562 'Journal of Comparative Neurology and Psychology. 



EXPLANATION OF PLATE V. 



Figs. 2 to 10. Cross-sections of the left half of the head at different levels. The outlines were 

 drawn with a camera lucida; the details are schematic. These were made from a different series of 

 sections than that from which fig. i was plotted. After the description of each figure is given the num- 

 ber of the section in fig. i which corresponds approximately to the section described. 



Fig. 2. Cross-section through the nasal capsule at the level where the branch of the olfactory nerve 

 that innervates Jacobson's organ is passing around to the dorsal side of the latter structure. Section 

 2CX). X 30. 



Fig. 3. Cross-section through the nasal capsule at the point where the olfactory ner\e trunk 

 breaks up into its terminal divisions and enters the capsule. Section 260. X 30. 



Fig. 4. Cross-section cutting through the posterior portion of the eyeball. To show the retractor 

 and levator bulbi muscles and their insertion on the antorbital cartilage. Section 350. X 20. 



Fig. 5. Cross-section at the level where the r. mandibularis V enters the lower jaw. Section 

 460. X 20. 



Fig. 6. Cross-section through the origin of the r. mandibularis V. The abducens ners^e is seen 

 separating from the gasserian ganglion. Section 560. X 30. 



Fig. 7. Composite cross-section through the roots of the VII and VIII ners'es. Sections 675- 

 680. X 30. 



Fig. 8. Cross-section through the roots of the lateral line component of the VII nerve. Section 

 685. X 30. 



Fig. 9. Cross-section slightly posterior to that of fig. 8. X 20. 



Fig. <)a. An enlargement of a part of the preceding, showing the r. communicans. 



Fig. 10. Cross-section at the level where the roots of the lateral line components of the X nerve 

 enter the brain. Section 710. X 30. 



