lEpibranchial placodes: pharyngeal
endoderm (BMP-7 signal), Pax2 and Sox3
lOphthalmic placode of V: neurectoderm of
mesencephalon (diffusible signal ?), Pax3
lOtic placode: initially axial and
non-axial mesoderm, Pax 8; later hindbrain (FGF-3,-8,-10 signals), Pax2, Sox3, Notch
lLens placode: forebrain & anterior
mesoderm (BMP-4, later BMP-7 signals), Pax6, later Pax2
lOlfactory placode: anterior mesoderm
(and forebrain? – no signal identified as yet), Pax6