1. Spirillum bacteria of highly polluted water.
2. Sphaerotilus, bacteria from putrid water.
3. Wasserbluthe (Microcystis).
4. Clamydomonas, green alga.
5. Spirogyra, filamentous green alga.
6. Cladophora, branching green alga.
7. Rotifers (Rotatoria) from clear water.
8. Carchesium, bellshaped staked ciliate.
9. Diatoms mixed algae.
10. Water hyacinth, eichornia, rhizome t.s.