Franciscus called Sylvius, was a descendant of a protestant family named Du Bois (changed to de le Boë¹) from Cambrai, in France. For religious reasons the family moved to Germany. Sylvius was born in Hanau, Germany. He read medicine at the universities of Sedan and Leiden. He began his studies in June, 1632 at Leiden and offered a disputation Positiones variae medicae in 1634. Sylvius obtained his medical doctorate at the University of Basel on 16 March 1637, defending a thesisDe animali motu ejusque laesionibus. According to Haller this is the first description of the lateral cerebral fissure. This fissure and the cerebral aqueduct were not fully described by Sylvius until 1663.1

He practised for a short period but graduated again at Leiden University in November 1638. His skills in teaching anatomy brought him respect and a certain fame: “many students, and certainly not the worst ones, attended his courses, so that it seemed as if only he could understand and explain anatomy.”

One of these students was Thoma Bartholini, son of the famous Danish anatomist Caspar Bartholini. In the 1641 edition of his well known textbook Institutiones anatomicae published by Thoma, 12 years after Caspar's death, it is clear that Caspar with Sylvius had shown and named the cerebral fissure separating …