THE HUMAN FORM 323 



mutations of other organic types, the structural mutations 

 that led from Invertebrates up to Vertebrates were due to 

 the volume acquired by the nervous system, whose centres, 

 especially the brain, thereupon gradually perfected themselves. 

 It is, above all, in the size and the special arrangement of his 

 brain that Man differs from the other Vertebrates. 



That which has raised man above the animals whose structure 

 he retains, and which inspires the horror he feels at the idea of 

 kinship with them, is his consciousness of exceptional 

 mentality. Nevertheless, we must acquiesce in the knowledge 

 that we are made, like the lowliest of living creatures, from a 

 few common substances. The white corpuscles of oar blood 

 have retained the structure and amoeboid movements of the 

 lowest of the rhizopod Protozoa ; the olfactory membrane 

 of our nose, our trachea, and various other of our body cavities 

 are lined with cells provided with vibratile cilia like those of 

 the Infusoria ; our nerve-cells have a common external 

 character with those of all other animals ; our muscular fibres 

 do not differ essentially from those of other Vertebrates, and 

 even had their counterparts in certain Invertebrata ; our body 

 is divided into segments like the segments of the Worm ; our 

 teeth do not differ from the resistant plates which form the 

 dermal skeleton of the Sharks, and of which the teeth of these 

 Fishes are but a modification ; the scales of Fish have formed 

 the bones of the vault of their skull — and of our own, as 

 Geoffroy Saint-Hilaire discovered ; our sternum and clavicles 

 are allied with the external bony plates of Batrachians. As 

 in them, so in the human embryo are there rudimentary 

 branchial arches, and the Batrachians inherited theirs from the 

 Ctenobranch Fishes. We reproduce our kind by means of cells 

 similar to the reproductive cells of all other living creatures, 

 and the development of our body is modelled on that of 

 the Reptiles, the Birds, and the humblest Mammals. 



We must resign ourselves to these affinities. Whatever we 

 may think, we shall never have bodies made of moonbeams 

 like Victor Hugo's sylphs, nor shimmering wings like those 

 outspread by Wells' angel in the course of the "Wonderful 

 Visit " he imprudently paid to our earth. On the other hand, 

 we may take the greater pride in our intelligence since our 

 body has been its work, and because in our evolution — 

 paradoxical as it may appear — mind has ever dominated 



