43 



titifoid is much elonc^.ated. It lies parallel with the marP'in of 

 the cell. Tigroid masses are continued far along the dendrites, 

 even into the tertiary branches. They are disposed parallel 

 with the course of the dendrites. 



In that side of the cell from which the axone arises, 

 the tigroids have a special arrangement. The axone-hillock 

 (Fig. 47, ax. h. ) is an oval mass of finely granular material, 

 and the tigroid-bodies are packed rather densely round it. 

 The form of tigroid is also less elongated here, merely an 

 irregular lump. 



The axone arises directly from the body of the cell. While 

 it is destined to ultimately be a component of either the V, 

 VII, IX, or X nerves, it generally takes quite an indirect 

 course. The usual way is through the mediun of the fasciculus 

 longitudinalis dorsalis. An axone passes into this bundle 

 to finally emerge at some other level. In Pig. 47, the axone 

 passes dorsal to the fasciculus communis. There is a bundle 

 of fibres of considerable size lying here, composed chiefly 

 of axones which have emerged from the dorsal longitudinal bundle 

 to enter the nerve-root. Other axones, but these are few in 

 number, may enter the nerve directly. Still others pass into 

 a bundle of arcuate fibres and doubtless enter the nerve on 

 the opposite side. These several paths to the nerves are shown 

 in Pig.?, v.m.f. 



The viscero-motor neurones have an internal structure 

 which is conspicuously motor in character, the large amount 



