A lepldopterlst gives his account of an exciting discovery of a population of Lemonia dumi. This moth Is very rare In the Netherlands and has not been sighted in this country since 1956. A total of 81 specimens of L. dumi were observed over a two-week period In the second half of October 1994. The site consisted of a pine-wood edge on sandy soil with sparse grass vegetation. How this distinct population has remained unnoticed for so long Is a mystery.