| Arenaria ciliata | IE, VCH28 Co. Sligo, Kings Mountain | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Allan Octavian Hume | 18/7/1879 | SLBI |
| Dryas octopetala | IE, VCH28 Co. Sligo, Benbulben | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles | 16/7/1879 | SLBI |
| Polygala vulgaris | IE, VCH28 Co. Sligo, Benbulben | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Augustin Ley | 16/7/1879 | BIRM |
| Polygala vulgaris | IE, VCH28 Co. Sligo, Benbulben | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Edward Francis Linton | 16/7/1879 | SLBI |
| Equisetum hyemale x variegatum = E. x trachyodon | IE, VCH39 Co. Antrim, Belfast,Colin Glen | Samuel Alexander Stewart | Harold Stuart Thompson | 22/6/1879 | BIRM |
+ | Equisetum hyemale x variegatum = E. x trachyodon | IE, VCH39 Co. Antrim, Colin Glen | Samuel Alexander Stewart | | 22/6/1879 | BIRM |
| Barbarea intermedia | IE, VCH39 Co. Antrim, Whitewell, Belfast | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Augustin Ley | 15/6/1879 | BIRM |
| Zannichellia palustris | IE, VCH39 Co. Antrim, Belfast | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Samuel Alexander Stewart | 12/8/1878 | ABS |
| Saxifraga umbrosa x hirsuta = S. x geum | IE, VCH1 South Kerry, Brandon Mountain | Samuel Alexander Stewart | Arthur Bennett | 18/7/1878 | SLBI |
| Adiantum capillus-veneris | IE, VCH9 Co. Clare, Black Head | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Augustin Ley Samuel Alexander Stewart | 15/7/1878 | BIRM |
| Daboecia cantabrica | IE, Mayo, Uggool | Samuel Alexander Stewart | Robert Large Baker | 19/8/1877 | BIRM |
| Daboecia cantabrica | IE, VCH16 West Galway, Lough Uggool | Samuel Alexander Stewart | William Hadden Beeby | 18/8/1877 | SLBI |
| Najas flexilis | IE, VCH16 West Galway, Roundstone | Samuel Alexander Stewart | Augustin Ley | 15/8/1877 | BIRM |
| Najas flexilis | IE, VCH16 West Galway, Roundstone | Samuel Alexander Stewart | Harold Stuart Thompson | 15/8/1877 | BIRM |
+ | Calamagrostis stricta | IE, VCH39 Co. Antrim, Lough Neagh | Samuel Alexander Stewart | Botanical Exchange Club Charles Bailey | 30/6/1877 | MANCH |
+ | Calamagrostis stricta | IE, VCH39 Co. Antrim, Lough Neagh | Samuel Alexander Stewart | Botanical Exchange Club Charles Bailey | 30/6/1877 | MANCH |
| Valerianella carinata | IE, VCH38 Co. Down, Dundonald | Samuel Alexander Stewart | Augustin Ley | 19/6/1877 | BIRM |
| Zannichellia palustris | IE, VCH38,VCH39, Belfast | Samuel Alexander Stewart | Augustin Ley | 23/8/1876 | BIRM |
| Zannichellia polycarpa | IE, VCH38,VCH39, Belfast | Samuel Alexander Stewart | William Hadden Beeby | 23/8/1876 | SLBI |
| Carex arenaria | IE, VCH38 Co. Down | Samuel Alexander Stewart | William Hadden Beeby | 6/1876 | SLBI |
| Carex arenaria | IE, VCH38 Co. Down | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Frederick Janson Hanbury | 6/1876 | BM |
| Carex arenaria | IE, VCH38 Co. Down | Samuel Alexander Stewart | Edward Francis Linton | 6/1876 | BM |
+ | Carex divisa | IE, VCH38 Co. Down | Samuel Alexander Stewart | Botanical Exchange Club Charles Bailey | 6/1876 | MANCH |
| Carex arenaria | IE, VCH38 Co. Down, Co. Down | Samuel Alexander Stewart | Botanical Exchange Club of The British Isles Augustin Ley | 6/1876 | BIRM |
| Equisetum variegatum | IE, VCH19,VCH22, Maynooth | Samuel Alexander Stewart | Augustin Ley | 15/5/1876 | BIRM |
| Arctostaphylos uva-ursi | IE, VCH9 Co. Clare, Black Head | Samuel Alexander Stewart | Augustin Ley | 13/5/1876 | BIRM |
| Dryas octopetala | IE, VCH9 Co. Clare, Black Head | Samuel Alexander Stewart | | 12/5/1876 | SLBI |
| Gentiana verna | IE, VCH9 Co. Clare, blackhead | Samuel Alexander Stewart | William Hadden Beeby | 12/5/1876 | SLBI |
| Saxifraga umbrosa | IE, VCH16 West Galway, Ben Lettery | Samuel Alexander Stewart | William Hadden Beeby Arthur Bennett | 10/5/1876 | SLBI |
| Saxifraga umbrosa var. punctata | IE, VCH16 West Galway, Connemara | Samuel Alexander Stewart | Augustin Ley | 10/5/1876 | BIRM |
| Saxifraga umbrosa x spathularis = S. x urbium | IE, VCH16 West Galway, Connemara | Samuel Alexander Stewart | Charles Bailey | 10/5/1876 | MANCH |
+ | Hymenophyllum wilsonii | IE, VCH16 West Galway, Twelve Pins,Bengower | Samuel Alexander Stewart | Charles Bailey | 10/5/1876 | MANCH |
| Arctostaphylos uva-ursi | IE, VCH9 Co. Clare, Black Head | Samuel Alexander Stewart | Robert Large Baker | 5/1876 | BIRM |
| Rosa spinosissima x canina = R. x hibernica | IE, VCH39 Co. Antrim, Belfast | Samuel Alexander Stewart | | 12/7/1875 | SLBI |
+ | Potamogeton praelongus | IE, VCH39 Co. Antrim, Belfast,Lagan Canal | Samuel Alexander Stewart | Alfred Fryer Charles Bailey | 23/6/1873 | MANCH |
| Carex spicata | IE, VCH39 Co. Antrim, Greencastle | Samuel Alexander Stewart | Edward Francis Linton | 19/6/1873 | BM |
| Mentha aquatica x spicata = M. x piperita | IE, VCH39 Co. Antrim, Carnmoney | Samuel Alexander Stewart | Science & Art Museum Dublin | 14/9/1872 | DBN |
| Equisetum hyemale x variegatum = E. x trachyodon | IE, VCH39 Co. Antrim, Colin Glen | Samuel Alexander Stewart | Augustin Ley | 1/7/1872 | BIRM |
| Equisetum hyemale x variegatum = E. x trachyodon | IE, VCH39 Co. Antrim, Colin Glen | Samuel Alexander Stewart | | 1/7/1872 | BON |
| Carex distans | IE, VCH39 Co. Antrim, Black Head | Samuel Alexander Stewart | | 29/6/1872 | BON |