106 EVOLUTION 



specialized, retains traces of all the func- 

 tions of protoplasm, and that therefore any 

 one of these may be indefinitely increased 

 by favourable conditions, and the specialized 

 function similarly reduced to a trace. Our 

 notion of specialization becomes thus asso- 

 ciated with a corresponding possibility of 

 simplification, and our idea of progress thus 

 becomes complemented and checked by the 

 possibility of degeneration, and this from 

 any stage of the ascent of life. The first 

 of these views is the neo-Darwinian; while 

 the second savours of neo-Lamarckianism; 

 but here, happily, is a case in which the 

 recent admirable eirenicon of Lloyd Morgan, 

 Osborn and Baldwin (discussed in Chapter 

 VI) may be conveniently applied. Accord- 

 ing to this, the modifications of the indi- 

 vidual in response to environment, to use 

 and disuse, in themselves non-heritable 

 though they may be, may yet serve as the 

 nurse and shield and selective vantage- 

 ground for germ-variations in the same 

 direction. With this two-fold process at 

 work, in germs and in developing adults, 

 the frequent development of parasitic shoots 

 upon the tree of life becomes a less per- 

 plexing marvel. 



Another interest of this subject is the way 

 in which it invites that comparison of the 



