t of the biological sciences--the founding of comparative
embryology by Baer (1828) and of the cell-theory by Schleiden and
Schwann (1838), the advance of physiology under Johannes Muller (1833),
and the enormous progress of palaeontology and comparative anatomy
between 1820 and 1860--provided this necessary foundation. Darwin was
the first to coordinate the ample results of these lines of research.
With no less comprehensiveness than discrimination he consolidated them
as a basis of a modified theory of descent, and associated with them
his own theory of natural selection, which we take to be distinctive
of "Darwinism" in the stricter sense. The illuminating truth of these
cumulative arguments was so great in every branch of biology that,
in spite of the most vehement opposition, the battle was won within a
single decade, and Darwin secured the general admiration and recognition
that had been denied to his forerunner, Lamarck, up to the hour of his
death (1829).

Before, however, we consider the momentous influence that Darwinism has
had in anthropology, we shall find it useful to glance at its history
in the course of the last half century, and notice the various theories
that have contributed to its advance. The first attempt to give
extensive expression to the reform of biology by Darwin's work will be
found in my "Generelle Morphologie" (1866) ("Generelle Morphologie
der Organismen", 2 vols., Berlin, 1866.) which was followed by a more
popular treatment of the subject in my "Naturliche Schopfungsgeschichte"
(1868) (English translation; "The History of Creation", London,
1876.), a compilation from the earlier work. In the first volume of the
"Generelle Morphologie" I endeavoured to show the great importance
of evolution in settling the fundamental questions of biological
philosophy, especially in regard to comparative anatomy. In the second
volume I dealt broadly with the principle of evolution, distinguishing
ontogeny and phylogeny as its two coordinate main branches, and
associating the two in the Biogenetic Law. The Law may be formulated
thus: "Ontogeny (embryology or the development of the individual) is a
concise and compressed recapitulation of phylogeny (the palaeontological
or genealogical series) conditioned by laws of heredity and adaptation."
The "Systematic introduction to general evolution," with which the
second volume of the "Generelle Morphologie" opens, was the first
attempt to draw up a natural sys