In the course of studying all surviving copies of Arabic Dioscorides manuscripts I have come across some interesting statements in the introduction and colophon of a Leiden manuscript of De Materia Medica. This manuscript belongs to the Warner Collection or Legatum Warnerium of the Library of the University of Leiden, Cod. Or. 289. This vast and valuable collection of oriental manuscripts was acquired by Levinus Warner in the early seventeenth century during his term of appointment as Dutch ambassador to the Ottoman court in Istanbul. The collection was given to the university upon the death of Mr. Warner in 1665.