A PHYSIOLOGICAL CHART 



257 



beyond practical application. If the student's attention can be 

 first directed to a few of the main features he will soon find himself 

 easily working through the other related reactions. 



The chart is built up before the student from da}^ to da}', as 

 the lectures or recitations in the class room present the different 

 physiological processes. This method affords an opportunity to 

 place each new subject studied in its proper relation to the other 

 subjects that ha\ e already been treated and keeps the mind con- 

 stantly on the lookout for the new reactions and new relations 

 which are to follow. By the time the student has completed the 

 phj'siological life-cycle he should be able to grasp the delicate 

 adjustment of the plant mechanism in a rather satisfactory way. 



In order that physiological nomenclature may be entirely con- 

 sistant with the chemical and physical reactions found in the liv- 

 ing plant protoplasm, such words as implj' a purpose, or a definite 

 and direct relation to a foreseen end have been avoided, it can 

 not be emphasized too strongly that such words as storage, reserve, 

 translocation, waste products, and the like, often give an uncon- 

 scious if not a conscious impression that there is a mysterious some- 

 thing in the life of the plant, which directs all reactions to a 

 purposeful end. On the other hand such words and phrases as 

 accumulation, transfer, and by-products avoid this impression 

 and emphasize the true chemical and physical nature of the 

 processes. 



No claim can be made that this chart is complete, but it is merely 

 an attempt to suggest a method of teaching which has a rather 

 broad application. The teacher of course can modifj' the chart to 

 fit cases of partial and complete parasitism, • and saprophytism 

 as well as the corresponding host relations. Only the barest out- 

 lines of physiology can^ be given, viz: the process, its essentials, 

 products, and by-products. The various conditions both without 

 and within the plant which control these processes can of course 

 not be indicated on a diagram of this size. 



