NORMAL HISTOLOGY. 













FIG. 82. 



processes is only apparent, being due either to mutilation or to the 

 process lying without the plane of the section ; where processes are 

 really wanting, an immature or pathological condition must be 

 suspected. 



The processes of nerve-cells are of two principal kinds the 

 protoplasmic (dendrits} and the axis- cylinder (neurits] processes. 



The protoplasmic processes 

 or dendrits rapidly undergo 

 division, splitting up and sub- 

 dividing until the resulting 

 branches form rich terminal 

 arborizations of slender 

 threads, which frequently 

 interlace, but probably jneve.r_ 

 ^actually _ join, with similar 

 fibrils of adjacent cells. 

 -Nerve-cells, in one sense, are 

 but nucleated local accumula- 

 tions of the interfibrillar pro- 

 toplasm, which latter may be 

 termed neuroplasm (K61- 

 liker) ; ~tfuT large' striated 

 multipolar ganglion-cells may 

 be regarded as switch-boards 

 for the redistribution of the 

 erous ultimate fibrillae 

 continued into the axis-cylin- 

 ders. The fibrillae pass off in 

 divergent paths, along the 

 several processes of the cell, 

 'to form new combinations and 

 relations. 



The peculiarities formerly 

 supposed to constitute the distinguishing characteristics of the 

 axis-cylinder processes are no longer sufficient in the light 

 of recent advances in our knowledge regarding the structure of 

 the nervous system. The investigations of Golgi and others have 

 shown that, in addition to greater delicacy and a straighter course, 

 the axis-cylinder processes present variations which separate gan- 

 glion-cells into two groups cells of the first and cells of the 

 second type. 



Nerve-cells of the first. type include elements, as those of the 

 motor areas, possessing the characteristic axis-cylinder processes 

 directly continuous with the axis-cylinder of the nerve-fibre. While 



Nerve-cell from the cerebral cortex, exhibiting the 

 striations of the protoplasm and the conspicuous char- 

 acter of the nucleus and the nucleolus : /, pigment- 

 granules ; a, axis cylinder process ; b, I, apical and 

 lateral protoplasmic processes. 





