| Centaurium erythraea | GB, VC3 South Devon, Teignmouth | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 7/1876 | BIRM |
| Cerastium arvense | GB, VC38 Warwickshire, Sutton Park | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 24/5/1852 | BIRM |
| Cerastium glomeratum | GB, VC3 South Devon, Teignmouth | Charles James Rufus Jordan | Robert Coane Roberts Jordan | 30/3/1846 | BIRM |
| Cerastium glomeratum | GB, VC38 Warwickshire, Birmingham | Robert Coane Roberts Jordan | | 6/1852 | BIRM |
| Cerastium glomeratum | GB, VC38 Warwickshire, Birmingham | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 7/1880 | BIRM |
| Cerastium glomeratum | GB, VC38 Warwickshire, Sutton Coldfield | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 21/5/1853 | BIRM |
| Ceratocapnos claviculata | GB, VC3 South Devon, Teignmouth | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 7/1876 | BIRM |
| Ceratocapnos claviculata | GB, VC37 Worcestershire | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 1878 | BIRM |
| Ceratocapnos claviculata | GB, VC40 Shropshire, Wrekin | Robert Coane Roberts Jordan | | 4/6/1853 | BIRM |
| Ceratocapnos claviculata | GB, VC40 Shropshire, Wrekin | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 4/6/1853 | BIRM |
| Chaenorhinum minus | GB, VC3 South Devon, Saltram | Isaiah Waterloo Nicholson Keys | Robert Coane Roberts Jordan | 23/7/1845 | BIRM |
| Chrysanthemum leucanthemum | GB, VC39 Staffordshire, Harborne | Emily Francis Jordan Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 6/1875 | BIRM |
| Circaea lutetiana | GB, VC3 South Devon, Lympstone | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 15/7/1846 | BIRM |
| Cirsium arvense | GB, VC38 Warwickshire, Birmingham | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 7/1875 | BIRM |
| Cirsium dissectum | GB, VC9 Dorset, Glanvilles Wootton | William Risdon Hall Jordan | Robert Coane Roberts Jordan | 1848 | BIRM |
| Cirsium oleraceum | DE, Hessen, Frankfurt | Robert Coane Roberts Jordan | | 23/8/1853 | BIRM |
| Clinopodium ascendens | GB, VC3 South Devon, Teignmouth | Charles James Rufus Jordan | Robert Coane Roberts Jordan | 8/1850 | BIRM |
| Clinopodium vulgare | GB, VC3 South Devon, Teignmouth | Charles James Rufus Jordan | Robert Coane Roberts Jordan | 8/1830 | BIRM |
| Cochlearia anglica | GB, VC3 South Devon, Teignmouth | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | | BIRM |
| Cochlearia danica | GB, VC3 South Devon, Teignmouth | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 7/4/1849 | BIRM |
| Colchicum autumnale | GB, VC65 North-west Yorkshire, Redmire | Langley Kitching | Robert Coane Roberts Jordan | 11/9/1880 | BIRM |
| Conium maculatum | GB, VC3 South Devon, Teignmouth | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 7/1876 | BIRM |
| Conopodium majus | GB, VC38 Warwickshire, Birmingham | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 6/1875 | BIRM |
| Consolida ajacis | FR, Martigny | Robert Coane Roberts Jordan | | 6/1880 | BIRM |
| Conyza | DE, Rheinland-Pfalz, Koblenz | Robert Coane Roberts Jordan | | 21/8/1853 | BIRM |
| Conyza canadensis | DE, Nordrhein-Westfalen, Köln | Robert Coane Roberts Jordan | | 18/8/1853 | BIRM |
| Coronopus didymus | GB, VC3 South Devon, Starcross | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 11/7/1846 | BIRM |
| Coronopus didymus | GB, VC3 South Devon, Teignmouth | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 7/1876 | BIRM |
| Coronopus squamatus | GB, VC3 South Devon, Lympstone | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 2/8/1846 | BIRM |
| Crataegus laevigata | GB, VC37 Worcestershire, Lickey | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 6/1875 | BIRM |
| Crocus vernus | GB, VC56 Nottinghamshire, Nottingham | | Robert Coane Roberts Jordan | | BIRM |
| Cruciata laevipes | GB, VC37 Worcestershire, Lickey | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 8/1875 | BIRM |
| Cuscuta epithymum | GB, VC3 South Devon, Haldon | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 6/8/1880 | BIRM |
| Cuscuta epithymum | GB, VC16 West Kent, Cobham | Charles James Rufus Jordan | Robert Coane Roberts Jordan | 8/1850 | BIRM |
| Cystopteris fragilis | GB, VC57 Derbyshire, Matlock | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 20/6/1853 | BIRM |
| Cystopteris fragilis | GB, VC77 Lanarkshire, Stonebyres | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 24/8/1852 | BIRM |
| Cystopteris fragilis | NO, More og Romsdal, Ormeim | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 7/1888 | BIRM |
| Dactylorhiza praetermissa | GB, VC3 South Devon, Broadmeadow, Teignmouth | Robert Coane Roberts Jordan | George Stephen West Robert Coane Roberts Jordan | 1844 | BIRM |
| Daphne laureola | GB, VC36 Herefordshire, Ledbury | William Groves Perry | George Stephen West Robert Coane Roberts Jordan | 4/1852 | BIRM |
| Datura stramonium | GB, VC3 South Devon, Exmouth | Robert Coane Roberts Jordan | Robert Coane Roberts Jordan | 1846 | BIRM |