Developed from the "Schools of Liberal Arts" which flourished at Bologna in the 11th century. It was a "jurist" university in origin, owing to the organization by Imerius of a school of law, distinct from the arts school in the early 12th century and the adoption of the "Decretum Gratiani" of the Camaldolese (or Benedictine) monk, Gratian, as the recognized text-book of canon law (c.1140). The work was continued by such eminent jurists as Odopedus (died 1300), Joannes Andrea (1270-1348), Saint Raymond of Pennafort (1175-1275), and Ricardus Anglicus (c.1250). At the beginning of the 13th century the university is said to have numbered 10,000 students, the foreigners forming two "universities," the Cismontanes comprising 17 nations and the Ultramontanes 18 nations, organized like guilds. It was a "student university," the professors being hired by the students, with two kinds of lectures, an "ordinary" lecture reserved for the doctors and an "extraordinary" one which might be given by a student as part of the preparation for his baccalaureate degree. No examination was required for the bachelor's degree, a private one was necessary for a Licentiate and a public one for a Doctorate. Permission to lecture was given after five years study of law. The medical school was organized by Thaddeus of Florence, c.1260,and the foundations of modern anatomy were laid by Mundinus (1275-1326). The faculty of theology was established by Pope Innocent VI, 1360, and received many privileges from succeeding popes. Numerous colleges were established by laymen and ecclesiastics, all being finally consolidated into one university. Modern literature and science owe much to this university and classical studies flourished there under such great humanists as Francesco Filelfo (1398-1481) and in more recent times Giuseppe Mezzofanti (1774-1849), later a cardinal. Among the distinguished men of natural science, the university counts the anatomists Alessandro Achillini (1463-1512), Andreas Vesalius (1514-1564), and Marcello Malpighi (1628-1694); the botanist, Ulisse Aldrovandi (1522-1607); and the physicist, Luigi Galvani (1737-1798). Among the famous women professors were the mathematicians, Laura Bassi (1711-1778) and Maria Agnesi (1718-1799), and the Greek professor, Clotilda Tambroni (1758-1817). The university suffered during the Napoleonic wars but was greatly assisted by the popes until the suppression of the Papal States. Its library was founded by Aldrovandi in 1605 and numbers about 250,000 volumes. Included in the university are faculties of philosophy and letters, mathematics, science, law, medicine, and schools of pharmacy, agriculture, and engineering.