This constituency comprised the northern part of County Leitrim.
1885–1918: The baronies of Dromahair and Rosclogher, and that part of the barony of Leitrim contained within the parish of Kiltubbrid and the townlands of Acres, Aghagrania, Aghnagollop, Ardcolum, Barnameenagh, Barnameenagh West, Blackrock, Carrickbaun, Carricknabrack, Corlough, Corloughlin, Cormeeltan, Cormongan, Cornamuddagh, Cornashamsoge, Corrachuill, Corryard, Creenagh, Crey, Derrintober, Derrintonagh, Derryhallagh, Derrynaseer, Derryteigeroe, Dorrusawillin, Dristernaun, Drumcoora, Drumcroman, Drumderg, Drumhalwy, Drumduff, Drumshanbo, Greaghfarnagh, Greaghnaguillaun, Largan, Largan Mountain, Lavaur, Mahanagh, Moneynure, Murhaun, Roscunnish, Shancurry and Sheskinacurry in the parish of Kiltoghert.