+ | Zostera marina | GB, VC11 South Hampshire, Pennington Marshes | Norman Douglas Simpson | Botanical Society & Exchange Club of The British Isles Norman Douglas Simpson | 7/9/1937 | MANCH |
| Vicia orobus | GB, VC70 Cumberland, Langwathby | Norman Douglas Simpson | George Valentine Chapman Last | 1909 | K |
| Veronica triphyllos | GB, VC26 West Suffolk, Cavenham | Norman Douglas Simpson | Harold Stuart Thompson | 6/1910 | BIRM |
| Vaccaria hispanica | GB, VC62 North-east Yorkshire, Thirsk | Norman Douglas Simpson | Harold Stuart Thompson | 1904 | BIRM |
| Thymus praecox subsp. arcticus | IE, VCH34,VCH40, Magilligan Point | Norman Douglas Simpson | John Patrick Micklethwait Brenan | 6/8/1938 | K |
| Thymus praecox subsp. arcticus | IE, VCH40 Co. Londonderry, Magilligan point | John Patrick Micklethwait Brenan Norman Douglas Simpson | | 6/8/1938 | K |
| Saxifraga rivularis | GB, VC97 West Inverness-shire, Ben Nevis | Norman Douglas Simpson | Harold Stuart Thompson | 3/9/1913 | BIRM |
| Satureja montana | GB, VC11 South Hampshire, Beaulieu Abbey | John Patrick Micklethwait Brenan Norman Douglas Simpson Richard Charles L'Estrange Burges | John Patrick Micklethwait Brenan | 5/9/1938 | K |
| Rubus pruinosus | IE, VCH39 Co. Antrim, Drumnadarragh | John Patrick Micklethwait Brenan Norman Douglas Simpson | | 17/8/1939 | SLBI |
| Rubus pruinosus | IE, VCH39 Co. Antrim, Drumnadarragh | John Patrick Micklethwait Brenan Norman Douglas Simpson | William Charles Richard Watson | 17/8/1939 | SLBI |
| Rubus lettii | IE, VCH38 Co. Down, Banbridge | John Patrick Micklethwait Brenan Norman Douglas Simpson | Norman Douglas Simpson | 1/8/1938 | SLBI |
| Rubus lettii | IE, VCH39 Co. Antrim, Crumlin | John Patrick Micklethwait Brenan Norman Douglas Simpson | Norman Douglas Simpson | 16/8/1939 | SLBI |
| Prunella vulgaris x laciniata = P. x intermedia | GB, VC29 Cambridgeshire, Hardwicke | Norman Douglas Simpson | Harold Stuart Thompson | 18/7/1913 | BIRM |
| Potamogeton nodosus | GB, VC9 Dorset, Child Okeford | Norman Douglas Simpson | Norman Douglas Simpson | 19/10/1937 | E |
| Potamogeton nodosus | GB, VC9 Dorset, Child Okeford | Norman Douglas Simpson | Norman Douglas Simpson | 19/10/1937 | E |
| Potamogeton nodosus | GB, VC9 Dorset, Child Okeford | Norman Douglas Simpson | Norman Douglas Simpson | 19/10/1937 | E |
| Potamogeton lucens x gramineus = P. x angustifolius | GB, VC79 Selkirkshire, Cauldshields Lough | Norman Douglas Simpson | Robert MacKechnie | 11/9/1933 | E |
| Potamogeton coloratus x berchtoldii = P. x lanceolatus | GB, VC52 Anglesey, Lligwy | Norman Douglas Simpson | Harold Stuart Thompson | 9/1910 | BIRM |
+ | Potamogeton coloratus x berchtoldii = P. x lanceolatus | GB, VC52 Anglesey, Rhos Lligwy | Norman Douglas Simpson | | 9/1910 | BIRM |
| Plantago lanceolata var. anthoviridis | GB, VC9 Dorset, Cowgrove | Norman Douglas Simpson | Norman Douglas Simpson | 23/5/1923 | K |
| Mentha x piperita var. vulgaris | GB, VC3 South Devon, Ivybridge | Norman Douglas Simpson | Botanical Exchange Club of The British Isles Norman Douglas Simpson | 24/9/1937 | K |
| Mentha aquatica x spicata = M. x piperita | GB, VC3 South Devon, Ivybridge | Norman Douglas Simpson | Norman Douglas Simpson | 24/9/1937 | OXF |
| Melampyrum pratense | GB, VC65, VC66, Wynch Bridge | Norman Douglas Simpson | Harold Stuart Thompson | 1906 | BIRM |
| Ludwigia palustris | GB, VC11 South Hampshire, Lyndhurst | Norman Douglas Simpson | London Natural History Society Edmund Browne Bishop | 1/9/1921 | SLBI |
+ | Impatiens glandulifera | GB, VC17 Surrey, Bank of Thames, D.S Richmond | Norman Douglas Simpson | | 25/8/1941 | BM |
+ | Impatiens glandulifera | GB, VC35 Monmouthshire, Banks of the River Usk, an escape | Norman Douglas Simpson | | 2/10/1924 | BM |
+ | Impatiens glandulifera | GB, VC53 South Lincolnshire, Timber yard on rubble bank; outcast. Skirbeck | Arthur Hugh Garfit Alston Norman Douglas Simpson | | 5/8/1945 | BM |
+ | Impatiens glandulifera | GB, VC54 North Lincolnshire, Garden outcast, Skirbeck Road, Boston. 3 clumps in a lane | Arthur Hugh Garfit Alston Norman Douglas Simpson | | 5/8/1945 | BM |
+ | Impatiens glandulifera | GB, VC95 Moray, River Spey, shingles, Garmouth, Elgin | Norman Douglas Simpson | | 3/7/1953 | BM |
+ | Impatiens glandulifera | GB, VC95 Moray, River Spey, shingles, Garmouth, Elgin | Norman Douglas Simpson | | 3/7/1953 | BM |
| Hypochaeris glabra | GB, VC9 Dorset, Sandford | John Patrick Micklethwait Brenan Norman Douglas Simpson | John Patrick Micklethwait Brenan | 28/6/1942 | K |
| Hordeum jubatum | GB, VC61 South-east Yorkshire, York | Norman Douglas Simpson | Harold Stuart Thompson | 1906 | BIRM |
| Cerastium pumilum | GB, VC3 South Devon, Torquay | Frederick Townsend | Charles Cardale Babington Harold Stuart Thompson Norman Douglas Simpson | 22/5/1858 | BIRM |
| Carex x helvola | GB, VC9 Dorset, Edmondsham Cultivated GB, VC92 South Aberdeenshire, Lochnagar | Edward Francis Linton | Watson Botanical Exchange Club Edward Francis Linton Leslie Beeching Hall Norman Douglas Simpson | 6/1911 | BM |
| Carex x helvola | GB, VC92 South Aberdeenshire, Lochnagar | Arthur Humble Evans | Leslie Beeching Hall Norman Douglas Simpson Pfarrer G Kükenthal Arthur Bennett | 8/1925 | BM |
| Carex vulpina | GB, Sussex | | Norman Douglas Simpson Joanna Charlotte Davy | | BM |
| Carex riparia | GB, VC18 South Essex, Epping Forest | | Leslie Beeching Hall Norman Douglas Simpson | 8/6/1902 | BM |
| Carex riparia | GB, VC22 Berkshire, Clifton Hampden | Leslie Beeching Hall | Leslie Beeching Hall Norman Douglas Simpson | 22/6/1901 | BM |
| Carex riparia | GB, VC23 Oxfordshire, Kidlington | A E B | Leslie Beeching Hall Norman Douglas Simpson | 6/1904 | BM |
| Carex riparia | GB, VC23 Oxfordshire, Oxford, Port Meadow | A E B | Leslie Beeching Hall Norman Douglas Simpson | 6/1904 | BM |