ALGAE are a type of simple plant life and are found in a wide variety of modern environments. Those living in the sea are commonly known as "seaweeds." The many small, green to yellow-green, bushy objects placed throughout the Silurian reef diorama are meant to represent algae as reef dwellers. This reconstruction is highly interpretive. Fossil seaweeds like those pictured here are known from a few Silurian deposits, but they have not been found in actual reef rock in Wisconsin or Illinois.
Nevertheless, algae and microbial organisms that secrete calcium carbonate were present as binders in the Silurian reefs, as indicated by layered, crust-like growths around other fossils.