+ | Euphrasia nemorosa x brevipila | IE, Nantenan, near Askeaton, co. Limerick. [H8] | Coslett Herbert Waddell | | 11/9/1905 | MANCH |
| Euphrasia salisburgensis | IE, VCH8 Co. Limerick, Askeaton | Coslett Herbert Waddell | Watson Botanical Exchange Club Coslett Herbert Waddell | 7/1900 | SLBI |
| Euphrasia salisburgensis | IE, VCH8 Co. Limerick, Askeaton | Coslett Herbert Waddell | Botanical Exchange Club of The British Isles Augustin Ley Coslett Herbert Waddell | 7/1908 | BIRM |
| Euphrasia salisburgensis | IE, VCH8 Co. Limerick, Ballynort nr. Askeaton | Coslett Herbert Waddell | Watson Botanical Exchange Club Augustin Ley Coslett Herbert Waddell | 7/1908 | BIRM |
| Euphrasia salisburgensis | IE, VCH8 Co. Limerick, Askeaton,Nantinan | Coslett Herbert Waddell | Allan Octavian Hume | 11/8/1905 | SLBI |
| Fallopia convolvulus var. subalatum | IE, VCH38 Co. Down, grey abbey | Coslett Herbert Waddell | Watson Botanical Exchange Club William Robert Sherrin | 9/1914 | SLBI |
| Galium album | IE, VCH38 Co. Down, Saintfield | Coslett Herbert Waddell | William Robert Sherrin | 5/1896 | SLBI |
+ | Helianthemum oelandicum subsp. levigatum | GB, VC65 North-west Yorkshire, Middleton in Teesdale,Cronkley Fell | Henry Elliott Fox | Botanical Exchange Club of The British Isles Coslett Herbert Waddell Elizabeth Anne Lomax | 2/7/1886 | MANCH |
| Hieracium hypochaeroides | GB, VC69 Westmorland, Kendal | Coslett Herbert Waddell | Coslett Herbert Waddell | 7/1895 | ABS |
| Hieracium sect. Hieracium | IE, VCH38 Co. Down, Saintfield, Rowallane | Coslett Herbert Waddell | Allan Octavian Hume Coslett Herbert Waddell | 12/7/1904 | SLBI |
| Inula salicina | IE, VCH10 North Tipperary, Lough Derg | C F Lilly | Watson Botanical Exchange Club Augustin Ley Coslett Herbert Waddell | 7/1895 | BIRM |
| Isoetes lacustris | IE, VCH20,VCH21, Lough Bray Upper | Coslett Herbert Waddell | Coslett Herbert Waddell Harold Stuart Thompson | 29/7/1893 | BIRM |
| Lathyrus palustris | IE, VCH37 Co. Armagh, Lough Neagh | S A Blenan | Watson Botanical Exchange Club Coslett Herbert Waddell William Robert Sherrin | 5/7/1865 | SLBI |
| Lemna gibba | GB, VC37 Worcestershire, Ripple | Coslett Herbert Waddell | Watson Botanical Exchange Club Coslett Herbert Waddell | 8/1898 | SHYB |
| Lemna gibba | IE, VCH38 Co. Down, Downpatrick | Coslett Herbert Waddell | Watson Botanical Exchange Club Coslett Herbert Waddell Harold Stuart Thompson | 8/1896 | BIRM |
| Leonurus cardiaca | GB, VC54 North Lincolnshire, Ingoldmells | Helen M Nash | Coslett Herbert Waddell | 11/9/1913 | K |
| Limonium vulgare x humile = L. x neumanii | IE, VCH38 Co. Down, Portaferry | Coslett Herbert Waddell | Allan Octavian Hume Coslett Herbert Waddell | 9/1905 | SLBI |
| Linum catharticum | IE, VCH38 Co. Down, Saintfield | | Coslett Herbert Waddell | 7/1916 | GALW |
| Lotus corniculatus | IE, VCH38 Co. Down, Ballykinlar | Coslett Herbert Waddell | Watson Botanical Exchange Club Coslett Herbert Waddell | 9/1900 | ABS |
| Mentha | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | Coslett Herbert Waddell | 10/1894 | K |
| Mentha aquatica x spicata = M. x piperita | IE, VCH39 Co. Antrim, Carnmoney | Coslett Herbert Waddell | Watson Botanical Exchange Club Coslett Herbert Waddell Spencer Henry Bickham | 8/1895 | CGE |
| Mentha aquatica x spicata = M. x piperita | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | Alexander Goodman More Coslett Herbert Waddell | 2/10/1894 | DBN |
| Mentha aquatica x spicata = M. x piperita | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | | 2/10/1894 | DBN |
| Mentha arvensis x aquatica x spicata = M. x smithiana | IE, VCH38 Co. Down, Bryansford Cultivated | Coslett Herbert Waddell | Watson Botanical Exchange Club Coslett Herbert Waddell | 8/1895 | LIV |
| Mentha arvensis x aquatica x spicata = M. x smithiana | IE, VCH38 Co. Down, Saintfield Cultivated | Coslett Herbert Waddell | Coslett Herbert Waddell | 9/1894 | DBN |
| Mentha spicata | IE, VCH38 Co. Down, Saintfield Cultivated | Coslett Herbert Waddell | Watson Botanical Exchange Club Augustin Ley Coslett Herbert Waddell | 7/1902 | BIRM |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | Coslett Herbert Waddell | 2/10/1894 | CGE |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul Cultivated | Coslett Herbert Waddell | | 9/1895 | DBN |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul Cultivated | Coslett Herbert Waddell | Coslett Herbert Waddell Robert Lloyd Praeger | 9/1894 | DBN |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | National Museum Ireland Alexander Goodman More Coslett Herbert Waddell | 2/10/1894 | DBN |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | Alexander Goodman More Coslett Herbert Waddell | 2/10/1894 | DBN |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | | 2/10/1894 | DBN |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | Coslett Herbert Waddell | 9/1894 | DBN |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul Cultivated | Coslett Herbert Waddell | Alexander Goodman More Coslett Herbert Waddell | 21/9/1894 | DBN |
| Mentha spicata x suaveolens = M. x villosa var. alopecuroides | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | | 2/10/1894 | LIV |
| Mentha spicata x suaveolens = M. x villosa | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | Coslett Herbert Waddell | 2/10/1894 | K |
| Mentha suaveolens x longifolia = M. x rotundifolia | IE, VCH38 Co. Down, Saul Cultivated | Coslett Herbert Waddell | Coslett Herbert Waddell William Hunt Painter | 9/1894 | ABS |
+ | Mentha suaveolens x longifolia = M. x rotundifolia | IE, VCH38 Co. Down, Saul | Coslett Herbert Waddell | Charles Bailey | 8/1895 | MANCH |
+ | Muscari neglectum | GB, VC15 East Kent, Luddenham | Frederic Henry Ward | Coslett Herbert Waddell Elizabeth Anne Lomax | 18/5/1887 | MANCH |
| Myosotis ramosissima | IE, VCH38 Co. Down, Kirkistown | Coslett Herbert Waddell | Belfast | 5/1894 | GALW |