934 



THE CENTRAL NERVOUS SYSTEM 



' rut/ was impregnated, whelped at full term in an entirely normal 

 manner, and manifested the maternal instincts in their full intensity. 

 Flourens put forward the doctrine that the cerebellum is an organ 

 concerned in the co-ordination of movements, and especially the 

 maintenance of equilibrium, supporting his conclusions by an 

 elaborate series of experiments. Notwithstanding the very large 

 amount of experimental and clinical study which has been devoted 

 to the cerebellum since the time of Flourens, our actual knowledge 



Fig. 373. Cerebellar Cortex: Section in Direc- 

 tion oi Lamina (Cajal). a, Purkinje's cell; 

 b, granule cell in inner layer; c, dendrite of 

 a granule cell; d, axon of a granule passing 

 into the molecular layer, where it bifur- 

 cates into two fine longitudinal branches 

 (Golgi's method). 



Fig- 374 Cerebellar Cortex : 

 Section across a Lamina 

 (Cajal). a, Purkinje's cell; 

 the numerous dots in the 

 molecular layer represent 

 cross-sections of the bifur- 

 cated axons of the granule 

 cells (Golgi's method). 



of its functions had not until recently greatly advanced beyond the 

 point then reached. Some of the more modern authorities restrict 

 its influence entirely to the actions on which equilibration depends ; 

 others extend it to all volitional movements. Luciani looks upon 

 it as ' an organ which by processes that do not awaken conscious- 

 ness exerts a continual strengthening (reinforcing) action upon the 

 activity of all other nerve-centres.' Sherrington conceives of the 

 cerebellum as the head ganglion of the proprio-ceptive system 

 i.e., of the system of neurons whose receptors lie not on the surface, 



