| Hordelymus europaeus | GB, VC20 Hertfordshire, Aldbury, The Hangings | William Higgins Coleman | | 24/7/1840 | BON |
| Carex otrubae x remota = C. x pseudoaxillaris | GB, VC20 Hertfordshire, Astonbury Wood | William Higgins Coleman | Philip Brookes Mason | | BON |
| Iberis amara | GB, VC20 Hertfordshire, Baldock | William Higgins Coleman | Augustin Ley | 13/8/1841 | BIRM |
| Carex remota x vulpina = C. axilaris | GB, VC20 Hertfordshire, Ball's Wood | William Higgins Coleman | Frederick Townsend | 1843 | SLBI |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Balls Wood | William Higgins Coleman | Charles Cardale Babington George Stephen West William West | 3/7/1844 | BIRM |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Balls Wood | William Higgins Coleman | Charles Cardale Babington | 3/7/1844 | BM |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Balls Wood | William Higgins Coleman | Philip Brookes Mason | | BON |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Balls Wood | William Higgins Coleman | Edward Forster | 15/6/1842 | BM |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Balls Wood | William Higgins Coleman | | 3/7/1844 | BON |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Balls Wood | William Higgins Coleman | Mary Ann Brooks | 1845 | BIRM |
| Carex sylvatica | GB, VC20 Hertfordshire, Balls Wood | William Higgins Coleman | | | BON |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Balls Wood, Hertford | William Higgins Coleman | George Stephen West | 3/7/1844 | BIRM |
| Schoenus nigricans | GB, VC20 Hertfordshire, Barkway | William Higgins Coleman | | 3/6/1840 | BON |
| Avena strigosa | GB, VC20 Hertfordshire, Bayford | William Higgins Coleman | Philip Brookes Mason | 12/7/1844 | BON |
| Ophrys apifera | GB, VC20 Hertfordshire, Bayford | William Higgins Coleman | | 3/7/1840 | BON |
| Carex vesicaria | GB, VC20 Hertfordshire, Bayford Wood | William Higgins Coleman | | 1839 | BON |
| Mentha aquatica x spicata = M. x piperita | GB, VC20 Hertfordshire, Bengeo | William Higgins Coleman | Druce Herbarium, Oxford | 30/9/1843 | OXF |
| Eleocharis multicaulis | GB, VC20 Hertfordshire, Bishops Hatfield | William Higgins Coleman | | 24/6/1843 | BON |
| Eleocharis quinqueflora | GB, VC20 Hertfordshire, Bishops Hatfield | William Higgins Coleman | | 24/6/1843 | BON |
| Polystichum aculeatum | GB, VC20 Hertfordshire, Bramfield | William Higgins Coleman | | 7/8/1840 | BON |
| Carex pendula | GB, VC20 Hertfordshire, Brickendon | William Higgins Coleman | | 12/5/1841 | BON |
| Dactylorhiza incarnata | GB, VC20 Hertfordshire, Brickendon | William Higgins Coleman | | 13/6/1846 | BON |
| Carex diandra | GB, VC20 Hertfordshire, Broxbourne | William Higgins Coleman | Philip Brookes Mason | | BON |
| Scirpus sylvaticus | GB, VC20 Hertfordshire, Broxbourne Woods | William Higgins Coleman | | 4/7/1840 | BON |
| Ononis spinosa | GB, VC20 Hertfordshire, Cheshunt | William Higgins Coleman | Philip Brookes Mason | 30/6/1844 | BON |
| Carex otrubae x remota = C. x pseudoaxillaris | GB, VC20 Hertfordshire, Colliers End | William Higgins Coleman | | 9/5/1846 | BON |
| Carex otrubae x remota = C. x pseudoaxillaris | GB, VC20 Hertfordshire, Colney Heath | William Higgins Coleman | | 27/5/1846 | BON |
| Sparganium emersum | GB, VC20 Hertfordshire, Colney Heath | William Higgins Coleman | | 17/7/1840 | BON |
| Juncus inflexus x effusus = J. x diffusus | GB, VC20 Hertfordshire, Darman's Green | William Higgins Coleman | Charles Bailey William Lowndes Notcutt | 1846 | MANCH |
| Sparganium natans | GB, VC20 Hertfordshire, Digswell | William Higgins Coleman | | 7/9/1842 | BON |
| Eleocharis acicularis | GB, VC20 Hertfordshire, Elstree Reservoir | William Higgins Coleman | | 8/8/1844 | BON |
| Iris foetidissima | GB, VC20 Hertfordshire, Foxley Wood | William Higgins Coleman | | 6/1840 | BON |
| Herminium monorchis | GB, VC20 Hertfordshire, Hatfield Park | William Higgins Coleman | Philip Brookes Mason | 17/7/1841 | BON |
| Allium vineale | GB, VC20 Hertfordshire, Hertford | William Higgins Coleman | Philip Brookes Mason | | BON |
| Avena fatua | GB, VC20 Hertfordshire, Hertford | William Higgins Coleman | Philip Brookes Mason | | BON |
| Bromus secalinus | GB, VC20 Hertfordshire, Hertford | William Higgins Coleman | Philip Brookes Mason | | BON |
| Calamagrostis epigejos | GB, VC20 Hertfordshire, Hertford | William Higgins Coleman | | 14/7/1840 | BON |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Hertford | William Higgins Coleman | Charles Cardale Babington George Stephen West William West | 7/3/1844 | BIRM |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Hertford | William Higgins Coleman | John Thomas Irvine Boswell-Syme | 15/6/1842 | BM |
| Carex paniculata x remota = C. x boenninghauseniana | GB, VC20 Hertfordshire, Hertford | William Higgins Coleman | Allan Octavian Hume Frederick Townsend | 8/1845 | SLBI |