The Making of Species 



The former are the larger body, and pin their 

 faith absolutely to natural selection. They deny 

 the inheritance of acquired characters, and preach 

 the all-sufficiency of natural selection to explain 

 the varied phenomena of nature. The Neo- 

 Lamarckians do not admit the omnipotency of 

 natural selection. Some of them allow it no 

 virtue. Others regard it as a force which keeps 

 variation within fixed limits, which says to each 

 organism, " thus far shalt thou vary and no 

 farther." This school lays great stress on the 

 inheritance of acquired characters, especially 

 on the inheritance of the effects of use and 

 disuse. 



The above statement of the recent develop- 

 ments of Darwinism is incomplete, for it fails to 

 include those who occupy a middle position. If 

 it be possible to classify a large number of men 

 of which scarcely any two hold identical views, 

 it is into three, rather than two, classes that they 

 must be divided. 



Speaking broadly, evolutionists of to-day may 

 be said to represent three distinct lines of thought. 

 For the sake of classification we may speak of 

 them as falling into three schools, which we may 

 term the Neo-Lamarckian, the Wallaceian, and 

 the Neo- Darwinian, according as their views in- 

 cline towards those held by Lamarck, Wallace, 

 or Darwin. 



As adherents of the Neo-Lamarckian school, 



