CHAPTER V. 



DARWIN'S great work "On the Origin of Species 

 by means of Natural Selection, or the Preser- 

 vation of Favoured Races in the Struggle for Life," was 

 published in November, 1859. It begins with the 

 simplest narrative of the events leading to its publication, 

 and an apology for the imperfection of "this abstract." 

 The author is well aware, he says, that on most points he 

 deals with, facts can be adduced which often apparently 

 lead to conclusions directly opposite to his own. He 

 states clearly the important truth that a mere belief in 

 the origin of species by descent from other species is 

 unsatisfactory until it can be shown how species can have 

 been modified so as to acquire their present remarkable 

 perfection of structure and coadaptation. Consequently 

 cases of observed modification of species are of the 

 highest value, and precedence is given to the variation of 

 animals and plants in a state of domestication. 



The individuals belonging to the same variety of any 

 of our long-cultivated animals or plants differ much more 

 from each other than the individuals of any one species 

 or variety in a state of nature. Darwin explains this by 



