| The velocity of the excurrent stream through the osculum may be several hundred times that at the level of the choanocytes. |
| The shell in all Circoporida exhibits a simple, excentric mouth, which corresponds to the main osculum of the central capsule. |
| Syconoid sponges tend to be larger than asconoids and have a tubular body with a single osculum. |
| Note the spicules covering the surface of the body, and the longer ones surrounding the osculum. |
| Osculum twice as broad as the central chamber, surrounded by a coronal of strong conical teeth, twice as long as its diameter. |
| The body wall is made stronger by a skeleton of inorganic spicules and hollow cells called porocytes that open to draw water through the porocytes into the atrium which is pushed out a main osculum. |
