ARCHIANNELIDS OF THE GENUS SACCOCIRRUS FROM SOUTHERN AFRICA

Summary

Specimens from South Africa belonging to the archiannelid genus Saccocirrus are described. An account is given of their habits and habitat, their external and internal anatomy, with special reference to the arrangement of the male and female organs. The problem of internal fertilization is discussed, and the maturation of the trochophore larva within the female body is described. Observations were made on larval dissemination by fragmentation during the breeding phase. Keys to the family Polygordiidae and the genus Saccocirrus are included. The specimens are assigned to a new species: Saccocirrus burchelli nov. sp. A description of the holotype and a diagnosis of the species are included.