Aristotle's De Animalibus has been a very important source of zoological knowledge both for the ancient Greeks and for the medieval Arabs and Europeans. The work has twice been translated into Latin, once direct from the Greek by William of Moerbeke and once by Michael Scot from an existing Arabic translation. Of these, Scot's translation is the oldest. The De Animalibus is composed of three sections: 'History of Animals' (10 books), 'Parts of Animals' (4 books) and 'Generation of Animals' (5 books). The present volume contains the first critical edition of Scot's translation of the second section. The edition of the third section is already available (1992), the first section is in preparation.