l agree in pointing out the _petitio
principii_ involved in the assumption that the archetype represents the
ancestral form; both reject the simplicist conception of a monophyletic
evolution (which may be likened to the "one animal" idea of the
transcendentalists); both admit the possibility that evolution has taken
place along many separate and parallel lines, and explain the
correspondences shown by these separate lines by the similarity of the
intrinsic laws of evolution; finally, both emphasise the fact that we
know nothing of the actual course of evolution save the few indications
that are furnished by palaeontology, and both insist upon the unique
importance of the palaeontological evidence.[542]

It was a curious but very typical characteristic of evolutionary
morphology that its devotees paid very little attention to the positive
evidence accumulated by the palaeontologists,[543] but shut themselves up
in their tower of ivory and went on with their work of constructing
ideal genealogies. It was perhaps fortunate for their peace of mind that
they knew little of the advances made by palaeontology, for the evidence
acquired through the study of fossil remains was distinctly unfavourable
to the pretty schemes they evolved.

As Neumayr, Zittel, Deperet, Steinmann and others have pointed out, the
palaeontological record gives remarkably little support to the ideal
genealogies worked out by morphologists. There is, for instance, a
striking absence of transition forms between the great classificatory
groups. A few types are known which go a little way towards bridging
over the gaps--the famous _Archaeopteryx_, for example--but these do not
always represent the actual phylogenetic links. There is an almost
complete absence of the archetypal ancestral forms which are postulated
by evolutionary morphology. Amphibia do not demonstrably evolve from an
archetypal Proamphibian, nor do mammals derive from a single generalised
Promammalian type. Few of the hypothetical ancestral types imagined by
Haeckel have ever been found as fossils. The great classificatory groups
are almost as distinct in early fossiliferous strata as they are at the
present day. As Deperet says in his admirable book,[544] in the course of
a presentation of the matured views of the great Karl von Zittel, "We
cannot forget that there exist a vast number of organisms which are not
connected by any intermediate links, and that the relations between the
great