FUNCTIONS OF THE CEREBELLUM. 527 



Besides the grey substance on the surface, however, 

 there is near the centre of the white substanceof each 

 hemisphere, a small capsule of grey matter called the 

 corpus dentatum (fig. 141, cd), resembling very closely the 

 corpus dentatum of the olivary body of the medulla oblon- 

 gata (fig. 141, 0). 



The physiology of the cerebellum may be considered in 

 its relation to sensation, voluntary motion, and the instincts 

 or higher faculties of the mind. It is itself insensible to 

 irritation, and may be all cut away without eliciting signs 



Fig. 141.* 



of pain (Longet ). Yet, if any of its crura be touched, pain 

 is indicated ; and, if the restiform tracts of the medulla 

 oblongata be irritated, the most acute suffering appears to 

 be produced. Its removal or disorganization by disease is 

 also generally unaccompanied with loss or disorder of 

 sensibility ; animals from which it is removed can smell, 



* Fig. 141. Outline sketch of a section of the cerebellum showing 

 the corpus dentatum (from Quain). . The section has been carried 

 through the left lateral part of the pons, so as to divide the superior 

 peduncle and pass nearly through the middle of the left cerebellar hemis- 

 phere. The olivary body has also been divided longitudinally so as to 

 expose in section its corpus dentatum. c r, crus cerebri ; /, fillet; q, 

 corpora quadrigemina ; s p, superior peduncle of the cerebellum divided ; 

 mp, middle peduncle or lateral part of the pons Varolii, with fibres 

 passing from it into the white stem ; a v, continuation of the white stem 

 radiating towards the arbor vitse of the folia ; c d, corpus dentatum ; o, 

 olivary body with its corpus dentatum ; p, anterior pyramid. 



