| Plantago coronopus | GB, VC1 West Cornwall, Lizard | Cecil Ivry Sandwith Noel Yvri Sandwith | | 8/6/1937 | K |
| Mentha longifolia var. mollissima | GB, VC1 West Cornwall, Scilly Isles,Saint Marys | Cecil Ivry Sandwith | Harold Stuart Thompson | 9/1913 | BIRM |
| Veronica hederifolia | GB, VC2 East Cornwall, Cornwall,Truro,Tresillian | Cecil Ivry Sandwith | | 27/4/1935 | K |
| Galeopsis tetrahit | GB, VC2 East Cornwall, Ruan High Lanes | Cecil Ivry Sandwith Noel Yvri Sandwith | | 14/8/1934 | K |
| Mentha spicata | GB, VC2 East Cornwall, Veryan | Cecil Ivry Sandwith Noel Yvri Sandwith | | 14/8/1934 | K |
| Carex diandra | GB, VC6 North Somerset, Ashcott | Cecil Ivry Sandwith | Charles Baylis Green | 1/6/1914 | SLBI |
| Wolffia arrhiza | GB, VC6 North Somerset, Ashcott, Peat Moor | Cecil Ivry Sandwith | | 19/6/1915 | SLBI |
| Carex hirta | GB, VC6 North Somerset, Berrow | Cecil Ivry Sandwith Noel Yvri Sandwith | Royal Botanic Gardens, Kew | 8/7/1951 | BM |
| Scirpus caespitosus | GB, VC6 North Somerset, Black Down | Cecil Ivry Sandwith | Cedric Bucknall Harold Stuart Thompson | 2/6/1915 | BIRM |
| Gnaphalium uliginosum | GB, VC6 North Somerset, Blagdon | Cecil Ivry Sandwith Harold Stuart Thompson | Harold Stuart Thompson | 13/10/1933 | BIRM |
| Stachys palustris | GB, VC6 North Somerset, Catcott | Cecil Ivry Sandwith Noel Yvri Sandwith | | 21/7/1958 | K |
| Mentha piperita var. piperita | GB, VC6 North Somerset, Charterhouse on Mendip | Cecil Ivry Sandwith Noel Yvri Sandwith | | 8/8/1959 | K |
| Mentha piperita var. piperita | GB, VC6 North Somerset, Charterhouse on Mendip | Cecil Ivry Sandwith Noel Yvri Sandwith | | 8/8/1959 | K |
| Euonymus europaeus | GB, VC6 North Somerset, Clay Bottom | Cecil Ivry Sandwith Harold Stuart Thompson | Job Edward Lousley | 7/11/1933 | SLBI |
| Ligustrum vulgare | GB, VC6 North Somerset, Cleeve Toot | Cecil Ivry Sandwith Noel Yvri Sandwith | | 29/12/1945 | K |
| Festuca arundinacea | GB, VC6 North Somerset, Clifton Bridge | Cecil Ivry Sandwith Noel Yvri Sandwith | | 9/5/1955 | K |
| Mentha arvensis | GB, VC6 North Somerset, Cranmore | Cecil Ivry Sandwith Noel Yvri Sandwith | | 30/7/1941 | K |
| Veronica catenata | GB, VC6 North Somerset, Gurney Slade | Cecil Ivry Sandwith Noel Yvri Sandwith | | 6/8/1959 | K |
| Callitriche truncata | GB, VC6 North Somerset, Kingston Seymour | Cecil Ivry Sandwith Noel Yvri Sandwith | | 24/9/1951 27/9/1951 | K |
| Ajuga reptans | GB, VC6 North Somerset, Leigh Woods | Cecil Ivry Sandwith Noel Yvri Sandwith | | 15/5/1927 | K |
| Sorbus bristoliensis | GB, VC6 North Somerset, Leigh Woods | Cecil Ivry Sandwith Harold Stuart Thompson | Harold Stuart Thompson | 6/8/1933 | BIRM |
| Sorbus intermedia | GB, VC6 North Somerset, Leigh Woods | Williams Alfred James Wilmott Cecil Ivry Sandwith Harold Stuart Thompson | Harold Stuart Thompson | 16/6/1935 to 5/10/1935 | BIRM |
| Viola | GB, VC6 North Somerset, Leigh Woods | Cecil Ivry Sandwith Harold Stuart Thompson | Harold Stuart Thompson | 12/5/1915 | BIRM |
| Veronica scutellata | GB, VC6 North Somerset, Nailsea | Cecil Ivry Sandwith Noel Yvri Sandwith | | 1/7/1947 | K |
| Veronica catenata | GB, VC6 North Somerset, Portbury | Cecil Ivry Sandwith Noel Yvri Sandwith | | 19/6/1929 | K |
| Mentha x piperita var. vulgaris | GB, VC6 North Somerset, Priddy | Cecil Ivry Sandwith Noel Yvri Sandwith | | 8/9/1923 | K |
| Juncus tenuis | GB, VC6 North Somerset, River Avon | Cecil Ivry Sandwith Harold Stuart Thompson | Harold Stuart Thompson | 12/5/1915 1/9/1917 2/1/1918 | BIRM |
| Mentha gentilis var. gracilis | GB, VC6 North Somerset, Sharpham Moor | Cecil Ivry Sandwith Noel Yvri Sandwith | | 13/9/1933 | K |
| Plantago coronopus | GB, VC6 North Somerset, Steep Holm | Cecil Ivry Sandwith John Patrick Micklethwait Brenan | | 30/5/1937 | K |
| Clinopodium ascendens | GB, VC6 North Somerset, Tickenham | Cecil Ivry Sandwith Noel Yvri Sandwith | | 11/8/1956 | K |
| Cuscuta epithymum | GB, VC6 North Somerset, Tickenham | Cecil Ivry Sandwith Noel Yvri Sandwith | | 24/9/1944 | K |
| Plantago lanceolata var. anthoviridis | GB, VC6 North Somerset, Tickenham | Cecil Ivry Sandwith Noel Yvri Sandwith | | 15/5/1951 | K |
| Rumex obtusifolius | GB, VC6 North Somerset, Tickenham | Cecil Ivry Sandwith | Job Edward Lousley | 2/10/1940 | SLBI |
| Veronica hederifolia subsp. sublobata | GB, VC6 North Somerset, Tickenham | Cecil Ivry Sandwith | | 5/5/1941 | K |
| Mentha x verticillata var. paludosa | GB, VC6 North Somerset, Wedmore | Cecil Ivry Sandwith | | 9/8/1928 | K |
| Eriophorum vaginatum | GB, VC6 North Somerset, Westhay Moor | Cecil Ivry Sandwith Harold Stuart Thompson | Harold Stuart Thompson | 10/7/1935 | BIRM |
| Rumex palustris | GB, VC6 North Somerset, Westhay Moor | Cecil Ivry Sandwith Harold Stuart Thompson | Harold Stuart Thompson | 10/7/1935 | BIRM |
| Callitriche obtusangula | GB, VC6 North Somerset, Weston in Gordano | Cecil Ivry Sandwith Noel Yvri Sandwith | | 3/6/1956 | K |
| Veronica beccabunga | GB, VC6 North Somerset, Weston in Gordano | Cecil Ivry Sandwith Noel Yvri Sandwith | | 9/6/1930 | K |
| Ajuga reptans | GB, VC6 North Somerset, Tickenham GB, VC6 North Somerset, Wraxall | Cecil Ivry Sandwith | | 26/5/1930 | K |