330 EVOLUTION, OLD AND NEW. 



to refer modification to the direct action of a changed 

 environment. 



Mr. Herbert Spencer. 



" Those who cavalierly reject the theory of Lamarck 

 and his followers as not adequately supported by facts," 

 wrote Mr. Herbert Spencer,* "seem quite to forget that 

 their own theory is supported by no facts at all " in- 

 asmuch as no one pretends to have seen an act of direct 

 creation. Mr. Spencer points out that, according to the 

 best authorities, there are some 320,000 species of plants 

 now existing, and about 2,000,000 species of animals, 

 including insects, and that if the extinct forms which 

 have successively appeared and disappeared be added 

 to these, there cannot have existed in all less than some 

 ten million species. " Which," asks Mr. Spencer, " is the 

 most rational theory about these ten millions of species ? 

 Is it most likely that there have been ten millions of 

 special creations ? or, is it most likely that by continual 

 modification due to cliange of circumstances, ten millions 

 of varieties may have been produced as varieties are 

 being produced still ? " 



****** 



" Even could the supporters of the ^development 

 hypothesis merely show that the production of species 

 by the process of modification is conceivable, they 

 would be in a better position than their opponents. 

 But they can do much more than this ; they can show 

 that the process of modification has effected and is 

 effecting great changes in all organisms, subject to 

 * See ' The Leader,' March 20, 1852, " The Haythorae Papers." 



