ILLYRICA, (anc. geog.) a country extending from the Adriatic to Pannonia. Its boundaries are variously assigned. Pliny makes it extend in length from the river Arfia to the Drinius, thus including Liburnia to the west, and Dalmatia to the east; which is also the opinion of Ptolemy, who settles its limits from mount Scardus and the Upper Mæsia on the east to Iliria in the west. The country is now called Sclavonia.