From 750 A. D. on, medical studies expanded quickly in the Muslim world. Because of this, many new forms of writing up the information, flowing from all parts of the world, was necessary. One kind of textual model which has not been studied previously is that which concentrates on giving the physician substitutes (abdal) for the most commonly used materia medica. To bring this to the attention of students of medieval medical history, this present work contains the texts and translations of three of the oldest treatises extant on the subject in Arabic. Since one of the works is by Masarjawaih, of about 710, it may be shown by their comparison that the Arabic vocabulary of plant names was already well established at that time. Botanonymic study has proved that the botanicals and minerasl mentioned had been transmitted to the Muslims largely from the Indians, Persians, Greeks and other sources in Mesopotamia.