Click on image to view larger version.
FIG 1. The coronal section through the telencephalon of 18-week-old human fetus, Gallyas silver staining. Note that fiber bundles and their crossings are located in the fetal "white matter"—ie, in periventricular region (C1, C2, and asterisks)—and the intermediate zone (iz), whereas the subplate zone (sp) is characterized by a loose ("isotropic") argirophilic network of fibers. The fetal "white matter" consists of tangentially stratified fiber bundles such as external capsule (arrowheads), corpus callosum radiation (cc), thalamocortical projection fibers (arrow), and the deep system (double arrows; see insert C1). In addition, a prominent periventricular system of unstained and transversely or obliquely cut fiber bundles (row of asterisks) is situated in the subventricular zone. Abbreviations for this and subsequent figures: a = amygdala; ac = anterior commissure; bf = basal forebrain; c = caudate nucleus; C1 –C6 = crossroad areas; cc = corpus callosum; ge = ganglionic eminence; gp = globus pallidus; ic = internal capsule; iz = intermediate zone; p = putamen; sp = subplate zone; th = thalamus.
