A gelatinous, semifluid substance coated the fibrous tissue of these sponges, and from this tissue there escaped a steady trickle of water that, after carrying sustenance to each cell, was being expelled by a contracting movement. This jellylike substance disappears when the polyp dies, emitting ammonia as it rots.
Ha a szivacs elhal, eltűnik belőle az ammóniákot fejlesztő, rothadó, kocsonyás anyag, csak a rostos szövet marad meg, s rőt színű lesz.