The Cornovii is a hypothetical name for a tribe presumed to have been part of the Dumnonii, a Celtic tribe inhabiting the south-west peninsula of Great Britain, during some part of the Iron Age, Roman and post-Roman periods. The Cornovii are supposed to have lived at the western end of the peninsula, in the area now known as Cornwall, and if the tribal name were correct it would be the ultimate source of the name of that present-day county. The existence of this sub-tribe, clan or sept, is not mentioned in Ptolemy's 2nd-century Geography, as are many of the other Iron Age tribes in Britain. It has been inferred solely on the basis of a place-name listed in the Ravenna Cosmography of c. 700 CE as purocoronavis, which is considered to be a scribal error for durocornavis (or durocornovium), interpreted as meaning "the fortress of the Cornovii". Etymology According to Ptolemy, there were two other tribes known as the Cornovii, one in the Midlands and another in the far north. It is on this basis that the name of this putative ancestor-tribe of Cornwall is inferred. Although the Brittonic name is clearly derived from the word *cornu-, which means "horn", opinions diverge over whether or not this refers to the shape of the land. Considering that Cornwall is at the end of a long tapering peninsula, many scholars have adopted this derivation for the south-western Cornovii. For instance, Graham Webster in The Cornovii (1991), which is primarily about the Midlands tribe, states that the horn derivation could apply as long as the geography was apparent, as it might have been to Roman surveyors in the first century, and Victor Watts in the Cambridge Dictionary of English Place-names (2010) interprets the name *Cornowii, a different spelling for latinised Cornovii, as "the people of the horn". Malcolm Todd, in The South West to AD 1000 (1987), discusses other etymologies that have been put forward, such as the name being a reference to dwellers in promontory forts, and an explanation hypothesised by Ann Ross in 1967 that the tribal names may be totemic cult-names referring to a "horned god" cult followed by the tribes, which Todd says may be cognate with the Gaulish Cernunnos or the unnamed horned god of the Brigantes. In an attempt to explain the same tribal name being used in the Midlands and Cornwall, the historian John Morris put