I EXPERIMENTAL TEST NECESSARY 45 



of the matter, and do our utmost to bring about the 

 transmutation of any species. We do not specially 

 desire to transform any one species into another 

 known at present ; we wish to transform it into a new 

 species. And this is necessary, if we do not wish to 

 remain open to an objection suggested by the facts of 

 dimorphism. Many species occur in two or more forms, 

 sometimes very different, and if we were merely to 

 transmute one species into another, it might be said 

 that we had mistaken the two forms of a dimorphic 

 species for two different species, and then our attempt 

 would be useless to a large extent. 



Experimental transformism is what we need now, 

 and therein lies the only method we can use. 



But it must be demonstrated that this test is avail- 

 able, and it remains to show what are the facts which 

 lie at its basis, and what are the methods to be used. 



