| Carex otrubae x remota = C. x pseudoaxillaris | GB, VC19 North Essex, Inworth | Ezekiel George Varenne | William Williamson Newbould | 7/1847 | BM |
| Rumex crispus x obtusifolius = R. x pratensis | GB, VC20 Hertfordshire, Broxbourne | William Williamson Newbould | Charles Bailey William Williamson Newbould | 19/7/1848 | MANCH |
| Carex otrubae x remota = C. x pseudoaxillaris | GB, VC20 Hertfordshire, Buntingford | William Williamson Newbould | | 21/7/1848 | BM |
| Carex remota | GB, VC20 Hertfordshire, Buntingford | William Williamson Newbould | William Williamson Newbould | 3/8/1847 | BM |
| Carex remota x vulpina = C. axilaris | GB, VC20 Hertfordshire, Buntingford | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 21/7/1848 | SLBI |
| Epipactis phyllanthes | GB, VC20 Hertfordshire, Buntingford, Throcking | William Williamson Newbould | Frederick Townsend | 8/4/1847 | SLBI |
| Carex otrubae x remota = C. x pseudoaxillaris | GB, VC20 Hertfordshire, Layston | William Williamson Newbould | | | BM |
| Bromus commutatus | GB, VC21 Middlesex, Acton | William Williamson Newbould | Augustin Ley | 6/1867 | BIRM |
+ | Bromus secalinus | GB, VC21 Middlesex, Brentford | William Williamson Newbould | Charles Bailey | 6/1867 | MANCH |
| Carex paniculata | GB, VC21 Middlesex, Willesden | William Williamson Newbould | John Thomas Irvine Boswell-Syme | 7/1867 | BM |
| Carex riparia | GB, VC21 Middlesex, Willesden | William Williamson Newbould | John Thomas Irvine Boswell-Syme | 7/1867 | BM |
| Rumex obtusifolius var. sylvestris | GB, VC17,VC21, Putney | William Williamson Newbould | Frederick Townsend | | SLBI |
| Carex paniculata | GB, VC25 East Suffolk, Belton Fen | William Williamson Newbould | | 8/6/1847 | BM |
| Urtica pilulifera | GB, VC25 East Suffolk, Lowestoft | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 1854 | SLBI |
| Carex divisa | GB, VC25 East Suffolk, Walton | William Williamson Newbould | William Williamson Newbould | 8/1864 | BM |
| Crepis foetida | GB, VC26 West Suffolk, Brandon | William Williamson Newbould | Frederick Townsend | 4/7/1848 | SLBI |
| Medicago sativa subsp. falcata | GB, VC26 West Suffolk, Thetford | William Williamson Newbould | Frederick Townsend | 15/8/1851 | SLBI |
| Carex divisa | GB, VC27 East Norfolk, Yarmouth | William Williamson Newbould | | 7/7/1847 | BM |
| Ranunculus baudotii | GB, VC28 West Norfolk, Burnham Norton | William Williamson Newbould | Allan Octavian Hume Charles Cardale Babington Frederick Townsend | 24/5/1852 | SLBI |
| Scleranthus annuus | GB, VC28 West Norfolk, Thetford | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 4/7/1848 | SLBI |
| Mentha aquatica x spicata = M. x piperita | GB, VC29 Cambridgeshire, Barrington | William Williamson Newbould | | 9/9/1856 | CGE |
| Allium oleraceum | GB, VC29 Cambridgeshire, Barton | William Williamson Newbould | | 1850 | SLBI |
| Allium oleraceum | GB, VC29 Cambridgeshire, Barton | William Williamson Newbould | Allan Octavian Hume | 1850 | SLBI |
| Viola persicifolia | GB, VC29 Cambridgeshire, Bottisham | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 8/1852 | SLBI |
| Potamogeton coloratus | GB, VC29 Cambridgeshire, Bottisham Fen | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 23/7/1847 | SLBI |
| Potamogeton polygonifolius | GB, VC29 Cambridgeshire, Bottisham Fen | William Williamson Newbould | William Williamson Newbould | 23/7/1847 | SLBI |
| Viola | GB, VC29 Cambridgeshire, Cambridge | Charles Cardale Babington William Henry Purchas William Williamson Newbould | Augustin Ley | 1857 | BIRM |
+ | Groenlandia densa | GB, VC29 Cambridgeshire, Cambridge (N of),Swaffham | George Bitton Jermyn | Charles Bailey William Williamson Newbould | 7/1836 | MANCH |
| Lathyrus aphaca | GB, VC29 Cambridgeshire, Cherry Hinton | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | | SLBI |
| Silene noctiflora | GB, VC29 Cambridgeshire, Chippenham | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 29/7/1852 | SLBI |
| Ranunculus parviflorus | GB, VC29 Cambridgeshire, Comberton | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | | SLBI |
| Stachys sylvatica x palustris = S. x ambigua | GB, VC29 Cambridgeshire, Coton | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 26/7/1844 | SLBI |
| Galium album | GB, VC29 Cambridgeshire, Eversden | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 14/6/1848 | SLBI |
| Cerastium fontanum subsp. vulgare | GB, VC29 Cambridgeshire, Gamlingay | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 5/4/1849 | SLBI |
+ | Genista anglica | GB, VC29 Cambridgeshire, Gamlingay | | Charles Bailey John Barrow William Williamson Newbould | 20/5/1847 | MANCH |
+ | Teesdalia nudicaulis | GB, VC29 Cambridgeshire, Gamlingay | William Williamson Newbould | Charles Bailey John Ray Hardy | 3/4/1842 | MANCH |
| Thalictrum minus | GB, VC29 Cambridgeshire, Gog Magog Hills | William Williamson Newbould | | 21/9/1851 | SLBI |
+ | Ranunculus | GB, VC29 Cambridgeshire, Haddenham | William Williamson Newbould | Charles Bailey John Ray Hardy | 6/9/1846 | MANCH |
| Thymus chamaedrys | GB, VC29 Cambridgeshire, Harlton | William Williamson Newbould | Charles Cardale Babington George Stephen West | 1/7/1853 | BIRM |
| Caucalis platycarpos | GB, VC29 Cambridgeshire, Harston | William Williamson Newbould | Allan Octavian Hume Frederick Townsend | 17/7/1848 | SLBI |