Reduction of Gagnepain’s genera Cryptanthela, Dimerodiscus, and Tridynamia (Concolvulaceae)

In Notulae Systematicae 14, fasc. 1 (1950) 24—27, Gagnepain published three new genera of Convolvulaceae, viz. Cryptanthela (l.c. p. 24), Dimerodiscus (l.c. p. 25), and Tridynamia (l.c. p. 26), each of them based on a single species. These species are respectively Cryptanthela sericea Gagnep., Dimerodiscus fallax Gagnep., and Tridynamia eberhardtii Gagnep., all found in Indo-China. The types are preserved in the Paris Herbarium. Through the kindness of the Director of the Phanerogamic division of the “Museum National d’Histoire Naturelle” in Paris, I had the opportunity to study the types, with the following result.