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Herring 



epithelial columns surrounding it. The arrangement of these fibres is not 

 easily made out in Golgi preparations, but can be more readily followed in 

 thinner sections prepared by Cajal's reduced silver method. Cajal's method 

 shows that the posterior lobe is pervaded by a dense network of fibres which 

 agree in their manner of disposition with the arrangement revealed by the 

 Golgimethod,but are more uniformly stained than by the latter. Theependyma 

 fibres are large and thick in the adult cat, especially near their origin from 



/ V 



Fir;. 10.— Section of part of nervous substance of posterior lobe of the pituitary body 

 of an adult cat, showing neuroglia cells and fibres. Prepared by Cox's modification 

 of Golgi's method. 



the cell. They appear to begin abruptly in the cell protoplasm, often by 

 several rootlets, which soon fuse to form a single process or remain separate. 

 In the body of the posterior lobe the ependyma fibres take various courses. 

 Some run outwards and are lost in the neuroglial network. At the posterior 

 end of the lobe where the central cavity approaches the epithelial covering, 

 fibres may be traced outwards to end immediately under the latter. Most 

 of the ependyma fibres, and especially those of the anterior part of the lobe 

 and the neck, take a longitudinal direction, as though passing upwards and 

 forwards into the brain. The two layers already mentioned as occurring in 

 the neck of the infundibulum are particularly well defined by Cajal's 

 method. Fig. 12 is a drawing of a longitudinal section througli part of the 



