THE NERVOUS SYSTEM 



445 



Some of the sympathetic cells are probably afferent but the nia- 

 jority are efferent. The fibres of the white rami communicantes are 

 mostly fine and medullated. The axones of the sympathetic cells are 

 fine and non-mcdullated or thinly medullated. For further details 

 see Fig. 310. 



The larger ganglia resemble the spinal ganglia in having a connec- 

 tive-tissue capsule and framework. The cells are smaller and often 

 densely pigmented. Each cell is surrounded by a capsule of cells 



Fig. 311. — Sympathetic Xerve Cells (woman of 36 years). (Cajal.) A and B, 

 cells whose dendrites {b) form a pericellular plexus. C, cell with long dendrites, a, 

 axone; c and d, terminal part of a dendrite. The capsular cells are fainth' indicated. 

 (Cajal's silver stain.) 



similar to those surrounding the spinal ganghon cells. Often two or 

 three cells and their interlocked dendrites are enclosed within a com- 

 mon capsule (Fig. ^12, A). 



The typical sympathetic nerve cell is a multipolar cell with short 

 branching dendrites confined to the capsule of the cell and often inter- 

 locked with the dendrites of adjacent cells, forming glomeruli. 

 Sometimes a dendrite will pass some distance from the cell, arborize, 

 and interlock with a similar dendritic arborization of another cell. 

 Another form of sympathetic cell has long slender dendrites often 

 indistinguishable from axones. These cells are more frequent in the 



