| Mespilus germanica | GB, VC2 East Cornwall, Saltash | Thomas Richard Archer Briggs | Augustin Ley | 27/5/1871 | BIRM |
| Mespilus germanica | GB, VC3 South Devon, Battisborough | Thomas Richard Archer Briggs | Augustin Ley Thomas Richard Archer Briggs | 26/5/1868 20/8/1868 | BIRM |
| Mespilus germanica | GB, VC39 Staffordshire, Salt | Thomas Richard Archer Briggs | Augustin Ley | 14/5/1888 | BIRM |
| Odontites vernus | GB, VC3 South Devon, Plymouth | Thomas Richard Archer Briggs | Augustin Ley | 19/6/1872 | BIRM |
| Orobanche minor var. maritima | GB, VC2 East Cornwall, Seaton | Thomas Richard Archer Briggs | Augustin Ley | 12/6/1876 | BIRM |
| Orobanche minor var. maritima | GB, VC2 East Cornwall, Whitsand Bay | Thomas Richard Archer Briggs | Augustin Ley | 24/6/1875 | BIRM |
| Orobanche minor var. maritima | GB, VC2 East Cornwall, Whitsand Bay | Thomas Richard Archer Briggs | John Ralfs | 7/1875 | SLBI |
| Persicaria lapathifolia | GB, VC3 South Devon, Ivybridge | Thomas Richard Archer Briggs | Frederick Townsend | 15/9/1877 | SLBI |
+ | Physospermum cornubiense | VC 2 | Thomas Richard Archer Briggs | Charles Bailey | 7/7/1874 | MANCH |
+ | Physospermum cornubiense | VC 2 | Thomas Richard Archer Briggs | Charles Bailey | 6/8/1874 | MANCH |
+ | Physospermum cornubiense | GB, VC3 South Devon, Blaxton | Thomas Richard Archer Briggs | Charles Bailey | 7/1868 | MANCH |
| Polycarpon tetraphyllum | GB, VC3 South Devon, King's Tamerton, Plymouth | Thomas Richard Archer Briggs | George Stephen West | 5/1869 | BIRM |
| Polycarpon tetraphyllum | GB, VC3 South Devon, Plymouth | Thomas Richard Archer Briggs | William Hadden Beeby | 5/1869 | SLBI |
| Polygonum aviculare | GB, VC3 South Devon, Crabtree | Thomas Richard Archer Briggs | Augustin Ley | 10/9/1877 | BIRM |
| Polygonum aviculare | GB, VC3 South Devon, Wembury | Thomas Richard Archer Briggs | Frederick Townsend | 2/9/1867 | SLBI |
| Polygonum rurivagum | GB, VC3 South Devon, Plymouth | Thomas Richard Archer Briggs | Augustin Ley | 25/8/1868 | BIRM |
| Polygonum rurivagum | GB, VC3 South Devon, Plymouth | Thomas Richard Archer Briggs | Augustin Ley | 25/8/1868 | BIRM |
| Potamogeton polygonifolius | GB, VC3 South Devon, Erme Valley | Thomas Richard Archer Briggs | | 6/1876 | E |
| Prunus spinosa x domestica = P. x fruticans | GB, VC2 East Cornwall, Torpoint | Thomas Richard Archer Briggs | Augustin Ley | 17/4/1876 | BIRM |
| Prunus spinosa x domestica = P. x fruticans | GB, VC2 East Cornwall, Torpoint | Thomas Richard Archer Briggs | Augustin Ley | 19/9/1876 | BIRM |
+ | Puccinellia fasciculata | GB, VC3 South Devon, Crabtree | Thomas Richard Archer Briggs | Charles Bailey | 26/6/1875 | MANCH |
| Puccinellia fasciculata | GB, VC3 South Devon, Crabtree | Thomas Richard Archer Briggs | Botanical Exchange Club of The British Isles Robert Large Baker | 26/6/1875 | BIRM |
+ | Pyrus cordata | GB, VC2 East Cornwall, Saint John | Thomas Richard Archer Briggs | | 1877 | BIRM |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 18/5/1881 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 4/5/1871 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey Elizabeth Anne Lomax | 13/8/1875 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 11/5/1877 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 13/8/1876 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 13/9/1881 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 18/5/1881 to 13/9/1881 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 18/5/1881 to 13/9/1881 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 30/5/1879 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 13/8/1876 | MANCH |
+ | Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Charles Bailey | 18/5/1881 | MANCH |
| Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | | 13/8/1875 | SLBI |
| Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | William Hadden Beeby | 13/8/1875 | SLBI |
| Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Botanical Exchange Club of The British Isles William Hadden Beeby | 13/9/1881 | SLBI |
| Pyrus cordata | GB, VC3 South Devon, Egg Buckland | Thomas Richard Archer Briggs | Botanical Exchange Club of The British Isles William Hunt Painter | 18/5/1881 | ABS |
| Pyrus cordata | GB, VC3 South Devon, Estover | Thomas Richard Archer Briggs | | 9/5/1870 | BIRM |
| Pyrus cordata | GB, VC3 South Devon, Estover | Thomas Richard Archer Briggs | | 4/5/1871 | BIRM |