This photograph was taken with a X25 Leitz water immersion lens. The legs are in fact cirri which are modified cilia and help the protozoan to move over the substrate. This photomicrograph is of the alga Pediastrum and belongs to the chlorophyceae. The colony is plate shaped and the outer cells have two spikes each. Each cell also contains a pyrenoid which is a storage organ for starch.
Reproduction can be either asexual or sexual.
All the cells in the colony can form zoospores and are then released into the water where they swim off and form new colonies. This photograph is of the filamentous alga Zygnema. This filamentous alga can be easily recognised by the two star shaped chloroplast that are found in each cell. The bridge like connection between the two chloroplasts is the cell nucleus Figure 6. This high power photograph is of the cyanobacterium called Nostoc.