In volume IV of Herbarium Pedemontanum, Luigi Colla cited 27 species based on Brazilian specimens distributed by Carl Martius in 1827. Of them, 22 were treated as new species. The original material examined by Colla (now held at TO) was found and compared with duplicates held elsewhere. Material was located for all but six of the taxa described by Colla. Fifteen hitherto unresolved species names are here clarified, along with fourteen new synonymies, and twelve proposed lectotypifications. Based on the collecting localities and comparison with specimens at Herbarium Martii at BR and elsewhere, at least 17 of the specimens distributed by Martius could be attributed to Prince Maximilian zu Wied.