on the Nilsen Plateau, and the Buckeye Tillite (140–308 m) in the Wisconsin Range and Ohio Range. The glacial beds are valley fill or occur as sheets. This is followed by the Misthound Coal Measures (150 m) in the Darwin Mountains and the Permian Weller Coal Measures (250 m) in South Victoria Land. A disconformity separates the Misthound Coal Measures from the overlying Ellis Formation (177 m), consisting of conglomerate, sandstone and siltstone. The Pyramid Erosion Surface separates the Mitschell Tillite and the Weller Coal Measures, which are overlain by the Feather Conglomerate (215 m) and the Triassic Lashly Formation (520 m). The Pagoda Tillite is overlain by the MacKellar Formation (140 m) of interbedded black shales and fine sandstones, the Lower Permian Fairchild Formation (220 m) arkosic sandstone, the Upper Permian Buckley Formation (750 m), the Middle-Lower Triassic Fremouw Formation (650 m), the Upper-Middle Triassic Falla Formation (530 m), and the Jurassic Prebble Formation (0–460 m) volcanic conglomerate, tuff and tuffaceous sandstone. Palæontology Body fossils The Aztec sandstone contains units bearing body fossils of fish: Phyllolepid placoderms, and thelodonts, abundant in fish beds, and conchostracans. The presence of Scoyenia ichnofacies implies freshwater. Also present are charred wood remnants and the plants Glossopteris and Haplostigma. The wood bears clear growth rings, indicating a seasonal environment, and is large enough to represent a temperate climate, though glacial just before Beacon deposition. Trace fossils Trace fossils are sparse below, but become common in the Hatherton Sandstone. They change from Skolithos-dominated facies to wide diversity and abundance, including vertical and horizontal burrows and huge arthropod trackways. The size of the arthropod tracks (less than 91 cm) is taken to imply that water must have been required for support. Fodinichnia: feeding burrows, probably of marine polychaetes, featuring evidence of rhythmic defecation. Narrow, sinuous, near-surface forms on flat bedding surfaces Longer, larger forms, reaching 13 cm across and 1 m in length. Walking trackways of arthropods (Repichnia). The presence of crawling traces in such well sorted sands is problematic. The arthropod trackways are thought to have been formed in shallow water, and supersaturated sand has a shallow angle of repose. Thus either a layer of organic matter, perhaps in the form of an algal slime, must have supported the sediment, or the sediment must have been partially dry. In the context of subaerial features such as raindrop marks and desiccation cracks on associated horizons, the