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HANDBOOK OF PHYSIOLOGY. 



part of the nervous system, have been determined by physiological ex- 

 periment, by pathological observation, and by its comparative anatomy. 

 (1.) With the exception of its middle lobe, it is itself insensible to 

 irritation, and may be all cut away without eliciting signs of pain 

 (Longet). Its removal or disorganization by disease is also generally un- 



FIG. 364. Vertical section of dog's cerebellum; p m, pia mater; p, corpuscles of Purkinje, which 

 are branched nerve-cells lying in a single layer and sending single processes downwards and more 

 numerous ones upwards, which branch continuously and extend through the deep "molecular 

 layer " towards the free surface; g, dense layer of ganglionic corpuscles, closely resembling nuclear 

 layers of retina; /, layer of nerve-fibres, with a few scattered ganglionic corpuscles. This last layer 

 ( // ) constitutes part of the white matter of the cerebellum, while the layers between it and the 

 free surface are gray matter. (Klein and Noble Smith.) 



accompanied by loss or disorder of sensibility; animals from which it is 

 removed can smell, see, hear, and feel pain, to all appearance, as per- 

 fectly as before (Flourens ; Magendie). Yet, if any of its crura be 



