| | The Sponges (Phylum Porifera) |
 | | Leuconoid sponges tend to live in large groups with each individual sponge having its own osculum, however the borders between individual sponges are often hard to define and the sponge may act more like a large communal organism. |
| | Sperm is released into the canals and is then pumped out of the sponge through the osculum where it is likely to be drawn into the canal system of another sponge. |
| | Here incoming sperm of the same species are trapped by the choanocytes which then loose their flagellum and collar and migrate through the mesohyl to the ovocyte, a cell generating ova, where the sperm are transferred to the ova, assuming this is a sponge in its female form. |
| www.earthlife.net /inverts/porifera.html (2036 words) |
