(1519-1603) Physician, philosopher, and botanist, born Arezzo, Italy; died Rome, Italy. He was educated at the University of Pisa where he later taught philoaophy, medicine, and botany; directed the botanical gardens at Pisa, 1554-1558; and was professor of medicine at Sapienza, and physician to Pope Clement VIII. As a philosopher he adhered to the doctrines of Aristotle, excluding any contrary to Revelation. He made important investigations concerning the circulation of the blood but is most famous for his botanical work "De Plantis Libri XVI" which contains the foundations of plant morphology and physiology. He made one of the first herbariums, and was the author of a mineralogical work. The plant species Cesalpinia is named in his honor.