74 JOURNAL OF ENTOMOLOGY AND ZOOLOGY 



EXPLANATION OF FIGURES 



Figure 1. Nebalia from the side. The position of the ganglia is indicated in the draw- 

 ing. X12^. 



Figure 2. Longitudinal section of the central nervous system compiled from two 

 adjoining sections. Elements of all the centers are shown. The brain 

 is at the upper end. 



Figure 3. Longitudinal section through an optic lobe. X-15. 



Figure 4. Cross section of an optic lobe. X215. 



Figure 5. Cross section of the upper portion of the brain. X215. 



Figure 6. Cross section of the central portion of the brain showing centers of fibres. 

 X21S. 



Figures 7 and 8. Lower sections through the brain. X215. 



Figures 9-12. Cross sections through ventral regions of the nervous system. X21S. 



I 



