These animals lived here over 400 million years ago, when the area that is now Lake Champlain Basin was part of a shallow tropical sea. The fossils were formed when shells, other hard parts of plants and animals or traces of the organisms, such as worm borings or animal tracks, were buried in limey mud. Over time, this mud cemented into limestone and shale.
Brachiopods are one of the easiest fossils to find.
A brachiopod shell looks like a clamshell, but has a distinct ridge running down the center. Brachiopods are still living today. Bryozoans are commonly called moss animals because of their appearance. Like coral, they are tiny soft-bodied animals that live in colonies. Each animal lives in its own chamber, giving the colony a honeycomb appearance.