376 FIIYSIOLOGICAL DEVELOPMENT. 



going paragraphs suggest how this necessary correlation ig 

 brought about. For a great part of the physiological union 

 that accompanies the physiological specialization, there 

 appears to be a sufficient cause in the process of direct equili- 

 bration ; and indirect equilibration may be fairly presumed a 

 DiiSicieut CiJ.use for tha-t which, re.inaip^. 



