Plate P1. Siliceous sponge spicules from ODP Leg 180. 1. Dichotriaene (315x) (Sample 180-111A-11R-1, 44.0-46.0 cm). 2. Anatriaene (315x) (Sample 180-1110A-1A-4, 94.0-96.0 cm). 3. Strongyle (315x) (Sample 180-1108B-1R-1, 10.0-12.0 cm). 4. Calthrops (500x) (Sample 180-1111A-11R-1, 44.0-46.0 cm). 5. Style (315x) (Sample 180-1110A-1H-2, 77.0-79.0 cm). 6. Sterraster (500x) (Sample 180-1111A-14R-3, 62.0-64.0 cm). 7. Spheraster (500x) (Sample 180-1109C-7H-4, 118.0-120.0 cm). 8. Acanthoxea (315x) (Sample 180-1108B-1R-2, 50.0-52.0 cm). 9. Oxea (315x) (Sample 180-1108B-1R-1, 10.0-12.0 cm). Scale bar 1 (for photos taken at 500x) = 25 µm; scale bar 2 (for photos taken at 315x) = 50 µm.

Plate P1. Siliceous sponge spicules from ODP Leg 180. 1. Dichotriaene (315x) (Sample 180-111A-11R-1, 44.0-46.0 cm). 2. Anatriaene (315x) (Sample 180-1110A-1A-4, 94.0-96.0 cm). 3. Strongyle (315x) (Sample 180-1108B-1R-1, 10.0-12.0 cm). 4. Calthrops (500x) (Sample 180-1111A-11R-1, 44.0-46.0 cm). 5. Style (315x) (Sample 180-1110A-1H-2, 77.0-79.0 cm). 6. Sterraster (500x) (Sample 180-1111A-14R-3, 62.0-64.0 cm). 7. Spheraster (500x) (Sample 180-1109C-7H-4, 118.0-120.0 cm). 8. Acanthoxea (315x) (Sample 180-1108B-1R-2, 50.0-52.0 cm). 9. Oxea (315x) (Sample 180-1108B-1R-1, 10.0-12.0 cm). Scale bar 1 (for photos taken at 500x) = 25 µm; scale bar 2 (for photos taken at 315x) = 50 µm.