PROC. ENT. SOC. WASH., VOL. 20. 



PLATE 8. 



2 



.0 



IFM. 



MB 



EXPLANATION OF PLATE 



Fig. 1. Head of abnormal drone, side view. X 11. 



Fig. 2. Head of abnormal drone, face view. X 12. 



Fig. 3. Transverse section through head of abnormal drone passing 

 through the lateral ocelli, O. IFM, inner fibrillar mass; .!//>, mushroom 

 body; Aid, mandible; OE, oesophagus. X 21. 



Fig. 4. Transverse section through head of abnormal drone, slightly 

 caudad of that shown in figure 3. Lettering same :is ,-ibove. X 21. 



107 



