410 



PHYSIOLOGY 



CHAP. 



nerve. Bellinger! gave the name of masticator nerve to the 

 motor root because it is distributed to the masseter, temporal, and 

 the two pterygoid muscles, but it also gives branches to the 

 mylo-hyoid, the anterior belly of the digastric, tensor palati, and 

 the tensor tympani. 



Charles Bell (1821) first affirmed that the gaugliated root, 

 the 5th nerve, was the sensory nerve of the face, but it was 

 Fodera (1823) who first performed intracranial section of the 



FIG. 217. Diagram of brandies of fifth pair. (After a sketch by Charles Bell.) J. 1, Small root 

 of 5th nerve ; -2, large root, passing forwards into the semilunar ganglion ; 3, placed on the 

 bone above the ophthalmic nerve, which is dividing into the. frontal, lachrymal, and naso- 

 ciliary brandies, the latter connected with the ciliary ganglion ; 4, placed on the bone close to 

 foramen rotundum, marks the maxillary division, which is connected below with the splieno- 

 palatine ganglion, and passes forwards to the infra-orbital foramen ; 5, placed on the bone over 

 the foramen ovale, marks the mandibular nerve, giving off aurieulo-temporal and muscular 

 branches, and continued by inferior dental to lower jaw, and by lingual to tongue ; a, sub- 

 maxillary gland, with sub-maxillary ganglion placed above it in connection with lingual nerve ; 

 6, chorda tympani ; 7, facial nerve, issuing from stylo-mastoid foramen. 



trigeminal on rabbits, and saw that sensibility was abolished in 

 all the external parts of the face, and on the mucous membrane 

 of the nose, cheeks, and tongue. Fodera's observations were con- 

 firmed and amplified by H. Mayo, Magendie, Eschricht, and 

 others. 



Unilateral paralysis of the motor root of the trigeminus 

 paralyses the masticator muscles of the same side, so that in 

 mastication the jaw is pulled towards the paralysed side and the 

 teeth of the upper and lower jaws no longer meet accurately. 



