Published online by Cambridge University Press: 11 May 2009
The larva of the compound ascidian Polyclinum aurantium Milne Edwards (1842) has been described by Berrill (1950), and his figures and description indicate a dissociation between the ampullae and epidermal vesicles. A reexamination of the larvae of this form shows that this is a false disjunction. This is most evident in the younger stages. Berrill describes (p. 46) a ring of eight ampullae, in the larva of Polyclinum, surrounding the anterior tip of the trunk, and ‘numerous epidermal vesicles growing out or detached from two long strands reflected posteriorly” (p. 89).