IN MEMORIAM: CHARLES DARWIN 



But just here the facts of geological succes- 

 sion are reinforced, with truly overwhelming 

 conclusiveness, by the great facts of classifica- 

 tion in the animal and vegetable kingdoms. This 

 branching tree-like arrangement, which alone 

 correctly represents the relationships of organ- 

 isms in their geological succession, is at the same 

 time the only possible arrangement by which 

 the likenesses and affinities among existing or- 

 ganisms can be represented with anything like 

 an approach to correctness. The facts of palae- 

 ontology exactly dovetail in with those of tax- 

 onomy, and serve to elucidate and emphasize 

 them. Many eminent naturalists before Cuvier 

 attempted to classify all animals in a linear series, 

 but Cuvier proved once for all that no such 

 arrangement is possible. The only feasible 

 arrangement is that of groups within groups, 

 diverging like the branches and twigs of what we 

 aptly term a " family-tree ; " and this fact not 

 only strongly suggests the theory of " descent 

 with modifications," but is indeed utterly in- 

 compatible with any other theory. 



Further powerful evidence in favour of the 

 same view is furnished by countless familiar facts 

 of morphology and embryology. On the theory 

 of" descent with modifications," it is intelligible 

 that all the classes and orders of the vertebrate 

 sub-kingdom, for example, should be con- 

 structed on exactly the same fundamental plan, 

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