CHAPTER VII 



A REVIEW OF THE FORMED CONSTITUENTS OF 



ORGANISMS 



In bringing together the materials for the present chapter 

 during the past fifteen years, the writer grouped these under 

 the title, "The stock-in-trade of plants and animals in relation 

 to their environment." And such seems in many ways a more 

 apt title than the heading given above. The contents of the 

 chapter will explain the line of investigation and argument 

 pursued. 



During the past half century, the steady spread of evolu- 

 tionary views has given rise to such expressions as "the pro- 

 duction of new characters," "the inheritance of acquired char- 

 acters," "definite or indefinite variation of species," "the 

 influence of the somatoplasm and of the germplasm in descent," 

 "the breeding true of unit characters," and many of kindred 

 import. Widely divergent and often conflicting views have 

 been put forth as to these and related questions of evolutionary 

 trend. 



In all such studies it has been either tacitly or openly de- 

 manded and accepted that many new and highly important 

 morphological or physiological characters appear in organisms, 

 as we ascend in the organic scale. But, granting an apparently 

 new character to have appeared, say in animals, in the form of 

 nerve cells and associated fibers, that are absent as such in 

 lower animals and in all plants, the question is still worth 

 looking into, as to how far and how fundamentally new char- 

 acters appear, and what is the sum total of the substances 

 or compounds that all living bodies tend to possess in common. 



This inquiry suggested itself to the writer about sixteen 

 years ago when he was endeavoring to secure accurate data as 

 to "acquired characters." The results seemed both striking and 



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