ILARGUS a river of Rhaetia Secunda, flowing from west to east, and emptying itself into the Danube. (Pedo Albinov. Eleg. ad Liv. 386, where the common reading is Itargus; others read Isargus, and regard it as the same as the river Atagis (Ἄταγις) mentioned by Strabo, 4. p. 207, with Groskurd's note, vol. 1. p. 356.) It would, however, appear that Ilargus and Isargus were two different rivers, since in later writers we find, with a slight change, a river Ililara ( Vita S. Magni, 18), answering to the modern Iller, and another, Ysarche (Act. S. Cassiani, ap. Resch. Annal. Sabion. 4.7), the modern Eisach, which flows in a southern direction, and empties itself into the Athesis.
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