In the French botanist Henri Baillon publication "Étude générale du groupe des Euphorbiacées" (1858), a large morphological description of genus is made, and a peculiar classification is presented: two sections are considered –“"Sect. A"” and “"Sect. B"”– depending on whether the inflorescence axis is simple or branched out, and the female flowers calyx consists of three or five sepals. Baillon continued to publish a series of works under the title "Euphorbiacées américaines", to be issued in the first volumes of Adansonia journal, between 1860 and 1864. More than fifty new species of "Acalypha" are described thereto, most of them from South America, and specially from Brazil.