132 THE SPINAL CORD AND CEREBELLUM 



' The condition is one not so much of absolute loss 

 of power as of imperfect action.' ' The imperfect 

 action has been described under the general term 

 " inco-ordination," but has been analyzed, though all 

 observers are not agreed in this, on the one hand into 

 diminished power — that is to say, energy of contraction 

 (parasthenia), which in the dog is most conspicuous 

 in the muscles of the hind-leg — and on the other hand 

 into a diminished tone (paratonia) and an unsteadi- 

 ness of contraction due to the occurrence of small 

 and rapid though regular tremors (parastasia).' ' Ob- 

 viously,' he continues, ' there is something wrong in 

 the nervous machinery for carrying out the move- 

 ments, and especially perhaps the voluntary move- 

 ments of the right side.'* 



' Diseased of the cerebellum, uncomplicated by 

 lesions in other parts of the brain, in no way 

 interferes with psychical powers, and does not in the 

 least impair sensations, either special or general, but 

 it does interfere with the action of the skeletal 

 muscles. The disorder which it brings about— an 

 unsteady gait, the " cerebellar reel," not wholly unlike 

 that of drunkenness — is usually described as " inco- 

 ordination," but so far as it can be analyzed seems to 

 be of the same nature as that produced experimentally 

 in animals — the same diminution of power leading to 

 a difficulty in maintaining the erect posture, the same 

 diminution of tone and the same occurrence of 

 tremors have been observed.' 



* Foster, loc. cit., p. 1207. t Ihid., p. 1208. 



