ORIGIN OF THE CEREBRAL NERVES. 



485 



the fifth ; and, on the other, the nucleus he observed to be con- 

 nected with the gelatinous substance is not the nucleus of the 

 fifth, but the inferior nucleus of the facial nerve. He does not 

 allude to any connection as existing with the lowermost point 



Fig. 253. 



Fig. 253. Transparent transverse section from the pons of Man, at 

 the planes of origin of the great root of the fifth : the right half of 

 the figure represents a somewhat lower plane than the left. A, Supe- 

 rior peduncle of the cerebellum (Bindearm) ; L, the posterior longi- 

 tudinal fasciculi beneath the grey floor of the fourth ventricle, the 

 left overlaid with fasciculi of the fifth nerve proceeding from the 

 raphe ; 7, fasciculi of the root of the facial posterior to the pos- 

 terior longitudinal fasciculi, and continuous internally with the fibras 

 rectae of the raphe, and running in close connection with descending 

 fasciculi of the fifth; B, the middle peduncle of the cerebellum 

 (Briickenarm) ; F M, the motor area of the posterior division of the 

 pons ; ar, fibrae arcuatse ; H, the raphe ; S, the region in which the 

 inferior lamina of the fillet bends round ; g, the gelatinous substance 

 of the origin of the fifth ; 5 a, the great root of the fifth ; 5 6, the in- 

 ternal descending roots of the fifth ; 5 c, external descending roots of 

 the fifth ; 5 d, roots of the fifth proceeding from the cerebellum ; 5m, 

 nucleus of origin of the small root of the fifth ; Q, transverse section 

 of the ascending roots of the fifth that lie just external to the fasciculi 

 of the latter at their point of emergence ; 0, region of the superior 

 olivary body. 



of the true motor root of the fifth, which I recognize in section 

 as a small cluster of cells situated not unfrequently at a con- 

 siderable distance behind the inferior nucleus of the facial. On 



