Abu Ma’shar, an astronomer in 9th century Baghdad, was one of the most prolific writers on astrology during the Middle Ages. This work was cited by Albert the Great, Roger Bacon, Pierre d’Ailly, and Pico della Mirandola, among others. Stars appear on the constellation figures in an impressionistic manner, not as a sky map but rather as an aid to memory. This 1st edition was printed by Erhard Ratdolt, and the constellation figures appear similar to the ones in Ratdolt’s editions of Hyginus.