Caudal Perspective of Olfactory Nerve. The olfactory nerve is divided in the olfactory bulb (1), olfactory tract (2), olfactory trigone (3) and medial (4) and a lateral (5) olfactory stria in front of the anterior perforated substance (6) in a frontal lobe basal view. The orbital surface is lateral to the olfactory tract; it is divided in the anterior orbital gyri (7), the medial orbital gyri (8), the posterior orbital gyrus (9), and lateral orbital gyri (10). (Image courtesy of E de Oliveira)