Pictish art appears on stones, metalwork and small objects of stone and bone. It uses a distinctive form of the general Celtic Early Medieval development of La Tène style with increasing influences from the Insular art of 7th and 8th century Ireland and Northumbria, and then Anglo-Saxon and Irish art as the Early Medieval period continues. The most conspicuous survivals are the many Pictish stones that are located all over Pictland, from Inverness to Lanarkshire. An illustrated catalogue of these stones was produced by J. Romilly Allen as part of "The Early Christian Monuments of Scotland", with lists of their symbols and patterns. The symbols and patterns consist of animals including the Pictish Beast, the "rectangle", the "mirror and comb", "double-disc and Z-rod" and the "crescent and V-rod", among many others. There are also bosses and lenses with pelta and spiral designs. The patterns are curvilinear with hatchings. The cross-slabs are carved with Pictish symbols, Insular-derived interlace and Christian imagery, though interpretation is often difficult due to wear and obscurity. Several of the Christian images carved on various stones, such as David the harpist, Daniel and the lion, or scenes of St Paul and St Anthony meeting in the desert, have been influenced by the Insular manuscript tradition.