Amasenus

AMASE´NUS a small river of Latium, still called the Amaseno, which rises in the Volscian mountains above Privernum, and descends from thence to the Pontine marshes, through which it finds its way to the sea, between Tarracina and the Circeian promontory. Before its course was artificially regulated it was, together with its confluent the Ufens, one of the chief agents in the formation of those marshes. Its name is not found in Pliny or Strabo, but is repeatedly mentioned by Virgil ( Aen. 7.684, 11.547). Servius, in his note on the former passage, erroneously places it near Anagnia, evidently misled by the expressions of Virgil. Vibius Sequester (p. 3) correctly says Amasenus Privernatium.
[E.H.B]