Evolution of Evolution-Theory. 237 



Thus, what is the relative frequency of continuous 

 and discontinuous variations? In what proportion are 

 observed variations merely individual or possibly racial ? 

 What are the causes of germinal variations? Are so- 

 matogenic modifications in any degree transmissible? 

 What is and has been the scope and rigour of natural 

 elimination? To what extent is isolation demonstrable? 

 These and a score of similar questions are at present 

 unanswerable. 



It is not that we are where we were forty years ago. 

 It is rather that we have become more aware of our 

 ignorance and of the complexity of the problem. 



Easy enough it is to express opinion, e.g. that there 

 must be something after all in the Lamarckian and 

 Buffonian position, though one is at a loss to explain 

 the mechanism of heredity whereby modifications of the 

 body could be transmitted; that many, from Geoffrey 

 St. Hilaire to Bateson, have shown evidence for leaps 

 and bounds in evolution; that Nageli, Eimer, and a 

 dozen others have been on the track of undiscovered 

 laws of progressive growth ; that Darwin and Wallace 

 were right in insisting on the importance of natural 

 elimination, though it may not be so all-sufficient as is 

 often supposed; that Romanes and Gulick disclosed a 

 new factor in expounding the various forms of " isola- 

 tion"; that Weismann has done well to expose the 

 credulity of belief in the inheritance of acquired charac- 

 ters, though he may have exaggerated the negative 

 position; and that the same naturalist's hypotheses as 

 to the origin of variations are at present most welcome 

 stop-gaps in our aetiology. But opinion has no place 

 in science. 



It is then a thiitige Skepsis which appears the healthi- 

 est mood at present. Not of course that this is any- 

 thing new; it is a constantly recurrent phase, alike in 

 the individual and in the race. Indeed, the rate of 

 intellectual progress in either may perhaps be measured 

 by the more or less rapid recurrence of the sceptical phase. 



Lamarckianism was in its way a very satisfactory 

 theory until its weak points were discovered; Darwin 

 went, though in another direction, one better; Weis- 



