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organism. Occasionally, men in other fields of scientific work 

 attempted to solve some of the riddles of internal structure and 

 of physiology, but when they claimed admission to the ranks of 

 the botanists they were regarded as interlopers. Botany remained 

 for a time a virgin science, whose fecundity was revealed only 

 after union with physics and chemistry. From the time when 

 the botanist accepted the wider definition of his science, the 

 original path became divided at first into two, one of which 

 was directed toward the goal of physiology and the other 

 toward that of description. The latter trend of study led to 

 the necessity of common descriptive terms and of this necessity 

 was produced a morphology which culminated in classification 

 of plant parts by referring them to a "few elementary forms" 

 which forms, however, have a subjective reality only. This 

 is the idealistic morphology of Goethe, which in its time 

 served well its purpose. The " uniformity " of life discovered by 

 this morphology was a conception which prepared the mind for 

 the theory of descent, under which the variety of organic life 

 could be subsumed. It soon overleaped itself, however, and 

 became a mere formalism. The plasticity of nature was lost 

 sight of in the rigidity of subjective conceptions. So markedly 

 true has this been in some quarters, that the belief is held to with 

 a tenacity which would be more praiseworthy if exerted in a 

 better cause, that the sole business of morphology is to say that 

 things are so rather than how they come to be so. There are 

 certainly two ways of viewing an organ. We may look at it 

 simply as such, restricting our legitimate curiosity, and content- 

 ing ourselves with a mere description of it ; and then we may 

 search about in the limitless field of observation, and when we find 

 a similar form, seize upon it, and with a sigh of satisfaction, call it 

 a homology, thinking our task done, much as a curiosity collector 

 does in finding a particular object of his cupidity. Or we may 

 see in form a measurable expression of forces at work in the 

 living organism ; we may by experiment get at some more ade- 

 quate notion of its service in the economy of the plant ; we may 

 by searching find out why similar forms are produced in different 

 organisms and why in similar organisms, different structures are 



