Dundee, Edinburgh and Glasgow are regarded as belonging, respectively to the county of Aberdeen, the county of Angus, the county of Midlothian and the county of Lanark. 1955 boundaries were used also for the general election of 1959. There were changes to the boundaries of nine Scottish constituencies for the 1964 general election but there was no change to county groupings, to the total numbers of constituencies and MPs, or to constituency names. 1964 boundaries were used also for the 1966 and 1970 general elections. 1974 to 1983 The results of the Second Periodical Review, concluded in 1969, and of a subsequent interim review, concluded in 1972, became effective for the February 1974 general election. The reviews defined 29 burgh constituencies and 42 county constituencies, with each electing one MP. Therefore, Scotland had 71 parliamentary seats. Each constituency was entirely within a county or a grouping of two or three counties. February 1974 boundaries were used also in the October 1974 and 1979 general elections. 1983 to 1997 The results of the Third Periodical Review became effective for the 1983 general election. The review defined 30 burgh constituencies and 42 county constituencies, with each electing one MP. Therefore, Scotland had 72 parliamentary seats. In 1975, Scottish counties and burghs had been abolished for local government purposes, under the Local Government (Scotland) Act 1973, and the Third Periodical Review took account of new local government boundaries, which defined two-tier regions and districts and unitary islands council areas. No new constituency straddled a regional boundary, and no islands council area was divided between two constituencies. The boundary commission was required to designate each new constituency as either burgh or county but had no predetermined basis on which to do so. The commission took the view that each constituency with more than a token rural electorate would be a county constituency, and others, predominantly urban, would be burgh constituencies. 1983 boundaries were used also in the 1987 and 1992 general elections. 1997 to 2005 The results of the Fourth Periodical Review of the Boundary Commission for Scotland became effective, as a result of Order in Council SI 1995 No 1037 (S.90), for the 1997 general election. The review defined 28 burgh constituencies and 44 county constituencies, with each electing one MP. Therefore, Scotland had 72 parliamentary seats. Constituencies were defined in reference to the boundaries of local government regions and districts and islands