252 THE EVOLUTION OF IiLiN. 



prising probably as many, if not more, distinct species tban 

 all the other classes of animals together. Unfortunate] y, 

 we lose by this the relationship which might otherwise 

 connect us with Termites, Ants, Bees, and other virtuous 

 members of the Articulate class. Among these insects aro 

 many well-known patterns of virtue, which the fable 

 writers of old classic times held up as examples for men. 

 In the civil and social arrangements of the Ants especially, 

 we meet w^th highly developed institutions which we may 

 even yet regard as instructive examples. But unfortu- 

 nately these highly civilized animals are not related to us. 



Our next task must now be, to enter in greater detail 

 into the vertebrate nature of Man, and to determine the 

 special position which he holds in the system of Verte- 

 brates. Here it is necessary to point out the most essen- 

 tial facts in the particular structure of the vertebrate 

 body ; for, otherwise, we shall be quite unable to enter 

 rightly into the difficult question of Ontogeny. The evolu- 

 tion of even the simplest and lowest Vertebrate from the 

 simple Gastrula is so complex a process, and is so difficult 

 to trace, that it is necessary to understand the principles 

 of the organization of the perfect \crtebrate, in order to 

 comprehend the principles of its evolution. But it is equally 

 important that in this brief anatomical description of the 

 vertebrate organism, we should stop only at the essential 

 facts, and leave all others untouched. Therefore, in giving 

 an ideal anatomical sketch of the main form of the Verte- 

 brate and its inner organization, I leave out all secondary 

 and non-essential circumstances, and confine mvself to 

 tthose most essential. 



Many parti cidars, which will probably appear highly 



