850 



THE NERVES. 



Comparison of the Cbanial Nebves of Man with those of Animals. 



The few modifications offered by the cranial nerves of Man, when compared with those of 

 animals, are dictated by the disposition of tlie parts and organs to wljich they are distributed. 



"We li;ive spoken of the ul/actory lobes when studying the brain, bO that we need not again 

 refer to tliem. Tlie three succee-ling nerves olfer nothing wortliy of mention. 



Trigeminal nerve. — This has the same origin and divisions as in animals. 



The frontal nerve of the oplithiilmic portion divides into two branches ; these are inflected 

 upwarils on tlie margin of the orbit, and distributed to tlie skin of ihe forehend. These two 

 branches — well developed in the Dog — are distinguished as internal and external. The latter 

 anastomoses with a branch of the facial. The nasal nerve, after spreading over the surface of 

 the turbinated bones and tlie meatus, gives ofl" u ramuscule that becomes subcutaneous in 



Fig. 462. 



NERVES OF THE FACE AND SCALP. 



1, Attrahens aurem muscle; 2, anterior belly of occipito-frontalis; 3, auriculo-temporal nerve 5 

 4, temporal branches of facial; 5, attolens aurem muscle; 6, supra-trochlear (5th); 7, posterior 

 belly of occipito-frontalis ; 8, supra-orbital ; 9, retrahens aurem muscle; 10, temporal branch of 

 temporo-orbital ; 11, small occipital; 12, malar branches of facial ; 13, posterior auricular (7th) ; 

 14, malar branch of temporo-malar (5) ; 15, great occijiital ; 16. infra-orbital branches of facial ; 

 17, facial ; 18, nasal; 19, cervico-fatial division of 7th ; 2' >, infra-orbital ; 21, branches of digastric 

 and stylo-hyoid ; 22, temporo-fncial division of 7th ; 23, great auricular; 24, buccal branches of 

 facial; 25, trapezius muscle ; 26, buccinator (.')th) ; 27, splenius capitis ; 28, niasseter ; 29, sterno- 

 mastoideus ; 30, superma.xillary br;inches of facial nerve ; 31, superficial cervical ; 32, mental ; 

 33, platysma muscle ; 34, submaxillary brnnches of facial nerve. 



passing between the inferior border of the nasal bone and cartilage of the nostril ; this is the 

 naso-lobular nerve. 



The siiptrior ma:eiUary nerve leaves the cranium by the foramen rutundura. n aches the 

 suborbital furrow, an<l sjireads over the fnce by snboibital branches. Like th.'t of animals, it 

 gives rise to an orbital ramuscule, and posterior und anterior dental branches. Differences 

 appear in the otlier branches whicii are furnislied. in animals, by the superior maxillary nerve: 

 in Man these branches leave Meckel's ganglion. 'I'lie lilann nts leaving this ganglion are: 

 1. The pharyngeal nerve of Bock, which is distributed in the upper portion of tiie mucous 

 membrane of the pharynx, in that of the Eustachian tube, and the posterior orifice of the 

 nasal cavities. 2. The palatine nerves — great or an/erior— sent to the mucous membrane of 



