Flagellates and swimming colonies
Volvox
Volvox (colonial green alga)
Hollow green balls made of hundreds to thousands of cells, rolling slowly through the water.
What to look for
- A sphere with many small green cells on the surface, each with two flagella.
- Daughter colonies inside the big ball, darker green.
- Rolls and rotates steadily rather than darting.
Size in the field
Large: visible as green specks to the naked eye; at 40× a colony fills a good part of the field.
Where to find it
Clean ponds and lakes, often in late spring and summer.
Clips 0
No clip of this group is on the site yet. The description above is enough to check your own observation.