SOCIAL "CROWNED HEADS." 137 



complex organisation (although we may not be able 

 to trace the intermediate stages or forms), either in 

 its individual development or in its tribal history, 

 yet we are warranted, in view of the general law 

 here indicated, in inferring that a series of grada- 

 tions in organic structure have really been passed 

 through before the complex organism under notice 

 could have arisen. This argument applies with 

 great force to the Rotifer a. Being so small, they 

 were originally classed with the Infusoria ; but on 

 closer examination of late years they were seen 

 to be very far removed from the Infusoria in 

 complexity of organisation, and were accordingly 

 re-classed. The gap between them, however, is 

 not filled up by known-existing forms showing 

 the several upward stages, although, when the 

 Hotifera form is observed, this gradation from 

 one to another is easily seen and traced. Yet, be- 

 cause we cannot find the missing links between 

 the Infusoria and the Rotifers, we are not justi- 

 fied in ignoring their existence in the ages that 

 have passed away. And we thus come to con- 

 template the Rotifers in a new light, having a 

 remote ancestry, and passing through severe strug- 



