PLATE 4. Tesselacauda depressa Ross, 1951, from Section MME 75.5 m in Revision of the Early Ordovician (late Tremadocian; Stairsian) cheirurid trilobite Tesselacauda Ross, with species from the Great Basin, western USA

PLATE 4. Tesselacauda depressa Ross, 1951, from Section MME 75.5 m, Fillmore Formation (upper Tremadocian; Stairsian; Bearriverops loganensis Zone), Middle Mountain, Ibex area, Millard County, western Utah, USA. 1–3, 5, 7. Dorsal exoskeleton, SUI 147531, dorsal, ventral, left lateral, right lateral, and posterior views, x12. 4. Left librigena, SUI 147532, external view, x12. 6, 8. Right librigena, SUI 147533, ventrolateral and external views, x10. 9, 11, 13. Right librigena, SUI 147534, external, internal, and ventrolateral views, x12. 10. Right librigena, SUI 147535, external view, x10. 12, 14. Right librigena, SUI 147536, external and internal views, x12.