| Salix pentandra x fragilis = S. x meyeriana | GB, VC29 Cambridgeshire, Ely | William Marshall | Charles Cardale Babington | 1864 | CGE |
| Salix pentandra x fragilis = S. x meyeriana | GB, VC40 Shropshire, Hanwood | William Allport Leighton | Charles Cardale Babington | 27/6/1836 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC19 North Essex, Audley End | John Ewbank Leefe | Charles Cardale Babington | 19/3/1842 to 19/7/1842 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC40 Shropshire, Eyton | T C Eyton | Charles Cardale Babington | | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC40 Shropshire, Eyton | J C Eyton | Charles Cardale Babington | | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC40 Shropshire, Eyton upon the Weald Moore | Thomas Campbell Eyton | Charles Cardale Babington | | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC62 North-east Yorkshire, Thirsk | John Gilbert Baker | Charles Cardale Babington George Stephen West William West | 5/8/1852 | BIRM |
| Salix viminalis x caprea = S. x smithiana | GB, VC65 North-west Yorkshire, Richmond | James Ward | Charles Cardale Babington | 8/4/1841 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC65 North-west Yorkshire, Richmond | James Ward | Charles Cardale Babington John Ewbank Leefe | 7/4/1842 27/6/1842 9/7/1842 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC65 North-west Yorkshire, Richmond | James Ward | Charles Cardale Babington John Ewbank Leefe | 11/5/1842 6/8/1842 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC65 North-west Yorkshire, Richmond | James Ward | Charles Cardale Babington John Ewbank Leefe | 25/3/1842 21/6/1842 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC65 North-west Yorkshire, Richmond | James Ward | Charles Cardale Babington John Ewbank Leefe | 9/4/1842 23/7/1842 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC80 Roxburghshire, Blacklaw | Andrew Brotherston | Charles Cardale Babington | 5/1877 9/1877 | CGE |
| Salix viminalis x caprea = S. x smithiana | GB, VC80 Roxburghshire, Kelso | Andrew Brotherston | Charles Cardale Babington | 4/1875 8/1875 | CGE |
| Sanicula europaea | GB, VC85 Fifeshire, Balmerino | William Gardiner | Charles Cardale Babington William Hillhouse | | BIRM |
| Saxifraga hirsuta | GB, VC64 Mid-west Yorkshire, Chapel-le-Dale | F P Thompson Rachel Ford Thompson | Botanical Exchange Club of The British Isles Charles Cardale Babington Edward Francis Linton F P Thompson Rachel Ford Thompson William Hunt Painter | 5/7/1890 | ABS |
+ | Saxifraga tridactylites | GB, VC6 North Somerset, Batheaston | Charles Cardale Babington | John Hutton Balfour | 4/1837 | PTH |
+ | Saxifraga tridactylites | GB, VC28 West Norfolk, Walsingham | Charles Cardale Babington | John Hutton Balfour | 4/1836 | PTH |
| Scheuchzeria palustris | GB, VC40 Shropshire, Bomere Pool | Charles Cardale Babington | Allan Octavian Hume Charles Cardale Babington | 10/8/1847 | SLBI |
| Scheuchzeria palustris | GB, VC40 Shropshire, Bomere Pool | Charles Cardale Babington | Allan Octavian Hume Charles Cardale Babington | 4/8/1832 | SLBI |
| Schoenus nigricans | GB, VC29 Cambridgeshire, Thriplow | Charles Cardale Babington | Charles Cardale Babington George Stephen West William West | 28/6/1847 | BIRM |
| Scleranthus perennis | GB, VC26 West Suffolk, Icklingham | Charles Cardale Babington | William West | 25/6/1863 | BIRM |
+ | Scleranthus perennis subsp. prostratus | GB, VC26 West Suffolk, Mildenhall | Charles Cardale Babington | John Ray Hardy | 1837 | MANCH |
| Scrophularia nodosa | IE, VCH2 North Kerry, Tralee | Charles Cardale Babington | | 7/1841 | E |
| Scutellaria galericulata | GB, VC29 Cambridgeshire, Ely | Charles Cardale Babington | Shrewsbury Public Library | 5/7/1853 | K |
+ | Seseli libanotis | GB, VC29 Cambridgeshire, Cambridge | Charles Cardale Babington | John Hutton Balfour | 7/1840 | PTH |
| Setaria viridis | GB, VC17 Surrey, Weybridge | W McIvor | Charles Cardale Babington William West George Stephen West | 8/1847 | BIRM |
| Sibbaldia procumbens | GB, VC90 Angus, Clova | Charles Cardale Babington | William Hillhouse | | BIRM |
+ | Silaum silaus | GB, VC29 Cambridgeshire, Cambridge | Charles Cardale Babington | John Hutton Balfour | 6/1840 | PTH |
| Silene conica | GB, VC90 Angus, Montrose | William Gardiner | Charles Cardale Babington William Hillhouse | | BIRM |
| Silene conica | GB, VC90 Angus, Montrose Links | G Macfarlane | Charles Cardale Babington George Stephen West William West | 5/1843 | BIRM |
| Silene noctiflora | GB, VC26 West Suffolk, Hitcham | Samuel Simpson | Charles Cardale Babington George Stephen West | 3/7/1859 | BIRM |
| Sparganium angustifolium | IE, VCH16 West Galway, Roundstone | Charles Cardale Babington | William Hillhouse | 9/9/1879 | BIRM |
| Sparganium minimum | GB, VC29 Cambridgeshire, Bottisham Fen | Charles Cardale Babington | Cambridge University Hugh Neville Dixon Leslie Beeching Hall | 8/6/1849 | SLBI |
| Spartina alterniflora | GB, VC11 South Hampshire, Southampton | | Charles Cardale Babington George Stephen West W McIvor | 8/1847 | BIRM |
| Spartina maritima | GB, VC11 South Hampshire, Southampton | | Charles Cardale Babington George Stephen West W McIvor | 8/1841 | BIRM |
| Stachys sylvatica x palustris = S. x ambigua | GB, VC34 West Gloucestershire, Durdham Down | Charles Cardale Babington | John Ewbank Leefe | 26/8/1836 | K |
| Stellaria pallida | GB, VC36 Herefordshire, Holme Marsh | Charles Cardale Babington | George Stephen West William West | 16/5/1864 | BIRM |
+ | Stellaria palustris | GB, VC29 Cambridgeshire, Bottisham Fen | Charles Cardale Babington | John Hutton Balfour | 22/5/1840 | PTH |
| Stratiotes aloides | GB, VC27 East Norfolk, Brockdish | | Charles Cardale Babington | 1838 | E |