1 8 THE EVOLUTION OF MAN. 



cell of all other animals. When in my "History of Creation" 

 I had discussed this fundamental fact, and had directed 

 attention to its immense significance, several theological 

 periodicals pronounced it a malicious invention of my own. 

 The evident fact that at a certain stajje of their evolution 

 the embryos of Man and of the Dog are entirely in- 

 distinguishable from one another was also denied. 



The fact is that an examination of the human embryo in 

 the third or fourth week of its evolution shows it to be 

 altogether different from the fully develoj^ed Man, and that 

 it exactly corresponds to the undeveloped embryo-form 

 presented by the Ape, the Dog, the Rabbit, and other 

 Mammals, at the same stage of their Ontogen}^ At this 

 stage it is a bean-shaped body of very simple structure, 

 with a tail behind, and two pairs of paddles, resembling the 

 fins of a fish, and totally dissimilar to the limbs of man and 

 other mammals, at the sides. Nearly the whole of the front 

 half of the body consists of a shapeless head without a face, 

 on the sides of which are seen gill-fissures and gill-arches 

 as in Fishes. (C£ Plate VII. at the end of Chapter XI.) 

 In this stage of evolution the human embryo differs in no 

 essential way from the embryo of an Ape, Dog, Horse, Ox, 

 etc., at a corresponding age. Even such facts as these, 

 which can be easily and promptly demonstrated at any time 

 by placing side by side the corresponding embryos of Man, 

 a Dog, a Horse, etc., have been spoken of by theologians 

 and teleological philosophers as inventions of materialism ; 

 and even naturalists, who were presumably acquainted with 

 them, have tried to deny them. No stronger proof, surely, 

 of the immense radical importance of these embryological 

 facts in favour of the monistic philosophy can be given than 



