100 THE MOST PRIMITIVE METAZOA 



comparative physiology and biochemistry of the lower Metazoa 

 and very little experimental work has been done on their 

 embryology. It is possible that these lines of research will help 

 in the elucidation of the relationships between the lower Metazoa. 

 It is also possible that the new information will indicate more 

 clearly that the Metazoa are polyphyletic. 



