128 ZOOLOGY SECT, m 



embedded in a mass of gelatinous substance, in which there are 

 also amoeboid zooids similar to the amoeboid wandering cells of 

 Sponges. 



But, while the Porifera are clearly Metazoa, and not Protozoa, 

 there is. some room for difference of opinion as regards their 

 relationships to the Ccelenterata, with which great phylum they 

 have been sometimes amalgamated. The reasons for and against 

 such an arrangement will be discussed in considering the 

 general relationships of the Ccelenterata. 



