GESSORIACUM (anc. geog.), a port and station for ships of the Morini in Belgica. In Cæsar's time, according to Dio, there was no town; but Florus speaks of it as one; and the Gessoriacenses Muri are mentioned by Eusebius in his Panegyric. The author of Tabula Theolofiana, commonly called Prauniger's map, says expressly, that Gessoriacum was in his time called Bononia. Now Boulogne in Picardy. E. Long. 1. 30. N. Lat. 50. 40.