As defined in the 1885 Act, the constituency consisted of the "Parishes of Aberdalgie, Alyth, Abernyte, Auchtergaven, Arngask, Abernethy, Blairgowrie, Bendochy, Coupar-Angus, Cargill, Caputh (except the detached portions locally situated in Forfarshire), Collace, Clunie, Dunbarney, Dunning, the detached portion of the parish of Dunkeld and Dowally which contains the town of Dunkeld, Dron, Errol, Fowlis-Easter, Forteviot, Forgandenny, Findogask, Inchture, so much of the parish of Kettins as is locally situate in Perthshire, Kinloch, Kinfauns, Kinclaven, Kinnaird, Kinnoull, Kilspindie, Lethendy, Longforgan (including so much of the parish of ‘Liff, Benvie, and Invergowrie’ as is situate in Perthshire), Meigle, Methven, Moneydie, Perth, Redgorton, Tibbermore, Rattray, Rhynd, Scone, St. Martins, and St. Madoes." [2]
By 1918, throughout most of Scotland, county boundaries had been altered, and detached parishes were generally historic. The Representation of the People Act 1918 took account of new local government boundaries and grouped the county of Perth with the county of Kinross for parliamentaty representation purposes. Therefore, for the 1918 general election, the two counties were covered by the Perth constituency, which was now a county constituency, entirely within the county of Perth, and the Kinross and West Perthshire constituency, which covered the county of Kinross and part of the county of Perth.[1]