286 The American Naturalist. [April, 



no question regarding the position occupied by Schwendener 

 as leading the modern school in Germany. 



In reference to the influence of Sachs on the leading text 

 books of the present day, this is even more evident. While 

 many other men of eminence in this field have contributed 

 the results of their labors, not only by original research but 

 also by writing text books, it is as yet true that they differ but 

 little in methods of work or in the ivmiIh obtained, from those 

 general methods and principles which were fir.-l disseminated 

 from the laboratory of Wiirzburg from the pen of the most 

 popular and brilliant writer the world has yet produced in 

 this special field of investigation. 



In conclusion, therefore, it remains only to contrast once 

 more, briefly the leading features of both schools. 



In the one there is a tendency to put mere speculation and 

 fanciful conjecture in the place of theory. Rather than to 

 admit our present ignorance and weakness, effects are some- 

 times referred to causes which cannot be proven in harmony 

 with those laws of nature which are recognized in other 

 departments of natural science. 



In the other the principal lines of research are in the direc- 

 tion of mechanical questions, but at the same time there is a 

 clear and distinct recognition of our present limitations and 

 of the relative value of such questions in the ultimate dc U i mi- 

 nation of the action of forces which are yet beyond our reach. 

 To the botanists of the present day and the future it remains 

 to verify and reject, choosing the true and rejecting the false 

 from both lines of research, till the decisions of the future 

 shall make clear how much of error yet clings to the old 

 school and the new. 



