A compilation of morainic features, eskers, glacial striations, and radiocarbon dates relating to final deglaciation is presented for the Appalachian Mountains and St. Lawrence Lowlands areas of southern Quebec. The data have been obtained largely by Geological Survey of Canada mapping since 1950. An active ice-front retreated northward and northwestward down the topographic gradient in the Appalachian region and deposited a series of discontinuous moraines, largely composed of ice-contact stratified drift, in the glacial lakes at the ice-front. The Highland Front moraine system was deposited along the northwest flank of the Appalachians about 12, 500 B. P. Deglaciation may have begun near the Quebec-Maine border as early as 14,900 B. P. and, except for an area near Thetford Mines where active out­flow persisted for a time, the Appalachian region was ice free by 12,000 B. P. when the Champlain Sea flooded the St. Lawrence Lowlands. Retreat north­westward across the lowlands continued, and the St. Narcisse Moraine was deposited between 11,100 and 11, 600 B. P. as the ice front stood in the sea. The Champlain Sea episode ended gradually in the lowlands about 9, 500 B. P. by which time the level of the freshening water body had fallen below 300 feet a. s.1.