244 



THE CRANIAL NERVES. 



mentioned branch the mylo-hyoid muscle and the anterior belly of the digastric. 

 The branch to the internal pterygoid muscle, with which also are connected those 

 proceeding through the otic ganglion to the tensors of the palate and tympanum, is 

 sometimes counted as a part of the larger division, but is more correctly regarded 

 as arising from the undivided trunk. 



The short trunk of the nerve also gives off, as it issues from the foramen ovale, 

 a slender recurrent branch (n. spinosus), which passes backwards into the skull 

 through the foramen spinosum with the middle meningeal artery, and divides like 

 that vessel into two branches. The anterior of these sends its filaments into the 



Fig. 161. PLAN OF THE INFERIOR. MAXILLARY NERVE. (GK D. T.) 



great wing of the sphenoid bone, while the posterior traverses the petro-squamous 

 fissure, and is distributed to the mucous lining of the mastoid cells (Luschka). 



From the sheath which the inferior maxillary nerve receives from the dura mater in its 

 passage through the foramen ovale tubular prolongations are continued on the several offsets 

 of the trunk. Those containing the. masseteric and auriculo-temporal nerves are of consider- 

 able strength, and become blended with the capsule of the temporo-maxillary articulation in 

 front and on the inner side respectively, so that they are exposed to a certain degree of 

 traction during the movements of the lower jaw. (E. Fawcett, Journ. Anat., xxvii, 1893, 

 p. 179.) 



Varieties. One or more of the branches of the superior division of the nerve may arise 

 separately from the main trunk. 



There is not unfrequently a small fibrous band {pti>ry<jo-splu'noiclal ligam-f-nt') extending 

 from the root of the external pterygoid plate to a spot on the great wing of the sphenoid a 

 little in front of the foramen spinosum, and lying in the angle between the two divisions of 

 the inferior maxillary nerve. In rare cases this band is replaced by bone, so that the small 

 part of the nerve passes out through a special foramen on the under side of the great wing of 

 the sphenoid, just external to the foramen ovale. (Hyrtl," " Ueb. d. Porus crotaphitico- 

 buccinatorius," Wiener Sitzungsber., 1862 ; A. v. Brunn, " Das Foramen pterygo- spinosum 



