THE DENTATE NUCLEUS. 



83 



biventral has become distinctly bifid. The nucleus dentatus does not extend far 

 into the lateral part of the hemisphere, and the superior cerebellar peduncle is no 

 longer cut ; but fibres are seen streaming from the white centre of the hemisphere 

 into the middle and inferior peduncles. The general conformation of the section 

 is somewhat altered, but the number and relations of the sub-divisions of the 

 hemisphere is not materially different, and the several branches of the arbor vitee 

 and the more important fissures are readily recognizable. 



Nuclei in the white matter of the cerebellum. The dentate nucleus 

 (corpus ciliare, corpus dentatum) of the cerebellum (figs. 59 C, and 60, n.d.), very 



n.gZobosu.s 



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Fig. 60. SECTION ACROSS THE CEREBELLUM AND MEDULLA OBLONGATA SHOWING THE POSITION OP THE 



NUCLEI IN THE MEDULLARY CENTRE OF THE CEREBELLUM. (Stilling.) -f. 



n.d., nucleus dentatus cerebelli ; s., band of fibres derived from restiform body, partly covering the 

 dentate nucleus ; s.c.p., commencement of superior cerebellar peduncle ; com', com", commissural fibres 

 crossing in the median white matter. 



similar to that already described in the olivary body of the medulla oblongata, 

 presents the appearance of a waved line of compact yellowish brown substance, 

 containing white matter within. The wavy character is more apparent in horizontal 

 than in vertical sections through the hemisphere. The line is interrupted at its 

 anterior and mesial part (hilum), where the superior cerebellar peduncle emerges 

 from it. The dentate nucleus may be described as consisting of a plicated pouch or 

 capsule of grey substance open at one part and enclosing white matter in its interior, 

 like the dentate nucleus of the lower olivary body. 



In addition to the corpus dentatum certain other portions of grey matter, which 

 have been only more recently recognised, are found in the white centre of the 

 cerebellum (Stilling). They are three in number on each side and are termed 

 respectively the nucleus emboliformis, nucleus globosus, and nucleus fastigii (figs. 60. 

 61). The nucleus emboliformis is a small clavate mass of grey substance lying 

 mesially to and partly covering the hilum of the dentate nucleus. On the inner side 

 of the nucleus emboliformis, between it and the middle line, is a streak of grey 

 matter passing antero-posteriorly and ending behind in an enlarged extremity. This 

 has been named the nucleus globosus. Finally, close to the middle line, where 



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