Plate P2. Scale bar = 10 µm. 1. Discoaster loeblichii (Sample 189-1172A-10H-3, 15 cm) (phase-contrast light [Ph]). 2, 3. Discoaster surculus (Sample 189-1172A-10H-3, 15 cm); (2) Ph; (3) differential-interference contrast light (DIC). 4. Discoaster triradiatus (Sample 189-1172A-10H-3, 117 cm) (Ph). 5. Discoaster hamatus (Sample 189-1172A-20H-7, 15 cm) (Ph). 6, 7. Discoaster quinqueramus (6) Sample 1172A-12H-6, 15 cm (Ph); (7) Sample 189-1172A-10H-3, 15 cm (Ph). 8. Discoaster berggrenii? (Sample 189-1172A-10H-3, 15 cm) (Ph). 9. Amaurolithus primus (Sample 189-1172A-12H-5, 15 cm) (Ph). 10. Amaurolithus delicatus (Sample 189-1170A-15H-3, 60 cm) (DIC). 11. Amaurolithus ninae (Sample 189-1172A-11H-7, 15 cm) (Ph). 12. Amaurolithus triconiculatus (Sample 189-1172A-11H-7, 15 cm) (Ph).