say that pure morphology in
the Geoffroyan or Okenian sense was becoming gradually discredited. A
curious indication of this is seen in the fact that not only the idea
but the very word "Archetype" came to be regarded with suspicion. Thus
even J. V. Carus, who had much affinity with the transcendentalists,
wrote of the vertebrate archetype (which he took over almost bodily from
Owen)--"It may here be observed that this schema may be used as a
methodological help, but it is not to be placed in the foreground"
(_loc. cit._, p. 395). Huxley, who was definitely a follower of von
Baer, was much more outspoken with regard to ideal types. In an
important memoir on the general anatomy of the Gastropoda and
Cephalopoda,[318] he set himself the task of reducing all their complex
forms to one type. In summing up, he writes:--"From all that has been
stated, I think that it is now possible to form a notion of the
archetype of the Cephalous Mollusca, and I beg it to be understood that
in using this term, I make no reference to any real or imaginary 'ideas'
upon which animal forms are modelled. All that I mean is the conception
of a form embodying the most general propositions that can be affirmed
respecting the Cephalous Mollusca, standing in the same relation to them
as the diagram to a geometrical theorem, and like it, at once imaginary
and true" (i., p. 176). Again, in his Croonian lecture on the theory of
the vertebrate skull, he remarks that a general diagram of the skull
could easily be given. "There is no harm," he continues, "in calling
such a convenient diagram the 'Archetype' of the skull, but I prefer to
avoid a word whose connotation is so fundamentally opposed to the spirit
of modern science" (_Sci. Memoirs_, vol. i., p. 571).

It is instructive to find that between Serres and Milne-Edwards there
existed the same antagonism as between von Baer and the German
transcendentalists. Milne-Edwards was a constant critic of the law of
parallelism which Serres continued to uphold with little modification
for over thirty years, just as von Baer was a critic of that form of the
doctrine which was current in the early part of the century. As early as
1833, Milne-Edwards, through his studies of crustacean development,[319]
had come to the conclusion, independently of von Baer, that development
always proceeded from the general to the special; that class characters
appeared before family characters, generic characters before specific.