Plate 3. Upper Miocene silicoflagellates. All specimens magnified 500× unless otherwise stated. 1. Bachmannocena quadrangula (Ehrenberg ex Haeckel), Sample 162-907B-11H-4, 109-110 cm. 2-4. Distephanus speculum speculum (Ehrenberg), same specimen from Sample 162-907B-12H-2, 109-110 cm (3, 4 are shown at high and low focus, respectively, both magnified at 1250×). 5. Distephanus xenus Bukry, Sample 162-982B-41X-1, 99-100 cm. 6. Dictyocha brevispina ausonia (Lemmermann), Sample 162-982B-24X-5, 99-100 cm. 7-12. Distephanus speculum minutus (Bachmann). (7, 8) Sample 162-907B-15H-1, 109-110 cm, same specimen at high and low focus; (9, 10) variety with equant spines, Sample 162-907B-10H-5, 117-118 cm, same specimen (10 magnified at 1250×); (11) five-sided variety, Sample 162-907B-10H-5, 117-118 cm; (12) seven-sided variety, Sample 162-907B-10H-5, 117-118 cm. 13. Bachmannocena diodon borderlandensis Bukry, Sample 162-982B-21H-6, 99-100 cm. 14. Bachmannocena diodon nodosa (Bukry), Sample 162-907B-17H-2, 109-110 cm. 15. Bachmannocena sp. cf. B. diodon borderlandensis, Sample 162-982B-41X-1, 99-100 cm. 16. Bachmannocena diodon diodon (Ehrenberg), Sample 162-907B-17H-1, 109-110 cm. 17-20. Bachmannocena circulus apiculata (Lemmermann). (17) Sample 162-907B-15H-3, 109-110 cm; (18, 20) Sample 162-982B-44X-3, 99-100 cm; (19) Sample 162-982B-39X-3, 99-100 cm.