Page 2 - at-winter-microscopy-pdf

The Algae

Three basic types of algae occur in my
samples, small unicellular, slightly larger
multicellular or colonial species and
filamentous species.

Among the unicellular species members of
the genus:

Closterium are usually quite common. They
are described as having crescent-shaped
cells, rarely straight, with a conspicuous
vacuole at each pole containing gypsum
granules. Each cell contains two
chloroplasts separated by a central area
containing the cell’s nucleus (Figs. 3, 5).
The other spheres occurring in the
chloroplasts, especially obvious in Fig. 5,
top are pyrenoids. These are protein bodies
around which starch collects and likely serve
as food-storage structures. The cell wall
may be smooth or grooved (Fig. 4.).

Fig. 3. Variously shaped Closterium spp.