Plate P4. Transmitted light microphotographs of radiolarians from Holes 1218A, 1219A, and 1220A. Scale bar = 100 µm. 1. Artophormis barbadensis (Sample 199-1218A-24X-1, 65–67 cm), W28/0. 2–6. Artophormis gracilis group; (2) Sample 199-1220A-8H-1, 25–27 cm (F32/0), (3) Sample 199-1220A-7H-4, 125–127 cm (D23/2), (4) Sample 199-1218A-24X-7, 67–69 cm (R36/4), (5) Sample 199-1220A-6H-2, 125–127 cm (K44/4), (6) Sample 199-1220A-7H-3, 80–82 cm (Q26/4). 7–12. Thyrsocyrtis (Thyrsocyrtis) pinguisicoides O'Connor; (7) earlier form (Sample 199-1218A-25X-6, 30–32 cm), O23/1, (8) earlier form (Sample 199-1218A-25X-5, 120–122 cm), D35/0, (9) Sample 199-1220A-9H-1, 75–77 cm), O49/1, (10) Sample 199-1220A-9H-3, 75–77 cm (X48/1), (11) Sample 199-1220A-25X-4, 30–32 cm (U15/0), (12) Sample 199-1220A-9H-2, 25

Plate P4. Transmitted light microphotographs of radiolarians from Holes 1218A, 1219A, and 1220A. Scale bar = 100 µm. 1. Artophormis barbadensis (Sample 199-1218A-24X-1, 65–67 cm), W28/0. 2–6. Artophormis gracilis group; (2) Sample 199-1220A-8H-1, 25–27 cm (F32/0), (3) Sample 199-1220A-7H-4, 125–127 cm (D23/2), (4) Sample 199-1218A-24X-7, 67–69 cm (R36/4), (5) Sample 199-1220A-6H-2, 125–127 cm (K44/4), (6) Sample 199-1220A-7H-3, 80–82 cm (Q26/4). 7–12. Thyrsocyrtis (Thyrsocyrtis) pinguisicoides O'Connor; (7) earlier form (Sample 199-1218A-25X-6, 30–32 cm), O23/1, (8) earlier form (Sample 199-1218A-25X-5, 120–122 cm), D35/0, (9) Sample 199-1220A-9H-1, 75–77 cm), O49/1, (10) Sample 199-1220A-9H-3, 75–77 cm (X48/1), (11) Sample 199-1220A-25X-4, 30–32 cm (U15/0), (12) Sample 199-1220A-9H-2, 25–27 cm (V19/0).