The general biology of Verruca stroemia (O.F. Muller) with some additional observation on penis development and moulting frequency in Balanus balanoides.

Abstract

First paragraph: This thesis is largely concerned with the biology of Verruca stroemia (O.F. Mulller), a common species of the sublittoral and near-littoral of the eastern Atlantic. A small animal even when fully grown, it is not very conspicuous, and there is very little information on its general biology. V. stroemia is the only easily accessible species of the genus, all others being found only in relatively deep water. Two features of its biology are of particular interest: first, although boreo-arctic in its distribution it is not, like some other species of similar geographical distribution, restricted to a single annual brood; secondly, the genus Verruca is a primitive one, in many respects more closely allied to the Lepadomorpha than to the Balanomorpha with which it is classified. Both these aspects of the species have been considered, the latter particularly with reference to feeding and cirral activity. The relation of the major nauplii release to the spring diatom outburst and the effects of desiccation have been investigated since these are important in the ecology of the species and there is much comparative data on both for other cirripedes.