The Roman Map of Britain Mutuantonis on the River Ouse, or on Margary 13

Mutuantonis var. Mantuantonis (R&C 69) next

    Midewinde 1237 is the old name of the Sussex Ouse. Ekwall  (ERN p 291 sub Midwin) thought it was 'no doubt English'.

    The Roman road system, while rather complicated to the east of the river, has two crossings with a Roman presence. The choices are South Malling (TQ4211) in the north by way of Margary 145, and to the south is Newhaven (TQ4401) by Margary 141. Beddingham (TQ4507) is at a crossing (M145) of the Glynde Reach, an eastern branch of the Ouse.

    Alternatively, Mutuantonis and the previous entry Nova may be unrelated road-wise to Anderetio Pevensey (R&C 67). The river Medway is Meduuuæian 764, and Medeuuæge 765-791. Maidstone  is Mæidesstana, Mæþan stan late 10^th. There are at least six villas at Maidstone: tq7556, tq7654, tq7557, tq7456, tq7555, and tq7752. Margary 13 (rochester-maidstone-hastings) runs through the center of the eastern group of iron-working sites in the Weald. Perhaps Novus was the old name of the river Brede, the Rother's was Lemana. 

Vicintiy of Lewes
PRIORY MOUNT; Lewes; Lewes; East Sussex TQ 4148 0950 Settlement, Roman NMRMIC-1413

MOUNT CABURN; GLYNDE; LEWES; EAST SUSSEX TQ 44 08 SETTLEMENT, Roman EHNMR-626248

RANSCOMBE CAMP; BEDDINGHAM; LEWES; EAST SUSSEX TQ 43 09 SETTLEMENT, Roman EHNMR-626257
RANSCOMBE HILL; SOUTH MALLING; BEDDINGHAM; LEWES; EAST SUSSEX TQ 43 08 SETTLEMENT, Roman EHNMR-626258

MALLING HILL; LEWES; LEWES; EAST SUSSEX TQ 42 11 FIELD SYSTEM, Roman; LYNCHET, Roman EHNMR-1319205

Newhaven
SOUTH ROAD/SOUTHWAY (RING ROAD); Newhaven; Lewes; East Sussex TQ 4450 0130 Settlement, Roman NMRMIC-2316
DACRE ROAD; Newhaven; Lewes; East Sussex TQ 445 013 Settlement, Roman NMRMIC-3052 Britannia : a journal of Romano-British and kindred studies 4/1973 321,
TIDEWAY SCHOOL (NEW HALL); Newhaven; Lewes; East Sussex TQ 44 01 Settlement, Roman NMRMIC-3085
TOWN CENTRE; Newhaven; Lewes; East Sussex TQ 44 01 Settlement, Roman NMRMIC-3086

CASTLE HILL; BURROW CLIFF; NEWHAVEN; LEWES; EAST SUSSEX TQ 44 00 SETTLEMENT, Roman EHNMR-626278

NEWHAVEN VILLA; NEWHAVEN; LEWES; EAST SUSSEX TQ 44 01 BUILDING, Roman EHNMR-626281

    The entry for Lewes in Imperial Gazetteer of England and Wales (1870-72)  by John Marius Wilson has "It is supposed also, from the discovery of numerous Roman coins, urns, rings, pateræ, and other Roman relics in and near it, as well as from other slight evidence, to have been the site of the Roman station Mutuantonis." I do not know Wilson's source or basis for the Lewes-Mutuantonis equivalence.
    In 1842 The Penny Cyclopaedia of the Society for the Diffusion of Useful Knowledge v.23 p.351 makes the same equivalence. 
    The choice was apparently based more on local needs - a significant un-named Roman site and an un-matched name in the Cosmography. This still happens on a regular basis.

   Dr Patrizia De Bernardo Stemple presents an interesting etymology for the Italian town of Modena, Ptolemy's Moutina Mut-ina 'the Foggy (town)'. Pokorny p.742f IE *meut- 'dunkel, Dunkelheit, Nebel (dark, darkness, fog) found in Middle  Irish as mothar ' thicket, thick mass' and Modern Irish as 'swamp, bog, marsh, fen'.
    The second element seems the same as that of Trisantonis. See ERN and CDEPN on the river-name Trent.