PLATE 4 



EXPLANATION OF FIGURES 



9 Cross-section through the head just behind the orbital region to show the 

 bony structure of the side and base of the cranium. The section is oblique 

 with their left side in advance; on the left side, the section passes through the 

 ganglionic fossa, on the right through the lateral recess (Pomolobus pseudo- 

 harengus). 



10 Cross-section through the head at the articulation between the prootic 

 and basioccipital bones. On the left side the section passes through the front 

 part of the posterior osseous capsule, on the right side, just in advance of that 

 ■structure (Pomolobus pseudoharengus). 



