The complex of Fixcus Deltoidea ; A recent invasion of the sunda shelf

Abstract

A detailed account of the complex of F. deltoidea Jack and F. oleaefolia King is given in order that its problems may be taken up in the field. Thirteen varieties of F. deltoidea are distinguished, eight of F. oleaefolia . The link between them is F. deltoidea v. motleyana (Miq.) Corner. Clear evolutionary trends to very small figs and leaves and to dichotomous venation supply the evidence for the conclusions that the most reduced state F. deltoidea v. angustifolia (Miq.) Corner is the most widely spread; that the complex advanced into the lowland and mountain forests of the Sunda Shelf from Borneo; that the original connexion was with the ancestors of ser. Podosyceae Corner in the Philippines; that the large seed is a primitive retention; that the complex did not evolve through vicarious disruption of a widespread ancestor; and that, as a recent development of Ficus , possibly still in the making, it represents most clearly the manner of speciation and geographical distribution prevalent in the genus. New taxa: F. deltoidea Jack var. kinabaluensis (Stapf) Corner, F. oleaefolia King var. linearifolia Corner and var, valida Corner.