SOLO´NIUS AGER(Σολώνιον, Plut.), was the name given to a district or tract in the plain of Latium, which appears to have bordered on the territories of Ostia, Ardea, and Lanuvium. But there is some difficulty in determining its precise situation or limits. Cicero in a passage in which he speaks of a prodigy that happened to the infant Roscius, places it in Solonio, qui est campus agri Lanuvini ( de Div. 1.36); but there are some reasons to suspect the last words to be an interpolation. On the other hand, Livy speaks of the Antiates as making incursions in agrum Ostiensem, Ardeatem, Solonium(8.12). Plutarch mentions that Marius retired to a villa that he possessed there, when he was expelled from Rome in B.C. 88; and from thence repaired to Ostia. (Plut. Mar. 35.) But the most distinct indication of its locality is afforded by a passage of Festus ( s. v. Pomonal, p. 250), where he tells us Pomonal est in agro Solonio, via Ostiensi, ad duodecimum lapidem, diverticulo a miliario octavo.It is thence evident that the ager Soloniusextended westward as far as the Via Ostiensis, and probably the whole tract bordering on the territories of Ostia, Laurentum, and Ardea, was known by this name. It may well therefore have extended to the neighbourhood of Lanuvium also. Cicero tells us that it abounded in snakes. ( De Div. 2.31.) It appears from one of his letters that he had a villa there, as well as Marius, to which he talks of retiring in order to avoid contention at Rome ( ad Att. 2.3).
The origin of the name is unknown; it may probably have been derived from some extinct town of the name; but no trace of such is found. Dionysius, indeed, speaks of an Etruscancity of Solonium, from whence the Lucumo came to the assistance of Romulus (Dionys. 2.37); but the name is in all probability corrupt, and, at all events, cannot afford any explanation of the Latindistrict of the name.
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