This collection of images was taken of protists found in a variety of freshwater ponds mostly in the vicinity of Konstanz in Germany. The majority of cells are from the moor pond illustrated - and this located to the west of Hegne (3 km northwest of Konstanz). It is about 100 metres in diameter and is surrounded by moorland. In turn this is surrounded by woodland. This protects this and other ponds from agriculture pollution. The small ponds in this area have a rich diversity of protozoa. The water is slightly brownish with a pH of 4 - 6. Ponds at other locations includes the "Muehlweiher" west of the village of Dettingen (5 km northwest of Konstanz). This is an artificial pond created to drive a millwheel but for the last 50 years the pond has been used for fish farming. The water has a pH of 6-7, is excellent for plankton and the outlet is often colonized with different species of suctoria. A further pond, "Ulmis Ried" (Ried = reed) was created artifically by a damming a brook near the University of Konstanz approximately 15 years ago. Some trees died and formed a habitat for birds and amphibia. Ulmis Ried is looked after by the Biology Department of the University at Konstanz. The bottom of the pond has a thick bed of black mud, it has a pH of 5-6 and supports many different water plants. Ulmis Ried is a good site to collect euglenids, chrysophytes, and anerobic ciliates (such as Metopus) which can be collected from the mud. Image of acidic pond by Martin Kreutz, Image copyright: Martin Kreutz, image used under license to MBL (micro*scope).