Plate P1. Illustrations of taxa, sample, and slide number. Scale bar = ~20 µm unless stated otherwise. Scanning electron microscope (SEM) photographs have varying scale bars. 1. Adnatosphaeridium multispinosum (Sample 189-1172D-15R-3, 40-42cm) (1). 2. Aio

Plate P1 (continued). 121, 122. Schematophora speciosa (Sample 189-1172A-39X-5, 55-57 cm) (1); scale bar = ~15 µm. 123. Selenopemphix nephroides (Sample 189-1172A-39X-5, 85-87 cm) (1). 124, 125. Senegalinium bicavatum (Sample 189-1172D-24R-5, 30-32 cm) (1). 126-129. Senoniasphaera inornata (126-128) Sample 189-1172D-24R-5, 12-14 cm (1); (129) Sample 189-1172D-24R-5, 36-38 cm (1). 130. Spinidinium luciae (Sample 189-1172A-39X-5, 55-57 cm) (1). 131, 132. Spinidinium macmurdoense; (131) Sample 189-1172A-39X-5, 105-107 cm (1); (132) Sample 189-1172A-39X-6, 105-107 cm (1).