ABSTRACTAnalysis of the known and recently discovered differentiation patterns of 58 forest butterfly species (of the total 66) in the tribe Heliconiini, including over 300 races and forms, has led to the drawing of a map of core areas for evolution in the group. The majority of these are not isolated by any obvious modern physiogeographic barriers to dispersal of these butterflies, and probably correspond to forest refugia during the two or three most recent Quaternary dry periods. The map is in good accord with the results of similar studies in other groups of animals (forest vertebrates and invertebrates) and in forest trees, but indicates a larger number of significant operative refugia (38) than other analyses. Bases for the understanding of differentiation patterns in polytypic continental species are developed, in accord with the refuge theory and using intensive and extensive data on local monomorphic populations and secondary contact zones between differentiated forms. The known forms discussed include:Dione juno miraculosaHering,Eueides libitinaStaudinger,Heliconius xanthocles explicataStichel,H. eleuchia(Hewitson) andH. leucadiaBates together with a supplementary revision of the tribe giving information published since 1972. The following new forms are described:Eueides emsleyisp. n. and nine new subspecies ofHeliconius: H. aoede philipi, H. wallacei araguaia, H. pardalinus orteguaza, H.p. butleri, H. hecale australis, H.h. barcanti, H. clysonymus tabaconas, H. congener aquilionaris, H. sapho candidus.Geographical details of the refugia are given in Appendix I, and in Appendix II the heliconians are assigned to the postulated refugia.