| Mentha spicata x longifolia = M. x villosonervata | IE, VCH25 Co. Roscommon, Roscommon | Mary McCallum Webster | | 29/6/1962 | CGE |
| Mentha aquatica | IE, VCH13 Co. Carlow, Tullow | Mary McCallum Webster | | 6/9/1957 | K |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH13 Co. Carlow, Milltown | Mary McCallum Webster | | 5/9/1957 | K |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH13 Co. Carlow, Milford | Mary McCallum Webster | | 5/9/1957 | K |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH13 Co. Carlow, Leighlinbridge | Mary McCallum Webster | | 7/9/1957 | K |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH13 Co. Carlow, Bunclody | Mary McCallum Webster | | 4/9/1962 | K |
| Mentha aquatica x spicata = M. x piperita | IE, VCH13 Co. Carlow, Borris | Mary McCallum Webster | | 6/9/1957 | K |
| Mentha suaveolens | IE, VCH12 Co. Wexford, Wilton Castle | Mary McCallum Webster | | 5/8/1957 | K |
| Mentha aquatica x spicata = M. x piperita | IE, VCH12 Co. Wexford, Rathnure | Mary McCallum Webster | | 4/9/1957 | K |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH12 Co. Wexford, Rathnure | Mary McCallum Webster | | 4/9/1957 | K |
| Mentha piperita var. piperita | IE, VCH12 Co. Wexford, Lady's Island | Mary McCallum Webster | | 8/9/1957 | K |
| Lamium purpureum var. hybridum | IE, VCH12 Co. Wexford, Bunclody | Mary McCallum Webster | | 4/9/1962 | K |
| Mentha aquatica | IE, VCH12 Co. Wexford, Bunclody | Mary McCallum Webster | | 4/9/1962 | K |
| Mentha arvensis x aquatica = M. x verticillata | IE, VCH12 Co. Wexford, Bunclody | Mary McCallum Webster | | 5/9/1962 | K |
| Mentha arvensis x spicata = M. x gracilis | IE, VCH12 Co. Wexford, Bunclody | Mary McCallum Webster | | 5/9/1962 | CGE |
| Mentha arvensis x spicata = M. x gracilis | IE, VCH12 Co. Wexford, Bunclody | Mary McCallum Webster | | 4/9/1962 | CGE |
| Teucrium chamaedrys | IE, VCH12 Co. Wexford, Ballycarney | Mary McCallum Webster | | 2/9/1962 | K |
| Carex remota | IE, VCH25,VCH29, Lough Allen | Mary McCallum Webster | | 5/7/1962 | BM |
| Carex strigosa | IE, VCH28,VCH29, Drumkeeran | Mary McCallum Webster | | 5/7/1962 | E |
| Mentha arvensis x spicata = M. x gracilis | IE, VCH12,VCH13, Bunclody | Mary McCallum Webster | | 4/9/1962 | CGE |
| Mentha spicata | GB, VC113 Channel Islands, Jersey, Saint Peters | Mary McCallum Webster | | 26/8/1957 | K |
| Mentha spicata x suaveolens = M. x villosa | GB, VC113 Channel Islands, Jersey, Mourier Valley | Mary McCallum Webster | | 21/8/1957 | K |
| Mentha spicata | GB, VC113 Channel Islands, Jersey | Mary McCallum Webster | | 26/8/1957 | K |
| Mentha suaveolens | GB, VC113 Channel Islands, Jersey | Mary McCallum Webster | | 26/8/1957 | K |
| Veronica filiformis | GB, VC113 Channel Islands, Guernsey,Petit Bot | Mary McCallum Webster | | 23/4/1962 | K |
| Veronica polita | GB, VC113 Channel Islands, Alderney | Mary McCallum Webster | | 18/4/1962 | K |
| Potamogeton gramineus | GB, VC112 Shetland, Loch of Brow | Mary McCallum Webster | | 7/8/1969 | E |
| Triglochin palustris | GB, VC112 Shetland, Dunrossness | Mary McCallum Webster | | 7/8/1969 | E |
| Carex sylvatica | GB, VC109 Caithness, Thrumster | Mary McCallum Webster | | 3/7/1972 | E |
| Carex acutiformis | GB, VC109 Caithness, Reay Burn | Mary McCallum Webster | | 10/7/1968 | BM |
| Carex arenaria | GB, VC109 Caithness, Reay | Mary McCallum Webster | | 10/7/1968 | BM |
| Potamogeton gramineus | GB, VC109 Caithness, Loch Watten | Mary McCallum Webster | | 1/7/1956 | E |
| Taraxacum haworthianum | GB, VC109 Caithness, Keiss | Mary McCallum Webster | | 3/7/1972 | E |
| Carex canescens | GB, VC108 West Sutherland, Sandwood Loch | Mary McCallum Webster | | 1/7/1948 | BM |
| Carex canescens | GB, VC108 West Sutherland, Sandwood Loch | Mary McCallum Webster | | 1948 | BM |
| Carex paniculata | GB, VC108 West Sutherland, Sandwood Loch | Mary McCallum Webster | | 1948 | BM |
| Carex paniculata | GB, VC108 West Sutherland, Sandwood Loch | Mary McCallum Webster | | 1/7/1948 | BM |
| Galeopsis tetrahit | GB, VC108 West Sutherland, Melvich | Mary McCallum Webster | | 24/7/1961 | K |
| Habenaria viride | GB, VC108 West Sutherland, Melness | Mary McCallum Webster | | 20/7/1961 | K |
| Carex echinata | GB, VC108 West Sutherland, Kinlochbervie | Mary McCallum Webster | | 1948 | BM |