4.3" Rare Fossil Peanut Worm (Lecthaylus) Plate - Illinois

This is a plate of rare peanut worm (Lecthaylus gregarius) fossils, collected from the Lockport Shale near Blue Island, Illinois. These fossils are Middle Silurian in age, or roughly 430 million years old. The longest worm measurement is 2" and the shale measures 4.3 x 3.3".