Fig. 2.

Ramón y Cajal (in 1891 for rodents and 1899–1902 for humans) was the first to describe neurons situated in the developing subcortical white mater of fetal and early postnatal mammals. However, Cajal regarded them simply as displaced from the adjacent cortex and called them white matter cells. (A) Golgi-stained neurons of supraventricular cortex of 1-month-old mouse: h, cells situated in the white matter (Ramón y Cajal, 1891a,b, p. 174;, plate II, fig. 7 – h, cellules siéegeant dans la substance blanche). (B) Rapid Golgi-staining of lateral entorhinal cortex (la corteza esfenoidal in Cajal's original) of 1-month-old human infant. (K–M) White matter cells with ascending axons (Ramón y Cajal, 1901, p. 50, Fig. 23: K–M, células de la substancia blanca provistas de axon ascendente; reproduced in German translation as Ramón y Cajal 1903, p. 61, Fig. 23: K–M, Zellen der weissen Substanz mit aufsteigendem Axencylinder; also reproduced in French translation as Ramón y Cajal, 1911, p. 696: K–M, cellules de la substance blanche munies d'un cylindre-axe ascendant).