Human beings are themselves organic micro-ecosystems integrated into the macro-ecosystem of nature, from which they draw what they need for their subsistence and health security. The great medical practices of Egypt, Mesopotamia, ancient Greece and the Roman Empire bear eloquent testimony to this. This work on the medicinal virtues of plants is in three parts: a phytomedical study of ten plants, a morphological and botanical study of the plants and the outline of a phytomedical lexicon. The plant names are in Latin, modern languages, Creole and African and Asian languages.