[4] Colonies grow on solid substrates and consist of individuals arranged in twisting rows.

[5] In the San Francisco Bay area, B. violaceus can be readily found on boat docks in the Richmond Marina.

Zooids are embedded in a transparent tunic and connected by a network of blood vessels that terminate in ampullae (small sac-like structures) at the periphery of the colony.

Colony color varies from bright orange to reddish or dull purple.

Because of chordates' close developmental relationship to vertebrates,[8] the regenerative processes in colonial ascidians are of great interest to researchers.