Adriaan van de Spiegel (Adrianus Spigelius), who came from a family of surgeons, studied at Louvain, Leiden and later under Fabricius and Casseri at Padua, from where he received his M.D., and where for a time he occupied the Chair of Anatomy and Surgery. The original text of his anatomy was not illustrated, and together with his treatise on the development of the fetus, remained unpublished during his lifetime. In his will he requested Daniel Bucretius (Rindfleisch) to publish both. Bucretius duly obliged, and illustrated the text with plates acquired from Casseri's heirs, which Casseri had been preparing for an unpublished anatomical work, unfinished at the time of his death in 1616. Of the original seventy-eight plates, one was destroyed, a further twenty plates by the same artists and engravers who had produced Casseri's original plates were added. Giulio Casseri (1552-1616) received training in anatomy at Padua under Fabricius. He produced many anatomical illustrations, some of which were published during his lifetime, others were included in posthumous works, sometimes under his name, sometimes with others names attached. He intended to produce a fully-illustrated anatomy of the whole body, but did not live to complete it. Seventy-seven of Casseri's plates were acquired by Bucretius to illustrate Spiegel's texts. The plates were drawn by Odoardo Fialetti, a pupil of Tintoretto, and engraved by Francesco Valesio.