478 PHYSIOLOGY CHAP. 



of excitation (1-2 per cent solutions) far exceeded that required to 

 evoke the typical spasms, when applied to the excitable zones of 

 the cerebral cortex and the dorsal horn of the cord. The more or 

 less diffuse symptoms of irritation are similar to those produced 

 by applying the poison in minute doses to adjacent parts of the 

 bulb. It is probable that the effects observed are due to the 

 spread of the poison to the centres in the dorsal surface of the 

 bulb, and consequently that the afferent elements of the cerebellum 

 are different in their nature from those of the cerebrospinal axis. 



The same negative results were obtained by Beck and Bikeles 

 (1912) on repeating these experiments with superficial application 

 of carbolic acid and strychnine. 



More exact results in accordance with the theory of cerebellar 

 localisations were to be expected from the method of partial and 

 localised extirpation of the different segments of the cerebellum. 



Our studies on the cerebellum aimed specially at formulating 

 the general function of this organ on an experimental basis, and 

 were confined to analysis of the components of the ataxy con- 

 sequent on more or less complete extirpation of one half, or of the 

 so-called vermis, or of the entire cerebellum. " From our researches 

 as a whole," we wrote in 1891, "it is plain that the different 

 segments of the cerebellum all have the same function. In fact, 

 the loss of the median lobe may in great measure be repaired, i.e. 

 organically compensated, by the lateral lobes; and, generally 

 speaking, whatever the cerebellar mutilation, symmetrical or 

 asymmetrical, circumscribed or extensive, the defect phenomena 

 do not differ intrinsically, but only in intensity, extent, and 

 duration, and in their more or less greater incidence on one or 

 other side of the body. . . . We cannot, therefore, regard the 

 cerebellum as a collection of functionally distinct or different 

 centres in the sense that each of its segments is in more or less 

 intimate or direct relation with a special group of muscles, or is 

 designed for functions of different character." 



Nevertheless, our investigations resulted in one definite fact 

 which paves the way to the theory of cerebellar localisation, viz. 

 that in dogs or monkeys the influence of each lateral half of the 

 cerebellum is mainly direct, that is, is exerted principally on the 

 muscles of the same side. Rolando's rudimentary experiments 

 established the same fact, and long before Rolando, in 1749, the 

 celebrated physician, Giovanni Bianchi of Rimini, had formulated 

 the same theory on a clinical observation, as we learn from 

 Bilancioni's interesting historical notice (1908). 



Terrier (1876) observed a fact which has a certain value in 

 relation to the theory of cerebellar localisation. He found that, 

 after the extirpation of the anterior portion of the vermis, monkeys 

 showed a tendency to fall forwards; after extirpation of the 



