of varying size, but also much larger specimens such as ichthyosaurs and plesiosaurs. Although these rocks were formed under water, the discovery of fossil wood, land-dwelling animals, and a pterosaur suggest that dry land was close by. Middle Lias Laid down during the Pliensbachian to Early Toarcian in a shallower marine environment that was subjected to much more turbulent weather conditions, the sediments of the middle Lias are not as muddy as those in the lower Lias, and are much nearer to silt and sand. These sands are thought to have come from the islands that now form part of Cornwall and South Wales. Again, inland exposure is poor, although the middle Lias is visible along the spring line of the hills that surround the Marshwood Vale. The cliffs either side of Eype and the coastal stretch between Thorncombe and Watton Cliff provide the best view. The base of the middle Lias is composed of three thick layers of calcareous sandstone beds separated by marls. These resistant bands form massive buttresses along the sea cliffs, and where eroded, boulder aprons on the foreshore. Above these three layers is the Eype clay, which was probably deposited in deeper, calmer waters. Ammonites found in this layer had apparently been attacked by larger crustaceans. The fossilised remains of large numbers of brittle stars, found towards the end of this deposition, indicate that they were rapidly covered. Theories put forward suggest a great storm or tidal wave was the cause, and indeed many of the remains appear to have been swept along the sediment, some losing limbs on the way. This particular section of the lias is appropriately known as the "starfish bed". The succeeding layers of Downcliffe and Thorncombe sands also appear to have been deposited in a periodically stormy environment where silts and sands dominate. Pebbles and cobbles are found here, encrusted with fossilised animals, which suggest that some of the sediments were already lithified; also, some evidence exists of localised fault activity. The last layer in the middle Lias is the Marlstone Rock bed. Upper Lias The lowest part of the upper Lias, the Beacon Limestone Formation, formed during the Pliensbachian to Toarcian, around 182 Mya. It is known as the junction bed and despite representing 3 million years of deposition, is only 0.6 to 1.5 m thick, where it can be seen at Eype Mouth. In Yorkshire, the equivalent stratum