innervates lamina medulla optic chiasma first optic chiasma fly_anatomy.ontology Chiasma lying between the lamina and medulla of the optic lobe (Ito et al., 2014). Axons reverse the anterior-posterior order between the lamina and the medulla, with axons from the anterior lamina cartridges projecting to the posterior medulla columns (Ito et al., 2014). VFB:FBbt_00005810 OCH1 outer optic chiasm FBbt:00005810 first optic chiasm