ANATOMICAL SYSTEMS.

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liarities. The most striking of its features is the prin-ciple laid down that the type of development of animalsis one and the same from Man to the Monad, implying acomplete negation of the principle advocated by Cuvier ,that the four primary divisions of the animal kingdomare characterized by different plans of structure. It isvery natural that Ehrenberg, after having illustrated sofully and so beautifully as he did the natural history ofmany organized beings, which, up to the publication ofhis investigations, were generally considered as entirelyhomogeneous ; after having shown how highly organizedand complicated the internal structure of many of themis ; after having proved the fallacy of the prevailingopinions respecting their origin,—should have been led tothe conviction that there is, after all, no essential differ-ence between these animals, which were then regarded asthe lowest, and those which were, placed at the head ofthe animal creation. The investigator who had justrevealed to the astonished scientific world the compli-cated systems of organs which can be traced in the bodyof microscopically small Eotifera must have been ledirresistibly to the conclusion that all animals are equallyperfect, and have assumed, as a natural consequence ofthe evidence he had obtained, that they stand on thesame level with one another, as far as the complicationof their structure is concerned. Yet the diagram of hisown system shows that he himself could not resist theinternal evidence of their unequal structural endowment.Like all other naturalists, he places Mankind at one endof the animal kingdom, and such types as have alwaysbeen considered as low at the other end.

Man constitutes, in his opinion, an independent cycle,that of nations, in contra-distinction to the cycle of

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