| Norfolk Eastern (1885 - 1950) |
Constituency of same name also existed 1832-1868. |
| Norfolk Northern (1868 - 1950) |
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| Norfolk Southern (1868 - 1950) |
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| Norfolk South Western (1885 - 1950) |
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| Norwich (1832 - 1950) |
Writ suspended 1875-1880. |
| Nottingham West (1885 - 1950) |
Constituency of same name also existed 1955-1983 |
| Oldham (1832 - 1950) |
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| Oxford University (1832 - 1950) |
Non-geographic constituency. |
| Peebles and Southern (1918 - 1950) |
Full name (in Craig 3) Midlothian and Peeblesshire, Peebles and Southern |
| Penrith and Cockermouth (1918 - 1950) |
Full name (in Craig 3) Cumberland, Penrith and Cockermouth |
| Penryn and Falmouth (1832 - 1950) |
Full name (in Craig 3) Cornwall, Penryn and Falmouth |
| Perth (1832 - 1950) |
Full name (in Craig 3) Perthshire and Kinross-shire, Perth. Constituency of same name reformed 1997. |
| Plymouth, Drake (1918 - 1950) |
Seat of same name existed 1974¹-1997. |
| Poplar Bow and Bromley (1918 - 1950) |
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| Poplar South Poplar (1918 - 1950) |
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| Portsmouth Central (1918 - 1950) |
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| Portsmouth North (1918 - 1950) |
Constituency of same name reformed 1974¹. |
| Preston (1832 - 1950) |
Constituency of same name reformed 1983. |
| Pudsey and Otley (1918 - 1950) |
Full name (in Craig 3) Yorkshire (West Riding), Pudsey and Otley |
| Queen's University of Belfast (1918 - 1950) |
Non-geographic constituency. |
| Reading (1832 - 1950) |
Constituency of same name also existed 1955-1974¹. |
| Renfrewshire Eastern (1885 - 1950) |
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| Renfrewshire Western (1885 - 1950) |
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| Rochester Chatham (1918 - 1950) |
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| Rochester Gillingham (1918 - 1950) |
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