THE GEOLOGICAL EVIDENCES 



living organisms represented are the only types 

 known to nature, is no longer applicable in the 

 sense it was intended by its illustrious promulgator, 

 and it is vain to plead the individuality or want 

 of convergence of animal groups. 



But let us press the inquiry still further, and 



Different types of tail - structure. 1. Homocercal (modern form). 

 2. Heterocercal (ancient form). 3. Diphycercal (primitive form). 



within a narrower sphere. I have thus far treated 

 of the relations of the different higher groups 

 of animals, the limitations of which may not be 

 very clear to the non-scientific mind. But where, 

 the skeptical mind may ask, are the proofs of 





