Median protocerebrum and central complex. (A) Overview of the brain from posterior. A large 5HTir PCC connects both hemispheric lPC ventrally to the CB. (B) The central complex labeled against RF-amides showing the anterodorsal cluster 6, the PB, CB and lal, frontal section. The CB is ensheathed by a couple of somata, none of which showing RFir (compare with F). The PB is interconnected by a commissure (dotted circle). (C) Ventral extensions of (6) and (8), CB and lal. A couple of somata are distributed around the CB. The bipartite lal are interconnected by two large commissures (solid circles), horizontal paraffin section. (D) Frontal section of CB. 5HTir of commissures interconnecting the lal (solid circles). The CB is also innervated by neurons (dotted circle, Z) from (6), corresponding to tract Z [according to Utting et al. (2000); dotted circle, see E′]
(E) Anterolateral region of the mPC showing the anterior unit of the lal, also a small part of the PNT is visible (dotted circle), frontal section. The CB (posterior to this section plane) is indicated by a dotted line. (E′) Single channel image showing TUBir of projections of cluster 6 corresponding to tract W, X, Y and Z, innervating the CB and lal. (F) Frontal section of CB. 5HTir of PB commissure (dotted circle) and arborizations of neurons from (8) (arrowhead) bypassing the CB ventrally (solid circles).