114 EQUINE ANATOMY. 



fasciculus of the bulb, by eight or ten roots, uniting to 

 forjn the petrous ganglion. Course : Downwards with 

 a curve concave forward, behind the great branch of 

 the hyoid bone, between the guttural pouches and mas- 

 seter muscle, runs alongside the hyoid bone and reaches 

 the base of the tongue, where it terminates. Collateral 

 branches : 1 — The nerve of Jacobson, giving off the 

 great and small deep petrosal ; 2 — Branches to the 

 superior cervical ganglion ; 3 — Branch to the cartiod 

 plexus ; 4 — a pharyngeal nerve to the superior wall 

 of the pharynx. 



10. — Fneumogastric or par vagum. — Origin: Two 

 roots: the sensitive from the grey mass near the floor 

 of the fourth ventricle behind the glosso-pharyngeal, 

 then passes out of the cranium to the jugular ganglion ; 

 the motor root rises more posteriorly from the middle 

 of the respiratory track, runs also outwards and goes 

 to the jugular ganglion, which is elongated, flattened 

 from above below and imbedded in the cartilaginous 

 mass closing the foramen lacerum. Course : After its 

 ■connection with the ganglion, the mass is united to the 

 spinal, but soon separates from it, leaves the glosso- 

 pharyngeal pass between them alongside and behind 

 the guttural pouches, crosses the occipital artery, unites 

 with the cervical portion of tlie great sympathetic, 

 passes into tlie tliorax, and then separates from this 



