Sponges

 


Phylum: Porifera
(Most sponges are difficult to classify on external appearance and require microscopic examination of the spicules to provide accurate identification).

Sponges form many different shapes from tall finger like sponges and flat sheets such as those in this picture, to encrusting forms that form a layer of the surface of rocks and other objects. Even the same species can have different forms depending on where it grows.All sponges are arranged in a way that maximises the flow of water around them.