IN BORNEAN FORESTS 



[chap. 



arisen on all sides as to the theory that natural selection is the sole 

 means capable of explaining the raison d'etre of the specific characters 

 of living organisms. 



According to the theory of the plasmation of living beings 

 through the action exerted on them by the environment, every 

 species would be the product of the physical forces and stimuli 

 to which its remote ancestors had been subjected. For this reason 

 every animal and every plant ought to bear in its own structure 

 the traces of its first origin. Even in familiar talk it is generally 



Fig. 41. FOETUS OF ORANG, SIDE VIEW. 



admitted that each climate has left its mark on the organisms 

 living within its influence. 



The varied forms assumed by those groups of individuals called 

 by naturalists species, would be merely the result of a plasmative 

 force exerted by surrounding conditions on primitive beings ; 

 and from a certain point of view it might be said that species 

 represent the impression of which the stimuli, in general, have been 

 the stamp or matrix. 



Thus a careful and minute investigation of the structure of any 

 given species ought to lead to the knowledge of the circumstances 



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