THE HEAD AND NECK, POSTERIOR. 151 



branches on the face are four labial (usually), three or 

 four nasal, and two small palpebral branches, supplying 

 in turn the upper lip, side of the nose, and the lower eye- 

 lid. 



The communications of these branches with the infra- 

 orbital branch of the facial nerve forms the infra-orbital 

 plexus. See page 61. 



Meckel's, the Sphenopalatine, or the Nasal Ganglion. 

 Fig. ii. 



This is a small ganglion placed in the sphenomaxillary 

 fossa close to the sphenopalatine foramen and under the 

 superior maxillary nerve, to which it is suspended by two 

 sensory branches forming its sensory root. The motor and 

 sympathetic roots enter the posterior part of the ganglion as 

 the Vidian nerve. 



The Vidian nerve is formed by the junction of the great 

 superficial petrosal nerve from the facial with the great deep 

 petrosal branch from the sympathetic plexus on the carotid 

 artery in the carotid canal. The united nerves pass forward 

 through the Vidian canal to terminate in Meckel's ganglion. 

 Branches of the ganglion. 



(1) Ascending or orbital branches. Three or more very 

 small filaments which pass to the orbit through the spheno- 

 maxillary fissure and supply the periosteum and mucous 

 membrane of the posterior ethmoidal and sphenoidal 

 sinuses. 



(2) Descending branches. (a) The large or anterior 

 palatine nerve. Passes through the posterior palatine 

 canal to the roof of the mouth, which it supplies as far 

 forward as the incisor teeth. This nerve gives off two in- 

 ferior nasal filaments while in the posterior palatine canal, 

 which pass forward through minute openings to supply the 



