3H-thymidine injections from E18 to E19 and survival to postnatal day (P)5 (posterior coronal)
Figure 73. This slice through the olfactory peduncle includes the main olfactory bulb (MOB) medially, the accessory olfactory bulb (AOB) dorsally, and the anterior olfactory nucleus (AON) laterally. The AOB output neurons were all generated before the morning of E18 ; the granule cells are heavily labeled; small cells throughout the rest of its layers are nearly all labeled. Labeling patterns in the MOB are nearly identical to the patterns in the more anterior slice in Figure 72. Many labeled young neurons and neuronal precursor cells in the rostral migratory stream are migrating into the MOB granular layer and periglomerular layers (arrows). Most of the tiny cells in the rostral migratory stream are going to the anterior MOB. Some pars externa and superficial cells in the AON pars lateralis are unlabeled on the morning of E18, but deep cells in the pars lateralis are heavily labeled.