8 THE ORIGIN OF THE NERVOUS SYSTEM 



inherent in protoplasm and a direct result of protoplasmic 

 constitution we should expect it to show a close relation 

 to the differences in constitution, e.g., some such relation 

 as that which exists between constitution and crystalline 

 form in the different haemoglobins (Reichert and Brown, 

 1 909) . While it is true that no two species or organisms 

 and even no two individuals are alike in all details, yet 

 the more general features of organismic pattern are 

 apparently to a large extent independent of specific 

 differences in protoplasmic constitution. As regards 

 the general plan of spatial arrangement of parts and 

 developmental sequence we find three general types of 

 organismic pattern of very wide occurrence, the com- 

 pletely radiate, in which the pattern is referable to a 

 center, the axiate or polar, in which it is referable to a 

 line, and the bilateral, in which it is referable to a plane. 

 At least most organisms show some one or some com- 

 bination of more than one of these patterns. Physio- 

 logically the most general feature of organismic pattern 

 appears to be that of dominance and subordination, of 

 controlling and being controlled. 



The attempts to discover terms in which a pre- 

 formistic conception of organismic pattern might be 

 formulated have been largely speculative and without 

 satisfactory results. For example, the conception of 

 organismic pattern in purely molecular terms, i.e., of the 

 organism as crystalloid, either as a whole or as a con- 

 geries of minute crystals similarly oriented, not only 

 fails to account for the facts, but finds its basis in remote 

 and apparently very superficial analogies, and certain 

 other suggestions along stereochemical lines are purely 

 speculative. The assumption of some other undetermined 



