition of which appeared in 1868, and finally
in his "Anthropogeny"[2] (why he does not say Anthropogony, we are nowhere
informed), 1874, this scientist brought the new theory, which had been
presented by Darwin in an almost bewildering flood of details, into
connection and order, and, analyzing the powers active in natural
selection, combined them into an entire system of laws. He {46} at once
drew the origin of man also into the course of reasoning on the new theory,
and sustained the theory by the discovery of the _monera_ and other low
organisms of one cell, as well as by special investigations of the
calcareous sponges. For these labors, he was rewarded by the warm and
unreserved acknowledgment which Darwin made to him in his work upon the
origin of man, which was published subsequently to the "Natural History of
the Creation." There Darwin says: "If this work had appeared before my
essay had been written, I should probably never have completed it. Almost
all the conclusions at which I have arrived, I find confirmed by this
naturalist, whose knowledge on many points is much fuller than mine."
Haeckel's labors rendered still greater service to the Darwinian theory by
dividing the organic world into three kingdoms: the protista kingdom, the
vegetable kingdom, and the animal kingdom,--a division which solves in a
most simple way the difficulty that was felt more and more of securing for
the lowest organisms a place among the animals or plants. He further aided
the theory by leaving the choice open to adopt either a uniform or
multiform pedigree of the organisms and their k