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A MANUAL OF VETERINARY PHYSIOLOGY 



and efferent fibres ; the afferent fibres — viz., fibres afferent for 

 the cerebellum — are found microscopically to consist of two 

 varieties, which, from peculiarities in their arrangement and 

 distribution, are known as ' moss ' and ' tendril ' fibres. The 

 1 moss ' fibres terminate by branching in the nuclear layer of the 

 grey matter, while the ' tendril ' fibres pass into the molecular 

 layer, and arborise by climbing around the dendrites of the 



Fig. 143. — Cerebellar Cortex : Section 

 in direction of lamina (cajal).] 



A, Outer or molecular layer; B, inner, 

 nuclear, or granular layer ; C, white matter. 



a, Purkinje's cell ; b, granule cells of inner 

 layer ; c, dendrite of a granule cell ; d, axon 

 of a granule cell passing into the molecular 

 layer, where it bifurcates into two fine 

 longitudinal branches (Golgi's method). 



Fig. 144. — Cerebellar Cor- 

 tex : Section across a 

 Lamina (Cajal). 



a, Purkinje's cell ; the numerous 

 dots in the molecular layer 

 represent cross-sections of the 

 bifurcated axons of the granule 

 cells (Golgi's method). 



cells of Purkinje. The efferent fibres are the axons of the cells 

 of Purkinje, which are essentially efferent in function. The 

 above outline affords some notion of the complexity of the struc- 

 ture of the cerebellum ; it is anticipating matters to say that this 

 body is an important reflex arc, but it is evident from its structure 

 how well it is arranged for reflex processes. 



The cerebellum, by means of its three peduncles, is brought 

 into connection directly or indirectly with all the other parts of 



