We have mapped at 2 km square level as that seems to provide the best combination of detail and visibility. Recording has been divided into three periods as follows: The historical work done up to 1960. Most of this was before the era of the light trap, and was based on collections of dead specimens. The results have been published as detailed papers or within more general publications such as Baynes (1964) A Revised Catalogue of Irish Macrolepidoptera (butterflies and moths). Classey, Hampton. Many of these records are not sufficiently detailed to allow mapping, and statements such as “common” for species which we now regard as rare, are frustratingly vague and difficult to test. Those records which are precise enough to allow us to allocate a 2 km. square, are mapped with a yellow dot. Between 1960 and 1990 some work was continued by Danny O’Sullivan, now on the mainland at Greencastle. C. de Mornay did a lot of trapping at his home near Manorcunningham, but it seems very little elsewhere. Other people continued to provide Baynes with a few records of interesting finds. Some of these were resident in the county, or regular visitors, but their records are mostly from very limited areas. Since 1990, the present generation of enthusiasts has been spreading the net more widely. Our records are shown in dark green.