The Physiologus is a didactic Christian text written or compiled in Greek by an unknown author, in Alexandria; its composition has been traditionally dated to the 2nd century AD by readers who saw parallels with writings of Clement of Alexandria, who is asserted to have known the text, though Alan Scott has made a case for a date at the end of the 3rd or in the 4th century. The Physiologus consists of descriptions of animals, birds, and fantastic creatures, sometimes stones and plants, provided with moral content. Each animal is described, and an anecdote follows, from which the moral and symbolic qualities of the animal are derived. Manuscripts are often, but not always, given illustrations, often lavish.