This yellow-brown seaweed grows in dense masses on the mid shore of sheltered rocky shores. It is identifiable by the egg-shaped air bladders that give it its name.

Look for Water avens in damp habitats, such as riversides, wet woodlands and wet meadows. It has nodding, purple-and-orange flowers that hang on delicate, purple stems.

This bumpy shell lives up to its name and lives partly buried in the seabed along the west coast of Great Britain.