Phylum

Porifera (Sponges)

Cliona californiana. Photo: (c) als93, some rights reserved (CC BY)

Sponges, the members of the phylum Porifera (/pɒˈrɪfərə/; meaning “pore bearer”), are a basal Metazoa clade as sister of the Diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells.

— Wikipedia