JULIUS SACHS. 171 



at a time when the cautious De Bary (in his criticisms of 

 the second edition of the Text-book) looked askance at it. 

 The Archegoniates are treated in the Text-book with special 

 interest, forming part, as they had done, of his own re- 

 searches. His grouping of thallophytes (in the fourth 

 edition of the Text-book), which met with such adverse 

 criticism, has at any rate attained the satisfactory position 

 of being approached again in our own days by many 

 writers. 



Throughout his life he cared little for those details that 

 often fill men's lives, and preferred to view matters from a 

 wide and general standpoint. In the first edition of his 

 Text-book he had set his face against " idealistic morpho- 

 logy " at a time when it was dominant, and in a paragraph 

 of his History that promises to become classical he laid 

 bare the foundations upon which this tendency rested. 



Darwinism was another bugbear to him and he intended 

 to attack it vigorously in the Principles. " As far as 

 it goes I am delighted to be free from ' the immutability 

 of species ' and to be able on good grounds to accept evo- 

 lution. But it is absolutely uncertain how we are to ■/ 

 conceive of this latter. Therefore I say that the natural 

 system of classification is only to be explained by Descent, 

 but how this is to be explained no one knows. I regard 

 Descent as a fact, like gravitation, about which also we are 

 absolutely in the dark." His whole conception of the 

 world rebelled against " the crude materialism " which he 

 thought he found in Darwinism; "if my Principles do 

 not meet with the response I had expected, they have done 

 me good service in showing me that Darwinism as a whole 

 is entirely superfluous for any scheme of the final causes 

 of nature. A superfluous theory has received its sentence." 



He sought however to obtain some similar conception 

 of causes by his theory of " organ-forming matter," which 

 caused the external diversity of organs to appear dependent 

 upon their material differences of substance, a view which 

 had its origin in the researches alluded to above on the 

 dependence of bud-formation upon the assimilation activity 

 •of the leaves. By this a theoretical basis was gained for 



