Fig. 5.

Images of cases Q24 and Q303. Both chimeric brains were sectioned in a plane orthogonal to the peduncle. Q24 was only processed for QCPN IMR, and Q303 was processed for Tbr1 ISH and QCPN IMR. a Drawing of Q24 graft extent relative to the prosencephalic fate map. b Schema of the Q24 chimeric brain, illustrating the plane of the sections shown in (c–d). c The section is perpendicular to the peduncle (pe), thus coinciding roughly with the direction of the eminential migration streams; alar hypothalamic level. c’ Higher magnification of c showing the quail-labelled juxtapeduncular stream (black arrowheads). d More dorsal section passing through the di-telencephalic transition. d’ Higher magnification of d showing the quail-labelled elements in the juxtapeduncular and peripeduncular streams (black and red arrowheads, respectively). e Drawing of Q303 graft extent relative to the prosencephalic fate map. e’ Schema of the Q303 chimeric brain, illustrating the plane of the sections shown in (f–l). f–i Ventrodorsal series through the PThE showing its neighborhood relationships with the PTh, Pa and PallA. g–i’’ Higher magnification of g–i showing details of the peripeduncular, juxtapeduncular and eminentio-septal streams. j–l Three consecutive sections through the subpallium at the level of the commissural septum. Blue arrowheads indicate the ventricular borders of the graft. Red arrowheads point to the peripeduncular stream. Black arrowheads point to the juxtapeduncular stream. Green arrowheads point to the eminentio-septal stream. Scale bars in a and e, 250 μm, b and e’, 2.5 mm, c and d, 150 μm, c’ and d’, 50 μm, f–i, 150 μm, g’–i’’, 50 μm, j–l, 150 μm