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of the bundle and not to our knowledge of its structure. This 

 sounds like mere quibbling over the meaning of words: so it is 

 introduced to show that a word originally applied to a division 

 of knowledge is now applied to certain features of a plant. The 

 same thing is true of physiology, of pathology, of various other 

 -ologies, not merely in the general field of botany but in other 

 sciences as well. 



To revert to the original subject, plant ecology may be defined 

 as the accumulation and organization of knowledge concerning 

 the correlation between the plant and its normal environment. 

 It now becomes difficult to divert the word from the meaning 

 given here into a concrete application as has been done so suc- 

 cessfully with morphology and physiology, because the subject 

 is based not on the plant alone, but on the plant and its environ- 

 ment together. Nevertheless, the attempt is frequently made. 



A botanist announces that he is studying the ecology of Smith's 

 Bog. Narrowed down to an exact statement by careful question- 

 ing, he admits that Smith's Bog has no ecology, that he is really 

 interested in the environmental relations of the plants there, 

 and that he discovers these relations, at least in part, by observa- 

 tions on their form and behavior. Undoubtedly the original 

 statement has brevity and is clear in its meaning, but it is im- 

 possible to include consistently any measurable or visible process 

 or structure in a plant exclusively under the term ecology. 



Two common expressions of this correlation between plant 

 and environment are found, as just stated, in the structure and 

 behavior of the plant. They must be studied by the methods 

 of morphology and physiology, they must be described in the 

 same terms used in morphology and physiology, yet the result 

 of the study is neither: they deal with the structure and behavior 

 of the plant, the result deals with the correlation between its 

 structure and behavior and the environment. The elongation 

 of the dandelion scape is a study in physiology, the structure and 

 development of the pappus a study in morphology, the dissemi- 

 nation of the dandelion a study in ecology. But since the ob- 

 servable effect of the interrelation of plant and environment is 

 frequently termed the morphology or physiology of the plant, 



