Abstract. In this paper, the third of a series of four, 25 new species are described from the Neogene sediments of the Southern Ocean: six spumellarians (Actinomma telarania, Hexacontium? cooki, Lonchosphaera shackletoni, Joergensenium pseudodictyocha, Cryptolarnacium pauliani and Spongoplegma dentifrangibula) and nineteen nassellarians (Arachnocorallium cerebellum, A. stilla, A.? pyroensis, Amphiplecta? satoshii, Antarctissa kjelli, Lithomelissa celsagula, Botryopera piperata, B. vavato, Lophophaena? neuma, L.? globeacuculla, L. pileata, L. amictoria, Pseudodictyophimus ignatius, Spongomelissa? bipatens, Ceratocyrtis? arthuri, C.? ringisstola, Phormostichoartus ashbyi, Ceratospyris clinamen and Dorcadospyris kennetti).