IV PREFACE. 



single germ, or from a few germs It would 

 seem, from the frequency with which this notion 

 is revived, — ever returning upon us with hydra- 

 headed tenacity of life, and presenting itself 

 under a new form as soon as the preceding one 

 lias been exploded and set aside, — that it has a 

 certain fascination for the human mind. This 

 arises, perhaps, from the desire to explain the 

 secret of our own existence ; to have some sim- 

 ple and easy solution of the fact that we live. 



I confess that there seems to me to be a repul- 

 sive poverty in this material explanation, that is 

 contradicted by the intellectual grandeur of the 

 universe ; the resources of the Deity cannot be so 

 meagre, that, in order to create a human being 

 endowed with reason, he must change a monkey 

 into a man. This is, however, merely a personal 

 opinion, and has no weight as an argument ; nor 

 am I so uncandid as to assume that another may 

 not hold an opinion diametrically opposed to mine 

 in a spirit quite as reverential as my own. But I 

 nevertheless insist, that this theory is opposed to 

 the processes of Nature, as far as we have been 

 able to apprehend them ; that it is contradicted 

 by the facts of Embryology and Paleontology, 

 the former showing us norms of development at 



