The four species in this genus resemble each other so closely that great difficulty is experienced by many workers in separating them. Records, therefore, tend to be somewhat unreliable and have even been submitted to us sometimes as "Epirritas various"! A few constant characters may therefore prove of some use, especially to beginners. [...] The four species, E. autumnata, E. filigrarnmaria, E. dilutata and E. christyi, fall naturally into two groups, E. auturnnata and E. fiigrarnrnaria forming a closely related pair as also do E. dilutata and E. chrisiyi. All can be separated fairly easily by the examination of their genitalia, but since this method is not readily available to the collector with no more than a hand lens to help him, it is necessary to consider other characters. E. filigrarnrnaria is most easily separated from the other three by reason of its smaller size, narrow, more pointed wings and greater intensity of the cross bands on both the fore- and (usually) the hindwings. These features, taken together with its special habitat, Calluna heath (the caterpillar feeding entirely on heather and bilberry), will in most cases clinch identification. It is usually the first to appear, emerging in August and remaining on the wing into early September. The other three species may prove more of a problem, especially if they have been on the wing for some time and become rubbed or are, genetically, not very well marked. If the bands can be detected the fourth or post-median band or fascia should be noted. In E. dilutata this band shows little arching at the costal end so that it frequently touches and may even merge with the discoidal spot. In E. auturnnata and E. christyi the band swings outwards avoiding the discoidal spot altogether. In E. auturnnata the band makes a sharp right-angled bend behind the spot whilst in E. christyi, the band makes a gentle curved path round the spot. In addition the wing of E. autumnata is very glossy and slightly larger than either dllutata or christyi. The wings of the last two are not so glossy if at all. Of the three, christyi is usually slightly the smallest and its background colour usually whiter than the others. An additional character, not pointed out previously to our knowledge is the shape of the costa. In E. christyi this has a characteristic hump near the base which is not present in any of the others where the costa is more uniformly arched. E. autumnata takes to the wing only a week or two after E. filigramrnaria and continues flying throughout September and early October. In the north-east it is usually over by the middle of October but in some years it may go on until the end of the month. E. dllutata is on the wing for a longer period than any of the others and is usually the most abundant in our [county]. It starts at the beginning of October and goes right through to the end of November. We have never found christyi on the wing until the first week of November. Although the three caterpillars are somewhat similar, and variable to the same extent as their imagines, their feeding habits are somewhat different Alder seems to be the preferred foodplant of E. autumnata with Birch being used almost as frequently. We have never found them on any other foodplant. E. dilutata prefers Oak but can also be found on a wide variety of other trees and shrubs such as Birch, Hawthorn, Blackthorn and Hazel. E. christyi seems to be most fond of Wych Elm, but Common Elm, SaIix species and Honeysuckle are also used, especially if growing in the vicinity of Wych Elm. For those who like to breed their moths from the caterpillars beaten in the field, it is easy to do so by using Hawthorn upon which all four species will happily feed, pupate and produce healthy imagines. If all these factors are taken together there should be some chance of a correct identification.