828 



THE NERVOUS SYSTEM 



and in passing downward form the spinal tract of the trigeminus, weU marked in aU transverse 

 sections of the medulla oblongata figs. 641, 642, 643, 649). The spinal tract decreases rfSv 

 m descendmg the medulla, owing to the rapid termination if its fibres^n tEucIeus oUheT^^^^^^ 



^'"'■.^.S'^^'^''''^^' Illustrating the Principal Central Connections of the Trigeminus 

 OR P^ImTda^^f'Lre™'' ^^"^^^^'^ °^ Their Relations to Descending CerebrL 



Internal, 

 capsule 



Hypothalamic 

 nucleus 



Mesencephalic 

 nucleus and 

 root of masti- 

 cator nerve 

 Medial lem- 

 niscus 



Medial longi 

 tudinal 

 fasciculus 



Masticator nerve 



Semilunar ganglion 



\." Sensory" nucleus of 

 trigeminus 



^____ Spinal tract and nucleus of 

 ^ ^ " / " ~ spinal tract of trigeminus 



Fasciculus proprius 



bran'^hes hpVnTl^r/ T T,^^^ '^Z'''"*' '^''^'"^^ ^o^^^^ni of the spinal cord. The ascending 



extZinn nnw!.fl f' V^ ""^ them termu.ate in the 'sensory nucleus,' and, therefore, thi 

 both shnJnn.l *° ^'"^ nicsonccphalo,, of the nucleus of termination of the trigeminus is 

 Doth shorter and more scant than the si)ui!d cxtonsion 



of m«X^l!rT ^^"^ Tl'l!'"'' ""^ ^■^""'"'^♦'"" '.'f the trigeminus arc distributcd-a) to the nuclei 

 ot masticator nerve of the same and opposite sides (short or simple reflex fibres); (2) to the 



