Historiae animalium ("History of the Animals") published at Zurich in 1551–58 and 1587, is an encyclopedic work of "an inventory of renaissance zoology" by Conrad Gessner, a medical doctor and professor at the Carolinum in Zürich, the precursor of the University of Zurich. It is the first modern zoological work that attempts to describe all the animals known, and the first bibliography of natural history writings. The five volumes of natural history of animals cover more than 4500 pages.