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Fig. 8. Model of the steps involved in early OB morphogenesis. In the first step,
axons from the olfactory epithelium (OE) project to and make contact with the
anterior telencephalon (tel.). In a second step that is dependent on FGF
signaling, a reduction in the number of proliferating cells (dots) at the
anterior end of the telencephalon occurs (around the axons from the OE),
concurrent with an increase in the number of neurons (not shown). In the third
step, the decrease in cell proliferation causes initial bulb evagination
(purple).