Fig. 4

Sagittal histological section of the head of a Melissotarsus worker. This shows the extent of (a) dorsoposterior lobe and (b) ventral expansion. Arrow points at the zinc reinforcement on the mandible tip. Inset shows SEM of head with area of the histological section indicated in blue. Md, mandible; OcF, occiput foramen; SG, silk gland