278 SCIENCE PROGRESS. 



median section the gait, accurately studied by an ingenious 

 device of the experimenter, after some temporary disturb- 

 ance resembles in a few days the normal gait again. He 

 noticed that though the consequences of destruction of one 

 lateral half are severe, the further removal of the other half 

 hardly at all aggravates the symptoms except to make 

 their distribution bilaterally symmetrical instead of chiefly 

 unilateral. Each half of the organ depends little on the 

 other. After removal of one lateral half the dogf wheels con- 

 stantly toward the opposite side, and falls frequently, always 

 toward the side homonymous with the lesion. Its move- 

 ments are hindered on the homonymous side by want of 

 power and steadiness in the contraction of the muscles. 

 Luciani points out that the defective innervation of the 

 muscles is so fundamentally different from that obtaining" 

 after ordinary spinal or cerebral damage that the terms 

 paralysis and paresis employed for the latter are here unde- 

 sirable, since likely to confuse, and he rejects them lest the 

 appreciation of the profound difference be hindered. He 

 therefore in his description, according as it relates to the 

 tonus of resting- muscles, and to the force, the steadiness 

 and the mutual co-operation of contracting muscles, speaks 

 of an atonia, an asthenia and an astasia? as well as of the 

 ataxia so well known. Cerebellar lesion induces all of 

 these and chiefly on the homonymous side. Of the asthenia 

 he obtained numerical measurements by ingenious employ- 

 ment of a dynamometer. After removal of one lateral half 

 of the cerebellum the disuse of the limbs of the same side 

 was in some animals so great that they might at first sight 

 appear hemiplegic. In the dog the fore-limb became the 

 more ataxic, the hind-limb the more asthenic. Tremor 

 accompanied all muscular effort. The head shook when 

 the recumbent animal looked up on being aroused. 

 During progression the limbs and trunk muscles of 

 the homonymous side trembled rhythmically. In the 



1 Luciani uses the word astasia with a different meaning than that 

 given it by clinicians. He denotes by it want of steadiness of action in a 

 muscle. 



