2O THE EVOLUTION OF MAN. 



But I must here add at once, that our knowledge of the 

 evolution of functions is as yet far from being so advanced 

 as our knowledge of the evolution of forms. Indeed, properly 

 speaking, the entire history of evolution, or Biogeny, includ- 

 ing both Ontogeny and Phylogeny, has as yet been almost 

 exclusively a history of the evolution of forms, while the 

 Biogeny of functions hardly exists even in name. The fault 

 lies solely with Physiology, which has as yet scarcely given 

 a thought to the history of evolution, which it has left 

 entirely to the care of Morphology. 



The two chief divisions of biological research Mor- 

 phology and Physiology have long travelled apart, taking 

 different paths. This is perfectly natural, for the aims, as 

 well as the methods, of the two divisions are different. 

 Morphology, the science of forms, aims at a scientific under- 

 standing of organic structures, of their internal and external 

 proportions of form. Physiology, the science of functions, 

 on the other hand, aims at a knowledge of the functions 

 of organs, or, in other words, of the manifestations of life. 13 

 Physiology, however, has, especially during the last twenty 

 years, been far more one-sided in its progress than Mor- 

 phology. Not only has it entirely neglected to apply the 

 comparative method, by which Morphology has gained its 

 greatest results, but it has altogether disregarded the History 

 of Evolution. Hence it has come to pass that, within the 

 past few decades, Morphology has advanced far beyond 

 Physiology, although the latter is pleased to look haughtily 

 down upon the former. It is Morphology which has gained 

 the greatest results in the fields of Comparative Anatomy 

 and Biogeny, and almost everything stated in these pages- 

 as to the History of the Evolution of Man, is due to the 



