This monograph presents a study of the butterfly species that used to be included in the genera Anaea, Coenophlebia, Hypna, Polygrapha, Protogonius, Siderone, and Zaretis. The author and the sponsor both never lived to see the book published, and the manuscript and plates were completely rearranged for publication since they were completed. The text is, however, virtually as Comstock wrote it, except for some simple editorial corrections. Based on the collection of Mr Frank Johnson, who accumulated it over the course of twenty years by his own collecting and by the employment of other collectors, a total 9000 specimens were studied, about half of them from Johnson's collection. The large series of diverse localities made it possible to obtain information on the variation and distribution of species. Additional specimens came from museum collections in the US and South America.