THE PROBLEM OF PATTERN 9 



basis of arrangement and order resulting from the inter- 

 action of the hypothetical protoplasmic entities, deter- 

 minants, pangenes, or whatever we choose to call 

 them, is not only more extremely speculative but fails 

 completely as a mechanistic hypothesis. To account 

 adequately in any such terms for the uniformity, defi- 

 niteness, and constancy of organismic pattern requires 

 the further postulation of something very closely resem- 

 bling the ordering and integrating principle of the 

 vitalists. And finally, even though we invoke the aid 

 of variation and natural selection at every step, as 

 Weismann has done, our increasing knowledge of the 

 facts of adaptation and of the amazing variety and 

 delicacy of regulatory response to environmental con- 

 ditions present always new difficulties to the pre- 

 formistic interpretation. 



Turning to the other mechanistic alternative, the 

 imposition of organismic pattern upon protoplasm 

 through its relations with the external world, it is clearly 

 necessary for any adequate conception first, that we 

 know something of the fundamental nature of organismic 

 pattern, and second, that we determine, experimentally 

 if possible, how such pattern originates in the relations 

 between protoplasm and its environment. One of the 

 most striking aspects of organismic pattern, to which 

 attention has already been called (see p. 8), viz., the 

 similarity as regards various of the more general features 

 in different protoplasms indicates that such pattern, at 

 least as regards these features, cannot be very closely 

 associated with the specific differences in the proto- 

 plasms of different species or groups and suggests the 

 possibility that it may be primarily quantitative in 



