Habitats ofLycaeides argyrognomon Bgstr. are described. The most ritualized courtship comprises: male approaching, male fluttering around, female mate refusal posture, female escape flight, sexual chase, female alighting, male fluttering around, female receptive posture, parallel position, male abdomen-bending, male attaching and copulatory position. Field experiments have shown that the refusal posture of mated females is released by odors from the male wings. In unfertilized females this behavior is inhibited by male odor signals. In SEM pictures of the androconial scales of dried specimen, holes and fissures in the upper scale lamella were found. Experiments with models indicate the existence of behavior-releasing odors from the female wings though the females lack scent scales comparable to those of the males. The female scents provoke the whole terminal sequence of the male courtship behavior when combined with a suitable visual object. The volatile material has been analyzed by capillary gas chromatography and mass spectrometry. Wings of males were found to contain nonanal, hexadecyl acetate, and a cyclic sesquiterpene alcohol, tentatively identified as torreyol (δ-cadinol).