| Poa alpina | GB, VC49 Caernarvonshire, Snowdon | E Holmes | John Stevens Henslow | 7/1832 | BIRM |
| Poa alpina | GB, VC90 Angus, Glen Isla | Robert Kaye Greville | John Stevens Henslow | 1832 | BIRM |
| Phalaris paradoxa | GB, VC9 Dorset, Isle of Purbeck | I Austen | John Stevens Henslow | | BIRM |
+ | Peucedanum palustre | GB, VC29 Cambridgeshire, Burwell Fen | John Stevens Henslow | John Hutton Balfour | 19/8/1831 | PTH |
+ | Otanthus maritimus | GB, VC25 East Suffolk, Dunwich | John Stevens Henslow | Warrington Museum William Wilson | 7/8/1829 | MANCH |
+ | Onobrychis viciifolia | GB, VC29 Cambridgeshire, Newmarket, Devils Ditch | John Stevens Henslow | | 20/6/1826 | MANCH |
+ | Nepeta cataria | GB, VC16 West Kent, Wilmington | John Stevens Henslow | Charles Bailey John Stevens Henslow | 1838 | MANCH |
+ | Monotropa hypopitys | GB, VC22 Berkshire, Cholsey | John Stevens Henslow | Bowman | 7/1835 | MANCH |
| Molinia caerulea | GB, VC90 Angus, Clova Mountains | Graham Robert Kaye Greville | John Stevens Henslow | 1832 | BIRM |
+ | Moenchia erecta | GB, VC14 East Sussex, Hastings | John Stevens Henslow | John Hutton Balfour | 1836 | PTH |
+ | Minuartia hybrida | GB, VC29 Cambridgeshire, Gog Magog Hills | John Stevens Henslow | Warrington Museum William Wilson | 2/6/1825 | MANCH |
+ | Minuartia hybrida | GB, VC29 Cambridgeshire, Gog Magog Hills | John Stevens Henslow | John Hutton Balfour | 24/5/1834 | PTH |
| Mentha arvensis x spicata = M. x gracilis | GB, VC39 Staffordshire, Tutbury | Charles Cardale Babington | John Stevens Henslow | 10/9/1832 | CGE |
| Mentha arvensis x spicata = M. x gracilis | GB, VC40 Shropshire | Bell Edward Williams | John Stevens Henslow | | CGE |
| Mentha arvensis x spicata = M. x gracilis | GB, VC59 South Lancashire, Warrington | William Wilson | John Stevens Henslow | 8/1824 | CGE |
| Mentha arvensis x spicata = M. x gracilis | GB, VC83 Midlothian, Roslin | John Hutton Balfour | John Stevens Henslow | 9/1835 | CGE |
| Mentha arvensis x aquatica x spicata = M. x smithiana | GB, VC58 Cheshire, Newchurch | William Wilson | John Stevens Henslow | 11/1826 | CGE |
| Mentha arvensis x aquatica x spicata = M. x smithiana | GB, VC64 Mid-west Yorkshire, Ripon | Samuel Hailstone | John Stevens Henslow | | CGE |
| Mentha arvensis x aquatica x spicata = M. x smithiana | GB, VC64 Mid-west Yorkshire, Settle | John Howson | John Stevens Henslow | 8/1833 | CGE |
| Mentha arvensis x aquatica x spicata = M. x smithiana | GB, VC64 Mid-west Yorkshire, Settle | John Howson | John Stevens Henslow | 8/1833 | CGE |
| Mentha arvensis x aquatica = M. x verticillata | GB, VC6 North Somerset, Bath | Charles Cardale Babington | John Stevens Henslow | 9/1833 | CGE |
| Mentha arvensis x aquatica = M. x verticillata | GB, VC29 Cambridgeshire, Madingley | John Stevens Henslow | John Stevens Henslow | 31/7/1828 | CGE |
| Mentha arvensis x aquatica = M. x verticillata | GB, VC59 South Lancashire, Warrington | William Wilson | John Stevens Henslow | 8/1824 | CGE |
| Mentha arvensis | GB, VC29 Cambridgeshire, Cherry Hinton | John Stevens Henslow | William Jackson Hooker | 27/7/1824 | K |
| Mentha aquatica x spicata = M. x piperita var. officinalis | GB, VC19 North Essex, Great Leighs | William Peete | John Stevens Henslow | 4/9/1828 | CGE |
| Mentha aquatica x spicata = M. x piperita | GB, VC59 South Lancashire, Warrington | William Wilson | John Stevens Henslow | 9/1825 to 9/1826 | CGE |
| Mentha aquatica x spicata = M. x piperita | GB, VC65 North-west Yorkshire, Richmond | James Ward | John Stevens Henslow | 9/9/1831 | CGE |
| Mentha aquatica x spicata = M. x piperita var. crispa | GB, VC68 North Northumberland, Langleeford | Charles Cardale Babington | George Johnston John Stevens Henslow | 10/9/1834 | CGE |
| Melica uniflora | GB, VC22 Berkshire, Cholsey | John Stevens Henslow | Mantua And Montferrat | 2/7/1835 | BON |
+ | Matthiola sinuata | GB, VC48 Merionethshire, Barmouth | John Stevens Henslow | Charles Bailey John Wilson Rimington Spencer Henry Bickham | 8/1831 | MANCH |
+ | Lythrum hyssopifolia | GB, VC29 Cambridgeshire, Cambridge | John Stevens Henslow | Warrington Museum William Wilson | 6/8/1828 | MANCH |
| Liparis loeselii | GB, VC29 Cambridgeshire, Burwell Fen | John Eddowes Bowman John Stevens Henslow | | 7/1836 1839 | SLBI |
+ | Liparis loeselii | GB, VC29 Cambridgeshire, Burwell,Burwell Fen | John Stevens Henslow | Samuel Octavus Gray | 7/1835 | MANCH |
| Lemna gibba | GB, VC22 Berkshire, Cholsey | John Stevens Henslow | Mantua And Montferrat | 7/1835 | BON |
+ | Lathyrus aphaca | GB, VC22 Berkshire, Henley on Thames | John Stevens Henslow | Samuel Octavus Gray | | MANCH |
+ | Lathyrus aphaca | GB, VC29 Cambridgeshire, Cambridge,Hinton | John Stevens Henslow | Warrington Museum William Wilson | 1/4/1830 | MANCH |
+ | Lathyrus aphaca | GB, VC29 Cambridgeshire, Teversham | John Stevens Henslow | Warrington Museum William Wilson | 20/7/1823 | MANCH |
| Isolepis cernua | GB, VC74 Wigtownshire, East Tarbet | Balfour | John Stevens Henslow | | BIRM |
| Isolepis cernua | IE, VCH16,VCH27, Leenane | Charles Cardale Babington | John Stevens Henslow | 25/8/1835 | BIRM |
| Inula helenium | GB, VC40 Shropshire, Frodesley | John Stevens Henslow | Charles Bailey John Wilson Rimington | 5/9/1830 | MANCH |