SPONGES 



m.osc. 



A 



FIG. 20. 



A, Enryplegina auricularc, F.E.S. B, Poliopojon amadou, W. Tli. C, Caulophacus elegans, 

 F.E.S. All three after Schulze. A, reduced ^ ; B, $ ; C, natural size. 



unique amongst sponges in possessing an inhalant tube of this kind, 

 doubtless advantageous to the sponge, living as it does partially 

 buried in the soft ooze. 



Having considered the chief types of form which the sponge 



FIG. 21. 

 Farrea facunda, O.S. (After Agassiz.) 



