116 PROF. ERNEST W. MACBRIDE, M.A., F.R.S., ON 



uncertain. His conclusion was that upon the application of those 

 methods many supposedly valid biological theories have shrunk to 

 nothing, and he says : " Possibly this may be the fate of the 

 natural-selection theory." I do not know what later evidence there 

 may be. 



The last paragraph of the paper refers to the Amoeba. May I 

 inquire whether any recent researches have shown that the Amoeba, 

 which is to be found in all parts of the world, ever evolves into an 

 organism of a higher character 1 



The article " Protozoa," in the Encyclopcedia Britannica, concludes 

 by saying that the origin of life is veiled in a mist which biological 

 knowledge in its present state is unable to dispel. But if the Amoeba 

 in past ages evolved into higher organisms, what reason can be given 

 why it should not be doing so now 1 



On p. 102 mention is made of natural species and elementary 

 species, and I gather that by elementary species is intended what 

 by some authors are called sub-species, or even varieties. But 

 Mr. Erich Wasmann, in his book, Modern Biology and the Theory of 

 Evolution, propounds the theory of a distinction between what he 

 calls " systematic species " and " natural species," and he looks upon 

 the natural species as having been originally created, and the 

 systematic species as having, often in many thousands, sprung from 

 them ; and in this way he thinks that the theories of creation and 

 descent can easily be reconciled with one another. 



In connection with this idea I may call attention to a passage in 

 Professor Bateson's address at Melbourne, in which he said : — 



" We should be greatly helped by some indication whether the 

 origin of life has been single or multiple. Modern opinion 

 is perhaps inclining to the multiple theory, but we have no 

 real evidence." 



Oskar Hertwig expressed a similar opinion in an address in 1900 

 on " Biology in the Nineteenth Century " (p. 44) : — 



"If we would form an hypothesis as to the descent of the 

 present world of living organisms from simple original 

 cells in the earliest times, the polyphyletic hypothesis has 

 certainly much more probability than the monophyletic." 

 Dr. J. Reinke, of the University of Kiel, says {Principles of Biology, 

 1909, p. 170 (Heilbronn) ) :— 



