THE IDENTIFICATION OF THE NAUPLII OF SOME SOUTH AFRICAN BARNACLES WITH NOTES ON THEIR LIFE HISTORIES

Abstract

Preliminary investigations of the life history of seven species of sessile cirripede found round the Cape Peninsula, South Africa, have been made. The species studied are Balanus algicola Pilsbry, B. trigonus Darwin, B. maxillaris Gron., B. amphitrite Darwin var. denticulata Broch, Octomeris angulosa Sow., Tetraclita serrata Darwin and Chthamalus dentatus Krauss.

Routine observations were carried out on the reproduction of each species, on the presence of nauplii in the plankton and on the settlement of cyprids on experimental plates kept in Cape Town docks.

Information regarding each species is given together with diagrams of the naupliar stages, the setation formula, and a short description of salient points in recognition.

Special attention is drawn to a species of Hemioniscus parasitic in B. algicola and Chthamalus dentatus, and to the occurrence of various morphological types of B. amphitrite var. denticulata.