The sixth of a seven-part series devoted to the true butterflies (superfamily Paplionoidea), concentrating on the Riodinidae family. With the publication of this volume, the author has attempted to fill a large number of gaps with new descriptions and with accurate coloured plates not known at the time of Seitz and his contemporaries. However he has scanned collections, both public and private, and in many instances been forced to leave well alone many apparently undescribed taxa because of insufficient material or because of its indifferent quality. Although he has treated around 1200 species, he is quite aware that there probably remain another 100-150 taxa which need to be described and published sometime in the future. Nevertheless this volume remains the only one of its kind devoted to the Riodinidae, and notwithstanding its shortcomings will be of inestimable use to the serious lepidopterist.