Plate P1. Note: all micrographs of coccoliths are of the proximal view unless otherwise noted as distal (D). All micrographs are from Sample 183-1139A-1R-CC. Pol = polarized electron micrograph, SEM = scanning electron micrograph. 1-4. Minute placoliths (of Gephyrocapsa?) that mimic Emiliania huxleyi as a result of etching during diagenesis that expands the central area and separates the outer shield elements (Pol). 5, 6. SEMs that demonstrate how etching has separated the radial shield elements along their outer margins, causing them to superficially resemble the "I" bars of Emiliania huxleyi. 7. Placolith (D) that exhibits overgrowth on the central area and, therefore, should not mimic Emiliania huxleyi in the light microscope. 8, 9. Pseudoemeliania lacunosa (Pol). 10, 11. Larger placoliths, possibly reticulofenestrids and/or gephyrocapsids, with heavily etched central areas and outer elements. These could mimic Pseudoemeliania lacunosa when viewed in the light microscope.

Plate P1. Note: all micrographs of coccoliths are of the proximal view unless otherwise noted as distal (D). All micrographs are from Sample 183-1139A-1R-CC. Pol = polarized electron micrograph, SEM = scanning electron micrograph. 1-4. Minute placoliths (of Gephyrocapsa?) that mimic Emiliania huxleyi as a result of etching during diagenesis that expands the central area and separates the outer shield elements (Pol). 5, 6. SEMs that demonstrate how etching has separated the radial shield elements along their outer margins, causing them to superficially resemble the "I" bars of Emiliania huxleyi. 7. Placolith (D) that exhibits overgrowth on the central area and, therefore, should not mimic Emiliania huxleyi in the light microscope. 8, 9. Pseudoemeliania lacunosa (Pol). 10, 11. Larger placoliths, possibly reticulofenestrids and/or gephyrocapsids, with heavily etched central areas and outer elements. These could mimic Pseudoemeliania lacunosa when viewed in the light microscope.