MUSTKLUS LJ]VIS. 163 



Addj3, but that muscle here separates into two heads, oue of 

 which has its origin from the mesial edge of the ventral 

 opening of the cartilaginous nasal capsule, near its hind 

 end, while the other arises, dorsal to the hind end of the 

 nasal capsule, from the dorsal and ventral surfaces of the 

 projecting veutro-lateral end of the antorbital process. 



Anterior to this point the truncns follows the ventral head 

 of the muscle Add/3, lying- ventral to its antero-lateral edge, 

 and, with it, crossing the hind end of the ventral opening 

 of the cartilaginous nasal capsule, posterior to the external 

 nasal aperture. Anterior to the muscle Add/3, what is left 

 of each of the two main nerves turns directly forward, and 

 here lies near the lateral edge of the horizontal plate-like 

 extension of the ventral edge of the internasal cartilage. 

 In this position the two nerves pass mesial to the external 

 nasal aperture, and, anterior to that aperture, lie at first 

 along the ventro-mesial aspect of the rounded anterior end 

 of the nasal capsule, in the angle between the capsule and 

 the ventro-median rostral bar of cartihige, and then, anterior 

 to the capsule, continue forward toward the end of the snout, 

 remaining always along the lateral aspect of the ventro- 

 median rostral bar. 



The general course of this trunciis buccalis-maxillo-man- 

 dibularis having now been described, the branches of the 

 three nerves that form it can be given. 



Ramus Buccalis Facialis. 



The first five branches of the buccalis facialis arise from 

 the ganglion of the nerve, and not from the nerve itself. 

 The first three branches are given off, close together, from 

 a dorso-posterior prolongation of the ganglion of the nerve, 

 and have already been fully described when describing the 

 lateral organs they innervate. They run upward and back- 

 ward in the orbit, along the side wall of the skull, and 

 separate into four branches, one of which pierces the over- 

 hanging orbital roof to innervate organs 103 to 110 infra- 

 orbital, while the other three turn outward and innervate 



