2i8 Journal of Comparative Neurology. 



The posterior division of the laterahs VII root, immediately- 

 after its exit, comes in contact with the fibers of the dorsal VIII 

 root as they enter the brain. Having passed cephalad of the 

 latter root it immediately comes in contact with the dorsal side 

 of the communis VII root, as the most anterior fibers of the 

 latter emerge from the brain and while the lateral margin of the 

 lateralis root is still in contact with the dorsal VIII root. For 

 a short distance beyond this point the lateralis root becomes 

 separated from the communis VII and dorsal VIII roots, but 

 when the latter has turned laterad into the ear capsule the later- 

 alis root assumes like relations with the ventral VIII root and 

 the communis VII root. 



As the two divisions of the lateralis root separate from each 

 other, the posterior division comes in contact for the first time 

 with the motor root of the facialis which at this level has come 

 to lie laterally of the communis root. The three roots then 

 turn laterad together into the foramen of the facialis, which 

 penetrates the antero-ventral portion of the ear-capsule. At the 

 distal opening of this foramen the lateralis component enters its 

 ganglion from which arise the axones of the r. mentalis VII. 



^. — TJie Auditory and Communis Roots. 



From the area which is between the exits of the lateralis- 

 and motor VII roots, three roots arise; the dorsal and ventral 

 VIII, and the communis VII. The two larger and posterior 

 sections of this area belong to the auditory roots. The section 

 belonging to the dorsal VIII projects slightly farther caudad 

 than that of the ventral VIII. The contiguous margins of these 

 two sections diverge anteriory and the section belonging to the 

 communis VII is wedged in between them. It extends, also, 

 dorsad anteriorly of the dorsal VIII section, and it lies dorsally 

 of the anterior portion of the ventral VIII section. 



The dorsal auditory root projects laterad and a little 

 cephalad into its ganglion. The ventral VIII inclines cephalad 

 ventrally of the communis VII, dorsally of the motor VII and 

 mesially of the dorsal VIII root. It at length passes around 

 the anterior margin of the ganglion of the dorsal auditory root 



