Deo Mapono (at Ainstable, near Armthwaite, Cumberland), Apollini Mapono (at Hexham, in Northumberland). Mogons ( = Apollo) was worshipped in Britain by Vangiones in the Roman army, as may be seen from the formula Deo Mogonti, which occurs on inscriptions at Plumpton Wall (Old Penrith), Netherby, and Risingham. The god Silvanus, too, who was widely worshipped in Spain, in Cisalpine Gaul, in the neighbourhood of the Rhine, in the south of Gaul, and in central Europe, is also mentioned in Britain on about sixteen inscriptions. On one at Housesteads he is identified with Cocidius by a certain prefect of a cohort of Tungrians. This wide worship of Silvanus in the Celtic world is very suggestive of the form into which the early tree-worship of the Celts had developed.
The name Maponos, identical as it is with the Welsh Mabon, suggests that Modron, who is represented in Welsh legend as his mother, was an ancient British goddess, whose name in Roman times would be Mātrŏna, a derivative of the root matr- (mother). This very name, it may be noted, is the original of that of the river Marne. Some of the river-names of Wales appear to be formations of this type, and the suggestion naturally arises that they also were names of goddesses. For example, the name Aeron, in Cardiganshire, may stand for Agrŏna, the goddess of war. Tarannon may have meant the goddess of thunder. The river Dee, Dēva (Welsh Dyfr-dwy), means simply the goddess. The two streams, Dwyfor and Dwyfach, near Criccieth in Carnarvonshire, probably mean ‘the great goddess’ and ‘the little goddess’ respectively. The name Ieithon, a stream in Radnorshire, may mean ‘the goddess of speech,’ while ‘Crawnon,’ in Breconshire, may mean ‘the goddess of storage.’ The river-names of Celtic countries might on investigation yield very valuable information as to local deities.
7. The Transrhenane and Danubian districts.—In these wide zones the task of separating Celtic and Germanic deities is well nigh impossible, but its very difficulty suggests that to both peoples the popular substratum of religion had far
