Bells for shepherding were expanded from the fertile crescent to Celtic, Carthaginian, Greek and Roman cultures. The earliest depictions of bells used for livestock in Britain appear on Pictish carved stones of the seventh to ninth centuries AD at Eassie, Angus and Fowlis Wester, Perthshire. Small iron bells of eighth- or ninth-century date, argued to be for cow or sheep, have been excavated from upland farm settlements at Crummack Dale and Gauber High Pasture in the Yorkshire Dales. An early depiction of a bellwether, the leading sheep of a flock, on whose neck a bell is hung, is in the Carolingian Stuttgart Psalter of the ninth century.