896 



THE CEREBELLUM. 



especially in the right. When suspended, the animal now exhibits less 

 pleurosthotonus (concavity, to the right). The right forepaw often lies 

 folded in the supine position, a sign significant of paresis. It can now be 

 seen, if the animal tries to raise itself on its fore-limbs, that tremor, which 

 may be present even when the animal is at rest, prevents the attempt, 

 becoming very severe. The hind-limbs seem weaker than the fore-limbs, 

 but the extensor rigidity is more marked in the fore-limbs (in the dog and 

 cat, etc. ; in the monkey (Luciani, Terrier and Turner) the rigidity 

 assumed is flexor, not extensor (at elbow and knee). Some days later the 

 power to stand is regained, the fore-limbs becoming able to carry the 



FIG. 363. Posture assumed after removal of the right half of the cerebellum. 

 Thomas (from an instantaneous photograph). 



body earlier than the hind-limbs. When first attempting to walk, the 

 hind-quarters drag or crouch, so that in the latter case the rump stands 

 lower than the shoulder. Tremor and lateral oscillation, especially of 

 neck and trunk, disturb every effort. If an obstacle be met in walking, 

 the tumble occurs to the right, although the right limbs are widely 

 abducted. Progression follows not in a straight line, but the main 

 direction is broken by curves, is " festooned " to the right. The paces 

 taken by the widely abducted legs are short. The whole gait is a 

 reeling one. The right paws are lifted and set down again with an 

 abnormal abruptness and with exaggerated muscular action, as compared 

 with the less abnormal side. The knee-jerk is often found to be more 



FIG. 364. Foot-prints of a normal dog. p, walking ; g, galloping. Luciani. 



brisk on the homonymous side. Placed in water, the animal swims 

 better than it can walk ; in swimming, the direction of progression is 

 curved toward the left ; the left side of the body is plunged deeper than 

 the right. In attempting to walk up steps, the left foot is used first. 

 After the eyes are bandaged, any attempt to remove the bandage is made 

 with the left foot. 



The head and neck are at every effort so disturbed, by swaying and 

 tremor, that feeding is impossible unless the head be held fixed for it. 

 The muzzle is plunged deeply into the food, or sways about helplessly 

 over it. The inco-ordination is not obviously increased by bandaging 



