CHAPTER III 



THE ORIGIN OF AXIATE PATTERN IN NATURE 



AND EXPERIMENT 



It is a familiar fact that physiological axes persist 

 through certain agamic reproductive processes and are 

 therefore inherited by the individuals resulting from 

 such reproduction, but in at least many eggs the axiate 

 pattern apparently arises de noio during the growth of 

 the egg. Granting that axiate pattern in its simplest 

 form is a gradient pattern, as pointed out, we have at 

 present no grounds for believing that such pattern is 

 inherent in protoplasm, or that it can arise in protoplasm 

 apart from the action of environmental factors. Appar- 

 ently a differential exposure of the protoplasm to some 

 environmental factor or factors which affect its rate of 

 activity, i.e., which are primarily quantitative rather 

 than specific or qualitative in their action, is necessary 

 for the origination and establishment of an axial gradient 

 in protoplasm. Moreover, the quantitative nonspecific 

 character of . the gradient pattern suggests that its 

 origin is to be sought in the quantitative rather than in 

 the qualitative or specific aspects of the relations between 

 protoplasm and environment. In other words the 

 gradients must arise through the differential action of 

 environmental factors which affect primarily the rate 

 of general protoplasmic activity. 



THE ORIGIN OF POLARITY 



As regards the plants, Winkler ( 19006) and Kniep 

 (1907) showed that in certain algae, e.g., various species 



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