Plate P12. 1, 2. Thalassiosira leptopus (Grunow) Hasle and Fryxell, Sample 172-1063D-2H-4, 123-123 cm, >25. 3-5. Thalassiosira nordenskioeldii Cleve, (3) Sample 172-1061A-1H-CC, >20; (4,5) Sample 172-1063D-4H-4, 53-54 cm, st. 6. Thalassiosira oestrupii (Ostenfeld) Proshkina-Lavrenko, Sample 172-1063D-3H-4, 43-44 cm, >25. Scale bars = 10 µm. Click on image for close-up.