358 PROCEEDINGS OF THE OHIO ACADEMY OF SCIENCE. 



school. Says Conklin : — "When one recalls the storm of oppo- 

 sition which was called forth by his book on the 'Germ-Plasm' 

 the present acceptance, at least in principle, of his major pro- 

 positions can not be viewed in any other light than as a triumph 

 for his theory and a tribute to the insight, foresight and con- 

 structive ability of Weismann." And again, while admitting that 

 "it is probable that Weismann underestimated the possible in- 

 fluence of environment in producing changes in the germ-plasm 

 and hence its influence on evolution," Conklin adds : — "Weis- 

 mann admitted in his later years that the germ-plasm might be 

 inodified to a limited extent by certain environmental conditions, 

 but he held that such changes of the germ-plasm led to general 

 and unpredictable changes in future generations which might 

 be wholly different from these somatic changes in the parents 

 which were directly produced by such environment. This view 

 is now widely accepted. Thus while Weismann's views on this 

 subject underwent certain changes in the course of his long life, 

 the opinions of his opponents have undergone so much greater 

 and more important changes that it may be truly said that in 

 the matter of the inheritance or non-inheritance of acquired 

 characters the greater portion of the scientific world has come 

 to Weismann's position". 



This is a conservative and rational statement ; others are far 

 more radical, and there has been much rash talk about the "omnip- 

 otence of selection" (Weismann's own expression). From the 

 other camp has come equally rash talk of the "deathbed of Dar- 

 winism". The results of evolution are of tremendous extent and 

 almost infinite in their variety ; universal laws in nature are com- 

 paratively rare. Scientific opinion, as well as popular opinion, 

 is like a pendulum, swinging first to one extreme and then to 

 the other ; but it is likely to come to rest in a middle position. 

 And our final theory of evolution is likely to be neither the 

 extreme of Neo-Lamarckism nor the extreme of Neo-Darwinism, 

 but a golden mean, perhaps not so far removed from the original 

 Darwinism of Darwin. 



