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STUDENTS HISTOLOGY 



cesses, of which there may be one or many. According to the 

 number of processes, the cells are sometimes named unipolar, 

 bipolar, or multipolar. Every ganglion-cell has a relatively straight 

 process, which is the axis -cylinder process. The other processes, 

 when they are present, divide and subdivide rapidly, to form fine 

 networks or arborizations. They are called protoplasmic processes, 



FIG. 139. TYPES OF GANGLION-CELLS AS SHOWN BY GOLGI'S METHOD. (BAKER.) 



A. Type I. * Axis-cylinder process with collaterals. 



B. Type II. * Axis-cylinder process. 



or dendrites. The development of protoplasmic processes is seen in 

 an extreme degree on the ganglion -cells of Purkinje in the cere- 

 bellum (Fig. 158). It is probable that the processes of one cell do 

 not unite with those of any other, and that whatever physiologi- 

 cal relations the cell has with other cells are established through 

 proximity, but not by continuity of substance. The researches 

 made according to Golgi's method of impregnating tissues with 

 silver have shown that ganglion-cells are of two principal types : 



