<prompt> All of the following canals open on the posteriorwall of the pterygo palatine fossa EXCEPTGreater palatine canalForamen RotundumPterygoid canalPalatovaginal canal  <response>: Pterygopalatine Fossa:This is a small pyramidal space situated deeply, below the apex of orbit.Communications:Anteriorly : With orbit through inferior orbital fissure.Posteriorly :With middle cranial fossa through foramen rotundum.With foramen lacerum through pterygoid canal.With pharynx through palatinovaginal canal.Medially : With nose through sphenopalatine foramen.Laterally : With infratemporal fossa through pterygomaxillary fissure.Inferiorly : With oral cavity through greater lesser palatine canals. 