O' Grady in the BM Catalogue states that the article on the hare (Chapter 170, Lepus) is based on the Book of Simple Medicines of Ibn Sarabi, otherwise Serapion the Younger. It will be necessary to check Serapion's book as a possible source for some of the Irish text. Very little is known of Serapion except that he lived probably in the 12th century, and that he was a physician who wrote in Arabic and who may