Figure 2. Octopus nervous-system anatomy. (a). Octopuses are highly mobile predators with nearly 40 central brain lobes (light blue). (b). Dorsal view of the central brain of Octopus bimaculoides. Two large optic lobes (OL) flank the supra- and subesophageal masses. The oral direction is toward the bottom of the panel. VL: vertical lobe; FL: frontal lobe; OG: optic gland. (c). Coronal view of the central brain and optic lobes of Octopus bimaculoides, H&E-stained section. Each of the 5 vertical lobules encloses a tube of neuropil (bracket). Eso: esophagus; Sub: subesophageal mass.