SPECIALIZATION AND ORGANIZATION. IQ 



exhausted then. Who is able to trace out the reproduc- 

 tive alternations and metamorphoses of such simple yet 

 strange forms as the Dicyemids and Orthonectids, 

 supposed by some, though probably erroneously, to 

 stand as an intermediate group between the Protozoa 

 and the Metazoa ? 



And when we descend to the Protozoa themselves, 

 we find the reproductive cycles specialized in ways as 

 varied as the forms of life. Then behind and under- 

 lying the whole of this reproductive work, from Proto- 

 phyte to Phanerogam, from Protozoa to man, are those 

 intensely interesting phenomena of caryokinesis, which 

 are at once the most varied and the most uniform ex- 

 pression of reproductive energy that modern research 

 has yet revealed. 



I need not dwell longer on this subject. We have 

 not found the beginning of reproductive work, nor can 

 we see an end either to its divisions or to the structural 

 unities and divergencies correlated therewith. 



We might now turn to nutrition and sketch the gen- 

 eral features of its specializations and coordinations ; 

 but we should only find the same principles illustrated 

 in new directions, and might get weary without getting 

 wiser. 



I will therefore at once try to bring the leading 

 thought to a focus, and then very briefly point out its 

 application. 



Division of labor is the principle underlying all or- 

 ganic as well as all social progress. The development 

 of the principle brings with it mutual dependence of 

 the working units ; and hence, every step in advance 

 leads necessarily to that closer integration of the units 



