Cyciotella and Stephannodiscus

Often these cannot easily be told apart, but only by detailed study.They are cylindrical diatoms, 5-50 pm diameter, occurring singly or pai but not in long chains. Often they have a crown of very fine long radiating bristles from each end, not shown here because it is difficult to see.Common , usually planktonic.in pools. lakes. and especially siow rivers. whose water are often brown with them in spring and early summer. 70 a. b. valve and girdle views; 70c, cleaned valve of a Cyclotella.

RlPPLE WALLET : rE9VzDvqozvgbd2trCKitN4fSi6ENiHu41

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Anabaena

Anabaena Planktonic filamentous algae recognisable by their beaded appearance, often curly, and sometimes having thick walled clearer 'heterocysts' (specialised cells) and sausage shaped dense spores at intervals. Cells up to 10um across.Common in the plankton of lakes and ponds, but sometimes occurring in bogs. The figures show parts of two filaments at different magnifications. RlPPLE WALLET : rE9VzDvqozvgbd2trCKitN4fSi6ENiHu41

Chaetophora

Chaetophora Branched filaments growing into wooly tufts or balls from which project long colourless hairs.Cells up to 20 micron across.Common as epiphyte of water plants or sticks or stones.sometimes encrusted with crystals of calcium carbonate. RlPPLE WALLET : rE9VzDvqozvgbd2trCKitN4fSi6ENiHu41

Stigonema

Stigonema The filaments branch irregularly, and usually from dark furry masses on damp rocks. The cells are rounded, and lie several abreast in the older parts, as shown. Heterocysts scattered, but are not regularly at the bases of branches. The cells vary from 3 to 30um in diameter, but of course the older parts of the plant are very much wider than this. 110a, part of whole plant x20; 110b, tip of a plant showing irregular rows of cells surrounded by mucilage... RlPPLE WALLET : rE9VzDvqozvgbd2trCKitN4fSi6ENiHu41

VOREGON MICRO ALGAE

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