364 THE EVOLUTION OF MAN. 



development are undoubtedly identical with those of the animals standing 

 directly below him in the scale ; without the slightest doubt, he stands in 

 this respect nearer the ape tban the ape does to the dog." THOMAS HUXLEY 

 (1863). 



THE most important phenomenon, having a general bearing, 

 that we have so far met with in the process of human germ- 

 history, is surely the fact that the development of the 

 human body proceeds from the beginning in exactly the 

 same way as that of other Mammals. All the special 

 peculiarities of individual development which distinguish 

 Mammals from all other animals are found also in Man. 

 Long ago, from the physical structure of the perfect Man 

 the conclusion was drawn that his natural position in the 

 system of the animal world can only be in the mammalian 

 class. In 1735 Linmeus, in his Systema Naturcc, placed 

 Man in one and the same class with the Apes. This position 

 is fully corroborated by comparative germ-history. We 

 have evidence that, no less in embryonic development than 

 in anatomical structure, Man closely resembles the higher 

 Mammals, and especially the Apes. If we now seek, by 

 applying the fundamental biogenetic law, to understand this 

 ontogenetic agreement, the perfectly simple and necessary 

 conclusion is that Man is descended from other mammalian 

 forms. Hence we can no longer doubt the common descent 

 of Man and the other Mammals from a single primaeval 

 parent-form, or hesitate to believe that the blood-relation- 

 ship is closest between Men and Apes. 



This essential harmony between the embryo of Man 

 and of the other Mammals, in their whole bodily form and 

 internal structure, exists even in that latest age of develop- 

 ment, in which the mammalian body, as such, is already 



