018 



ZOOLOGY 



SKCT. xiri 



In accordance with these conchisions the mutual relationships 

 of the phyla may be expressed in a diagrammatic form as 

 follows : — 



CHORDATA 



ARTHROPODA 

 MOLLUSCA 



MOLLUSCOIDA 

 TROCHELMINTHES 



rJEM/»THELMINTHES 



PLATYHELMINTHES\\ 



PROTOZOA 



Fig. 1 238.— Diagram illustrating the Mutual Relationships of the Phyla. 



