Chap. IV. DIVERGENCE OF CHARACTER. Ill 



instances could be given showing how quickly new breeds 

 of cattle, sheep, and other animals, and varieties of 

 flowers, take the place of older and inferior kinds. In 

 Yorkshire, it is historically known that the ancient black 

 cattle were displaced by the long-horns, and that these 

 " were swept away by the short-horns " (I quote the 

 words of an agricultural writer) " as if by some mur- 

 derous pestilence." 



Divergence of Character. — The principle, which I have 

 designated by this term, is of high importance on my 

 theory, and explains, as I believe, several important 

 facts. In the first place, varieties, even strongly- 

 marked ones, though having somewhat of the character 

 of species — as is shown by the hopeless doubts in many 

 cases how to rank them — yet certainly differ from each 

 other far less than do good and distinct species. Never- 

 theless, according to my view, varieties are species in 

 the process of formation, or are, as I have called them, 

 incipient species. How, then, does the lesser difference 

 between varieties become augmented into the greater 

 difference between species ? That this does habitually 

 happen, we must infer from most of the innumerable 

 species throughout nature presenting well-marked dif- 

 ferences ; whereas varieties, the supposed prototypes 

 and parents of future well-marked species, present slight 

 and ill-defined differences. Mere chance, as we may 

 call it, might cause one variety to differ in some cha- 

 racter from its parents, and the offspring of this variety 

 again to differ from its parent in the very same cha- 

 racter and in a greater degree ; but this alone would 

 never account for so habitual and large an amount of 

 difference as that between varieties of the same species 

 and species of the same genus. 



As has always been my practice, let us seek light on 



