70 



COMPARATIVE ANATOMY. 



large divisions are therefore arranged in genealogical connection. 

 The extent to which each division is separated from its fellows 

 varies in each case. The relation of the various large divisions to 

 one another is seen in the subjoined tree. 



Vertebrata 



Mollnsca 



Arthropoda 



Braehiopoda 



Eehinodermata 



Vermes 



Coelenterata 



Protozoa 



The more exact limitation of the separate divisions, as well as the 

 reasons for the genealogical relations here merely indicated, will be 

 found in the special chapters. 



