| Ajuga reptans | IE, VCH39 Co. Antrim, Lough Neagh | David Allardice Webb | Trinity College, Dublin | 13/5/1950 | K |
| Carex arenaria | IE, VCH9 Co. Clare, Liscannor | Peter Sherlock Wyse Jackson | Irish Biogeographical Society Trinity College, Dublin | 24/6/1979 | GALW |
| Carex hostiana x viridula = C. x fulva | IE, VCH9 Co. Clare, Mullagh More | Peter Sherlock Wyse Jackson | Irish Biogeographical Society Trinity College, Dublin | 19/6/1979 | GALW |
| Carex hostiana x viridula = C. x fulva | IE, VCH9 Co. Clare, Mullagh More | Peter Sherlock Wyse Jackson | Irish Biogeographical Society Trinity College, Dublin | 19/6/1979 | GALW |
| Carex remota | IE, VCH21 Co. Dublin, Colganstown | John Parnell Michael B Wyse Jackson | Trinity College, Dublin | 6/1987 | E |
| Carum verticillatum | IE, Kerry, Killarney | Harvey | Trinity College, Dublin Harold Stuart Thompson Thomas Clark William Collins | | BIRM |
| Cicendia filiformis | IE, VCH16 West Galway, Connemara | William Collins | Trinity College, Dublin Harold Stuart Thompson Thomas Clark William Henry Harvey | | BIRM |
| Cochlearia | IE, VCH35 West Donegal, Dungloe | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 13/7/1980 | GALW |
| Cochlearia anglica | IE, VCH4,VCH5, Tramore | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 28/6/1929 | GALW |
| Cochlearia anglica | IE, VCH6 Co. Waterford, River Blackwater | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 21/6/1980 | GALW |
| Cochlearia anglica | IE, VCH8 Co. Limerick, Limerick | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 10/6/1980 | GALW |
| Cochlearia anglica | IE, VCH40 Co. Londonderry, Lough Foyle | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 10/7/1980 | GALW |
| Cochlearia anglica x officinalis = C. x hollandica | IE, VCH6 Co. Waterford, Annestown | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 28/6/1979 | GALW |
| Cochlearia anglica x officinalis = C. x hollandica | IE, VCH6 Co. Waterford, County Waterford | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 28/6/1979 | GALW |
| Cochlearia anglica x officinalis = C. x hollandica | IE, East Galway, Oranmore | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 14/7/1979 | GALW |
| Cochlearia anglica x officinalis = C. x hollandica | IE, VCH28 Co. Sligo, Ballysadare Bay | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 10/7/1979 | GALW |
| Cochlearia danica | IE, VCH6 Co. Waterford, Kilfarrasy | Micheline Joan Sheehy Skeffington | Trinity College, Dublin | 18/5/1980 | GALW |
| Cochlearia danica | IE, VCH16 West Galway, Spiddal | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 18/4/1980 | GALW |
| Cochlearia danica | IE, VCH20 Co. Wicklow, Kilcoole | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 19/5/1979 | GALW |
| Cochlearia danica | IE, VCH21 Co. Dublin, Dublin | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 9/5/1980 | GALW |
| Cochlearia danica | IE, VCH21 Co. Dublin, Howth | Micheline Joan Sheehy Skeffington | Trinity College, Dublin | 9/6/1979 | GALW |
| Cochlearia officinalis | IE, VCH20 Co. Wicklow, Greystones | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 6/1979 | GALW |
| Cochlearia officinalis | IE, VCH20 Co. Wicklow, Wicklow | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 19/5/1979 | GALW |
| Cochlearia officinalis | IE, VCH21 Co. Dublin, Donabate | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 3/6/1979 | GALW |
| Cochlearia officinalis | IE, VCH21 Co. Dublin, Sutton | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 26/8/1979 | GALW |
| Cochlearia officinalis | IE, VCH35 West Donegal, Dungloe | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 13/7/1980 | GALW |
| Cochlearia officinalis | IE, VCH39 Co. Antrim, Giants Causeway | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 9/7/1980 | GALW |
| Cochlearia officinalis | IE, VCH39 Co. Antrim, Torr Head | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 9/7/1980 | GALW |
| Cochlearia officinalis subsp. scotica | IE, VCH9 Co. Clare, Ballyvaghan | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 22/6/1979 | GALW |
| Cochlearia officinalis subsp. scotica | IE, VCH39 Co. Antrim, Cushendun | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 8/7/1980 | GALW |
| Cochlearia pyrenaica subsp. alpina | IE, VCH7,VCH8, Lough Curra | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 16/8/1929 | GALW |
| Cochlearia pyrenaica subsp. alpina | IE, VCH1 South Kerry, Lough Googh | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 17/6/1980 | GALW |
| Cochlearia scotica | IE, VCH35 West Donegal, Dungloe | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 13/7/1980 | GALW |
| Cyperus longus | IE | Harvey | Trinity College, Dublin Harold Stuart Thompson Thomas Clark William Collins | | BIRM |
| Daboecia cantabrica | IE, VCH16 West Galway, Connemara | William Henry Harvey | Trinity College, Dublin Harold Stuart Thompson Thomas Clark | | BIRM |
| Erica erigena | IE | William Collins | Trinity College, Dublin Harold Stuart Thompson Thomas Clark | | BIRM |
| Erica mackaiana | IE, VCH16 West Galway, Connemara | William Collins | Trinity College, Dublin Harold Stuart Thompson Thomas Clark William Richardson Linton | 1838 | BIRM |
| Erica mackaiana | IE, VCH35 West Donegal, Upper Lough Nacung | David Allardice Webb | Trinity College, Dublin | 2/8/1953 | SLBI |
| Euphrasia | IE, VCH9 Co. Clare, Liscannor | Peter Sherlock Wyse Jackson | Trinity College, Dublin | 21/6/1974 | GALW |
| Lamium album | IE, VCH22 Meath, Trim | David Allardice Webb | Trinity College, Dublin | 29/5/1950 | K |