1-5. Helotholus vema. (1, 2) Two images of same specimen taken in apical view at different focal planes. (1) Focus on upper wall of thorax; (2) Focus on internal ring structure. DSDP 29-278-8-2, 10-12 cm; (3) View of specimen looking upward from base of thorax into shell. DSDP 29-278-8-6, 0-2 cm; (4) Diagrammatic illustration of upper lattice-wall of thorax, viewed from below and looking towards cephalis. The four shaded dots indicate where vertical bars from internal ring structure are attached; (5) Diagrammatic illustration of internal ring structure in cut-away view, looking obliquely downwards towards open base of thorax. Lattice-wall pores of thorax not drawn in. 6-8. Actinomma golownini; (6) DSDP 29-278-14, CC; (7) DSDP29-278-13-5, 56-59 cm; (8) DSDP 28-266-10-3, 147-149 cm. 9. Lychnocanium grande. Photo-composite of two images of same specimen taken at different focal planes. Sample 113-689B-3H-3, 56 cm.