Introduction. 15 



of his school an extravagant estimate of the impor- 

 tance of Lamarckian principles. 



But the most novel, and in many respects the 

 most remarkable school of what may be termed 

 Anti-selectionists is one which is now (1894) rapidly 

 increasing both in numbers and in weight, not only 

 in the New World, but also in Germany, and to a 

 lesser extent, in Great Britain. 



This school, without being either Lamarckian or 

 Darwinian (for its individual members differ widely 

 from one another in these respects) maintains a 

 principle which it deems of more importance than 

 either use-inheritance or natural selection. This prin- 

 ciple it calls Self-adaptation. It is chiefly botanists 

 who constitute this school, and its principal representa- 

 tives, in regard to authority, are Sachs, Pfeffer and 

 Henslow. 



Apart from topics which are to be dealt with in 

 subsequent chapters, the only matters of much impor- 

 tance which have been raised in the Post- Darwinian 

 period are those presented by the theories of Geddes, 

 Cope, Hyatt, and others, and certain more or less 

 novel ideas set forth in Wallace's Darwinism. 



Mr. Geddes has propounded a new theory of the 

 origin of species, which in his judgement supersedes to 

 a large extent the theory of natural selection. He has 

 also, in conjunction with Mr. Thomson, propounded 

 a theory of the origin of sex. For my own part, I 

 cannot see that these views embody any principles 

 or suggestions of a sufficiently definite kind to 

 constitute them theories at all. In this respect the 

 views of Mr. Geddes resemble those of Professors 

 Cope, Hyatt, and others, on what they term "the 



