martius and spix's trip through brazil during the 19th century gave rise to many works, including a latin manuscript by the famous botanist on the medicinal plants used in brazil. in 1843, martius published a list of over 800 species, classifying them according to the type of substance they contained. this important source of information on medicinal plants and historical ethnobotany was translated into portuguese by henrique velloso d'oliveira in 1854, aiming to make it more readily available to all readers. the translated version contains serious translation errors that cast doubt on species citations including the creation of new botanical names based on the original author's taxonomic comments, omission and addition of new usages, properties, modes of preparation, indications, comparisons, interpretation, and other botanical issues. several translation errors indicate a misunderstanding of taxonomic and morphological questions, further contributing to distortion of the original text. the translation alters the original text to such an extent that it should be disregarded in studies on medicinal plants in brazil. the original work, however, remains a rich source of information on this topic.