1*92.] Tioo Schools of Plant Physiology. 21 1 



THE TWO SCHOOLS OF PLANT PHYSIOLOGY AS AT 



PRESENT EXISTING IN GERMAN Y 



AND ENGLAND. 1 



tific schools of Europe in advance even of the same depa 

 ment of animal life. It is also well-known that in Gonna 

 the three most prominent men who have contributed to t 

 result are Naegeli, Sachs and Schwendener. 



The expression "Two Schools of Plant Physiology " is o 

 however, which requires some explanation, and possib 

 defense. It implies that the various conflicting theories whi 

 are at present occupying the botanical world maybe tra< 

 back to two distinct sources, which, if true, is a fact not 

 universally known or admitted. 



All scientific students whose knowledge of botany extol 

 as far as a mere superficial acquaintance with the ordinary U 

 books, are more or less familiar with the position occupied 

 Sachs. His text book may be said to be the first general t« 

 book on the science of the plant kingdom : that is, the fi 

 reckoning from that time when our knowledge of the p] 

 nomena occurring in this kingdom and of the laws govern 1 

 them was considered sufficient to warrant the expression 

 ence of the vegetable kingdom." The various text books 

 general botany written before this time are now considered 

 little worth except as historical records. It is partly owing 

 this fact of priority that all our later text books bear 

 strongly the impress of Sachs' personal teaching. His na: 

 is constantly repeated in connection with the principles whi 

 he advocates, whether these principles owe their discovery 

 him or his predecessors. It is, therefore, impossible to read a 

 of the ordinary text books without becoming somewhat fan 

 iar with the ideas and theories advocated by Sachs. 



iu„«,i k-fc— ♦».- m ~H„a of the American Society of Naturalists, Phila., Dec. 



