Literary Notices. xxxi 



tic thalamus, and an afferent tract, which appears to be the cerebellar 

 termination of the antero-lateral ascending tract of Gowers. 



Lateral lobe extirpation, or section of the middle peduncle, was 

 followed by diminution of the transverse fibres of the pons Varolii on 

 the side of the lesion, and atrophy of the cells of the nucleus pontis 

 on the opposite side. 



Lateral lobe extirpation, or section of the inferior peduncle, 

 demonstrated the existence of an efferent tract to the opposite inferior 

 olivary body, and of an afferent tract to the cortex, chiefly of the lat- 

 eral lobe. 



Extirpation of the middle lobe occasioned no degeneration in the 

 superior, middle, or inferior cerebellar peduncles, but was followed 

 by degeneration and sclerosis of the tract which passes from the verm- 

 iform process to Deiters' nucleus — the " direct sensory cerebellar 

 tract " of Edinger. 



We were unable to confirm Marchi's statements as to the existence 

 of a direct efferent cerebellar tract in the spinal cord, or of degenera- 

 tion in the anterior nerve roots, mesial fillet, or posterior longitudinal 

 bundles, after cerebellar extirpation. 



In two cases of lateral lobe extirpation, however, we obtained de- 

 generation in the anterior and lateral columns of the spinal cord re- 

 spectively, in the position indicated by Marchi. In the case, however, 

 in which there was a marginal degeneration in the anterior column, 

 the nucleus of Deiters, on the same side, was implicated ; while, in 

 that in which degeneration in the lateral column was present, there 

 was a lesion of the tegment of the pons, involving the nucleus of the 

 lateral fillet. The same degeneration was induced by lesions specially 

 made in the lateral fillet. 



Destruction of the clavate and cuneate nuclei was followed by de- 

 generation, on the one hand, through the restiform body into the cer- 

 ebellum ; and, on the other hand, through the internal and middle ar- 

 cuate fibres to the opposite interolivary layer and mesial fillet. This 

 latter structure was traced to the anterior quadrigeminal bodies and 

 optic thalamus. 



Owing to lesion in some of the experiments of. the roots of the 

 5th cranial nerve, we were led to make special investigations on its 

 central connexions. Degeneration and sclerosis of the so-called "as- 

 cending root" was traced as far as the 2d cervical nerve, after section 

 of the sensory division; and atrophy of the so-called "descending 

 root" was observed after section of the motor division. We were 

 unable to confirm the existence of a direct cerebellar root to this nerve. 



