The pharmacopeia of Pedanius Dioscorides (20-70 ce), entitled Peri Ylis Ialikis (latinized as De Materia Medica, On Medical Matters)was written in Greek about the year 65. It was destined to be one of the most famous books on pharmacology and medicine but is also richin horticulture and plant ecology. An illustrated alphabetical version of Dioscorides’ manuscript was completed in Constantinople about 512. This magnificent volume was prepared and presented to the imperial Princess Juliana Anicia (462-527), daughter of the Emperor Anicius Olybrius, Emperor of the Western Roman Empire. The bound manuscript stored in Ōsterreichische National bibliothek in Vienna is available in facsimile and is now referred to as the Juliana Anicia Codex (JAC) or the Codex Vindobonensis Dioscorides. The JAC contains 383 paintings of plants including many horticultural crops, many of which can still be recognized in modern day examples. Ananalys is of the illustrations indicates that they were made by numerous artists of varying skills and it is probable that some were derived from an earlier lost version. The Codex Neapolitanus (NAP) (late 6th or early 7th century) which now contains 406 plant images on 172folios resides in the Biblioteca Nazionale, Naples is closely related to JAC, and is also available in facsimile editions. A comparison ofthe 352 common illustrations contained in both NAP and JAC suggests that many of the illustrations derived from a common source,perhaps an illustrated collection owned by Theodosius II, but the possibility also exists that some of the NAP images are direct copies of JAC images. There are 31 images in JAC which do not appear in NAP, 1 is a 13th century addition, 4 are images that can be assigned to2 torn pages. and 26 can be assigned to 11 missing leaves of the NAP. Of the 54 images in NAP which do not appear in JAC, 2 are likely to have been Mandragora included in lost folios in JAC, but the other 52 may include other images that existed in the common source. While common images in NAP and JAC are often very similar, 11.6% show substantially differences including variants of the same plant in different stages. Additional images in the archetypic source including different stages of the same plant could have provided the copyists working on JAC and NAP the opportunity to select different images to fulfill their commissions.
