20 slides

1 - Intestinal bacteria (Escherichia coli) from putrid water
2 - Putrefactive bacteria (Spirillum) from sludge poor in oxygen
3 - Putrefactive bacteria (Sphaerotilus) bacteria, forming long chains with sheaths
4 - Sludge bacteria (Methanobacterium) causing sewer gas
5 - Sulphur bacteria (Thiocystis)
6 - Wasserbluthe (Microcystis), blue-green alga "blooming" in stagnant water
7 - Anabaena, blue green algae, in eutrophic water
8 - Spirogyra, filamentous green alga in nutrient-rich water
9 - Spirulina, corkscrew-shaped algae occurring in bitter seas
10 - Chlamydomonas, one-celled green alga in eutrophic water
11 - Cladophora, green alga with branching filaments from moderately polluted water
12 - Diatoms, mixed algae from scarcely polluted water
13 - Euglena, common green flagellates occurring in stagnant eutrophic water
14 - Ciliates, different species from nutrient-rich water
15 - Rotifers (Rotatoria), small animals from putrid water
16 - Tubifex, fresh water oligochaete, living in the sludge
17 - Carchesium, bell-shaped stalked ciliate from moderately polluted water
18 - Water mould (Saprolegnia), harmful to plants and animals
19 - Skin of fish injured by chemicals, t.s.
20 - Skin ulcer of an amphibian, t.s.