F, Another specimen in which the anterior portion of the hemisphere has been removed to expose the temporal horn. The M1, M2, and M3 and the P2A, P2P, P3, and P4 have been exposed. The branches of the PCA pass back to the occipital pole. G, Enlarged view. The anterior segment of the uncus faces the carotid, middle cerebral, anterior choroidal, and posterior communicating arteries. The posterior segment of the uncus, which forms the lateral margin of the crural cistern, faces the P2A, the basal terminal part of the AChA and the uncal apex is located lateral to the oculomotor nerve. The basal vein courses above the PCA. G, Enlarged view. The anterior segment of the uncus faces the carotid, middle cerebral, anterior choroidal, and posterior communicating arteries. The posterior segment of the uncus, which forms the lateral margin of the crural cistern, faces the P2A, the basal terminal part of the AChA and the uncal apex is located lateral to the oculomotor nerve. The basal vein courses above the PCA. H, Upper surface of the temporal and occipital lobes. The M1 courses along the stem of the sylvian fissure below the anterior perforated substance. The M2 begins at the limen insula and courses over the surface of the insula. The M3 courses over the opercular lips. The M4 is distributed to the cortical surface. The P2 has been preserved. It courses medial to the posterior segment of the uncus and para-hippocampal gyrus and through the crural and ambient cisterns. The calcarine branch courses deep in the calcarine sulcus on the medial side of the atrium. I, Inferior surface of the temporal lobe. The P2 branches are distributed to the inferior and the lower part of the lateral surfaces of the temporal and occipital lobes. The M1 courses above the anterior uncal segment. (Images courtesy of AL Rhoton, Jr.)