Archimedes Bryozoan Helix Fossil
A very unusual and interesting fossil.
These fossils are from the Mississippian Period. They are about 324 million years old
Commonly referred to as an “Archimedes Screw” named after the ancient Greek Archimedes, the inventor of the water screw. This bryozoan looks like the water screw.
Bryozoans are microscopic aquatic invertebrates (zooids) and are filter feeders that live in colonies and form skeletal housing structures.
Archimedes was a fenestrate bryozoan colony. Fenestrate means they built lace like structures for their homes. The zooids lived in tubes in this structure which was attached to a screw shaped support. The fossil that you see is this support structure.
Classification: Kingdom Animalia
Mississippian Epoch: 324 million years old
Found: Indiana, USA.
Size: 10mm – 20mm