Schematic drawings of frontal sections through the embryonic mouse telencephalon (at E12.5 or E14.5), representing the major histogenetic subdivisions of the subpallium. LGE produces the striatal components of the telencephalon. MGE is the pallidum proper and produces the globus pallidus. AEP is related to the peduncle/internal capsule, and produces many sublenticular components of the extended amygdala. POC is related to the anterior commissure, shows specific expression of Shh in the ventricular zone, and produces the cholinergic cells of the basal telencephalon and the dorsolateral preoptic region. The septum also contains striatal- and pallidal-like subdivisions. Note that AEP and POC extend into the posterior medial amygdala and into the septum. See text for more details. For abbreviations, see list.