342 Journal of Comparative Neurology. 



orbital, not drawn on the plot) separates, which passes 

 back along one of the large tendons of the m. adductor 

 mandibulas. Its ultimate distribution could not be deter- 

 mined. It may represent a nerve for muscular or tendon 

 sensation. 



Having now reached the cephalic end of the quadrate, 

 the r. mandibularis V now turns inward and takes its 

 position on the inner face of the articular bone a short 

 distance dorsad of the r. mandibularis VII. It lies imme- 

 diately dorsally of Meckel's cartilage, while the mandibu- 

 laris VII lies ventrally of it, and this position it maintains 

 nearly to the tip of the mandible. Here it gives off a 

 minute coarse-fibred twig {io. i6) to a separate slip of 

 the m. adductor mandibulae which lies mesally of the 

 articular and dentary. 



Having reached the cephalic tip of the articular bone 

 (i6o), there separates from the r. mandibularis V the 17th 

 infra-orbital, which is the second anastomosing branch for 

 the r. mandibularis VII {V-VII. 2). This branch con- 

 tains nearly all of the remaining coarse fibres and some of 

 the fine and medium ones. It descends between Meckel's 

 cartilage and the extreme tip of the articular bone to join 

 the r. mandibularis VII and then distributes to the mm. 

 genio-hyoideus and intermandibularis and the skin of the 

 ventral surface of the mandible and lower lip, as already 

 described. 



Farther forward the remainder of the r. mandibularis 

 V enters a canal between the dentary bone and Meckel's 

 cartilage and finally emerges through a foramen to the 

 ectal aspect of the dentary bone. As it is passing through 

 its foramen it gives off a small branch (75) and this is fol- 

 lowed by numerous similar branches which supply the 

 skin of the side of the mandible both cephalad and caudad 



