ANIMAL AND VEGETABLE 



205 



and with varying tension, every cell is not of the same 

 structure or designed for the performance of the same 

 function. We must, therefore, examine them in detail and 

 have special regard to their formation, so far as it has been 

 made clear, or can be said to be suggestive to the electrician. 



Fig. 109. 



UNIPOLAR CELL from spinal ganglion of rabbit, a, axon ; b, circum- 

 nuclear zone, poor in granules ; c, capsule ; d, network within nucleus ; 

 c, nucleolus. (After Schafer.) 



Fig. 110. 



BIPOLAR CELL (ganglion) of fish (Holmgren). It will be noticed that 

 the medullary sheath is continued as a thin layer over the cell-body. 

 (After Schafer.) 



MULTIPOLAR CELLS. 



So far, the cells appear to be more or less globular in 

 shape, and while the multipolar cells of the cerebral cortex 

 and spinal cord appear to differ materially, as a whole, 

 from those of the unipolar and bipolar type, they must 

 obey the law, and therefore possess, although perhaps in 

 a modified form, the same internal arrangement or 

 arrangements and similar absolute capsular insulation. 



