PHYLUM PORIFERA 



flagellate canals, and in the same situation are to be found 

 developing embryos (em., em'.}. 



B.Psammoclema 



D.Pol*erion 



FIG. 35^/J. External form of various Sponges. A, Oscaria, an encrusting form, 

 with the upper surface raised up into a number of rounded prominences ; B, 

 Psammoclema, a ramifying subcylindrical Sponge ; C, Euspongia (toilet 

 sponge), a massive form with a broad base ; D, Poterion (Neptune's Cup), an 

 example of a complex Sponge assuming the fgrm of a vase. (After Vosmaer.) 



The simplest Sponges are vase-shaped or cylindrical in 

 form, either branched or unbranched, and, if branched, 



G 2 



