Olfactory Thalamic Equivalent. (A) Granular and progenitor cells form core of the olfactory bulb. Ventricular recess is within this core (22wk fetus). (B) Calretinin immunoreactivity in peri-glomerular neurons surrounding synaptic glomeruli (g) which are still non-reactive (19wk normal fetus). (C) A nodule of anterior olfactory nucleus within olfactory tract exhibits many synaptic vesicles (5-mo postnatal). Reproduced from Sarnat and Wu, 2016.