Codium bursa is a green marine algae of medium size.

Codium bursa is a marine alga growing to 30 cm across.

It generally appears as a spongy sphere of utricles which at the surface form a cortex.

It is composed of loosely packed filaments which at the surface form a cortex of utricles which are single celled bladder-like or club-shaped structures.

[3] In the Atlantic from the Canary Islands to the British Isles,[4] where they perhaps are originating further south, since C. bursa is very persistent in drift.