| Equisetum hyemale x variegatum = E. x trachyodon | IE, VCH39 Co. Antrim, Colin Glen | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Augustin Ley | 29/7/1893 | BIRM |
+ | Equisetum hyemale x variegatum = E. x trachyodon | IE, VCH39 Co. Antrim, Colin Glen | Samuel Alexander Stewart | | 22/6/1879 | BIRM |
| Equisetum hyemale x variegatum = E. x trachyodon | IE, VCH39 Co. Antrim, Colin Glen | William Mateer | Harold Stuart Thompson Thomas Clark William Mateer | 5/1847 | BIRM |
| Polystichum setiferum | IE, VCH39 Co. Antrim, Colin Glen | William Mateer | Harold Stuart Thompson Thomas Clark William Mateer | 7/1847 | BIRM |
+ | Hieracium basalticola | IE, VCH39 Co. Antrim, Cave Hill, Belfast | Claude Evrard Aldington Andrews | | 25/7/1956 | BIRM |
+ | Hieracium orcadense | IE, VCH39 Co. Antrim, Cave Hill, Belfast | Claude Evrard Aldington Andrews | | 25/7/1956 | BIRM |
+ | Hieracium subcrocatum | IE, VCH39 Co. Antrim, Cave Hill, Belfast | Claude Evrard Aldington Andrews | | 2/8/1956 | BIRM |
| Orobanche alba | IE, VCH39 Co. Antrim, Cave Hill, Belfast | Samuel Alexander Stewart | Augustin Ley | 8/7/1871 | BIRM |
| Orobanche alba | IE, VCH39 Co. Antrim, Cave Hill, Belfast | Alexander Carroll Maingay | George Stephen West Alexander Carroll Maingay | 8/1856 | BIRM |
| Orobanche alba | IE, VCH39 Co. Antrim, Cave Hill, Belfast | William Mateer | Thomas Clark William Mateer | 7/1847 | BIRM |
| Orobanche alba | IE, VCH39 Co. Antrim, Cave Hill, Belfast | William West | George Stephen West William West | 8/1892 | BIRM |
| Rosa sherardii | IE, VCH39 Co. Antrim, Carnlough | Coslett Herbert Waddell | Botanical Exchange Club of The British Isles Coslett Herbert Waddell | 9/8/1910 | BIRM |
| Elatine hydropiper | IE, VCH39 Co. Antrim, Belfast,Lagan Canal | William Mateer | George Stephen West | 8/1847 | BIRM |
| Equisetum hyemale x variegatum = E. x trachyodon | IE, VCH39 Co. Antrim, Belfast,Colin Glen | Samuel Alexander Stewart | Harold Stuart Thompson | 22/6/1879 | BIRM |
| Digitaria ischaemum | IE, VCH39 Co. Antrim, Belfast | | London Botanical Exchange Club Robert Large Baker | 13/9/1872 | BIRM |
| Equisetum pratense | IE, VCH39 Co. Antrim, Belfast | Coslett Herbert Waddell | Watson Botanical Exchange Club Coslett Herbert Waddell Harold Stuart Thompson | 5/1901 | BIRM |
| Potamogeton praelongus x crispus = P. x undulatus | IE, VCH39 Co. Antrim, Belfast | George Taylor | | 9/1952 | BIRM |
| Senecio jacobaea | IE, VCH39 Co. Antrim, Belfast | James Walter White | Watson Botanical Exchange Club Harold Stuart Thompson James Walter White | 27/7/1926 | BIRM |
| Alchemilla xanthochlora | IE, VCH39 Co. Antrim, Ballintoy | Charles Bailey | Charles Bailey | 11/7/1896 | BIRM |
| Angelica archangelica | IE, VCH39 Co. Antrim, Ballintoy IE, VCH39 Co. Antrim, Carrickarade Island | Charles Bailey | Botanical Exchange Club of The British Isles Charles Bailey | 11/7/1896 | BIRM |
| Callitriche hermaphroditica | IE, VCH39 Co. Antrim, Antrim | William Mateer | Harold Stuart Thompson Thomas Clark | | BIRM |
+ | Hieracium anglicum | IE, VCH39 Co. Antrim, Antrim | Claude Evrard Aldington Andrews | | 21/7/1956 | BIRM |
+ | Hieracium anglicum | IE, VCH39 Co. Antrim, Antrim | Claude Evrard Aldington Andrews | | 23/7/1956 | BIRM |
+ | Hieracium anglicum | IE, VCH39 Co. Antrim, Antrim | Claude Evrard Aldington Andrews | | 24/7/1956 | BIRM |
+ | Hieracium strictiforme | IE, VCH38 Co. Down, Tollymore Forest Park | Claude Evrard Aldington Andrews | | 1/8/1956 | BIRM |
| Limonium humile | IE, VCH38 Co. Down, Strangford Lough | Richard Charles L'Estrange Burges | | 11/8/1949 | BIRM |
| Puccinellia maritima | IE, VCH38 Co. Down, Strangford Lough | Robert Lloyd Praeger | Harold Stuart Thompson | 10/7/1905 | BIRM |
| Linaria repens | IE, VCH38 Co. Down, Spelgo Mountain | Frederick Janson Hanbury | Augustin Ley | 7/1891 | BIRM |
| Callitriche hamulata | IE, VCH38 Co. Down, Sheepbridge | Henry William Lett | Watson Botanical Exchange Club Harold Stuart Thompson Henry William Lett | 6/6/1901 | BIRM |
| Ranunculus penicillatus subsp. pseudofluitans | IE, VCH38 Co. Down, Sheepbridge | Henry William Lett | Watson Botanical Exchange Club Harold Stuart Thompson Henry William Lett | 6/6/1901 | BIRM |
| Circaea lutetiana x alpina = C. x intermedia | IE, VCH38 Co. Down, Saintfield | Coslett Herbert Waddell | Watson Botanical Exchange Club Coslett Herbert Waddell Harold Stuart Thompson | | BIRM |
| Mentha spicata | IE, VCH38 Co. Down, Saintfield Cultivated | Coslett Herbert Waddell | Watson Botanical Exchange Club Augustin Ley Coslett Herbert Waddell | 7/1902 | BIRM |
| Polygonum aviculare | IE, VCH38 Co. Down, Saintfield | Coslett Herbert Waddell | Watson Botanical Exchange Club Augustin Ley Coslett Herbert Waddell | 8/1909 | BIRM |
| Potamogeton obtusifolius | IE, VCH38 Co. Down, Saintfield | Coslett Herbert Waddell | Coslett Herbert Waddell Harold Stuart Thompson | 9/1896 | BIRM |
| Ranunculus peltatus | IE, VCH38 Co. Down, Saintfield | Coslett Herbert Waddell | Watson Botanical Exchange Club Augustin Ley Coslett Herbert Waddell | 30/6/1909 | BIRM |
| Salix daphnoides | IE, VCH38 Co. Down, Saintfield | Coslett Herbert Waddell | Botanical Exchange Club of The British Isles Augustin Ley Coslett Herbert Waddell | 4/1909 to 8/1909 | BIRM |
| Valeriana officinalis | IE, VCH38 Co. Down, Saintfield | Coslett Herbert Waddell | Coslett Herbert Waddell Harold Stuart Thompson | 8/1895 | BIRM |
| Viola tricolor subsp. saxatilis | IE, VCH38 Co. Down, Saintfield | Coslett Herbert Waddell | Watson Botanical Exchange Club Augustin Ley Coslett Herbert Waddell | 4/10/1910 | BIRM |
| Camelina alyssum | IE, VCH38 Co. Down, Newtownards | Edward Francis Linton | Augustin Ley | 7/1871 | BIRM |
| Camelina sativa | IE, VCH38 Co. Down, Newtownards | William Richardson Linton | Augustin Ley | 7/1871 | BIRM |