| 1 résultat  | books.google.fr While he was engaged in substantially classifying and describing not merely the
forus already in existence, but also their extinct ancestors which he incorporated
into his system, there was disclosed to him the inner morphologic connection
between the former and the latter, and from this disclosure he inferred their
common descent. All animal and vegetable forms which we distinguish as
species, possess, accordingly, but a relative temporary persistence, and the
varieties are the ... |
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