BRACHIOPODS are relatively rare animals today and live only in seawater. They were much more abundant in seas of the Silurian Period. Brachiopods have a shell made of two halves. Each half of the brachiopod shell has a slightly different shape (figures 10a - 10d). Brachiopods feed by filtering tiny food particles from seawater. Most of the space inside the brachiopod shell is occupied by a special organ that acts as a water pumping and filtering device. Brachiopods do not move very much. Most are held to the bottom by a stalk (reconstructed in figure 10b). Some Silurian brachiopods lacked a stalk, had a flattened shell form (figure 3b), and rested freely on the seafloor.

At least 43 species of brachiopods represent the most diverse group of dwellers in the Silurian reefs of Wisconsin. The ten species shown above can be found in the Silurian reef diorama.

© 1997, Milwaukee Public Museum, Inc.