THE CHARACTERISTICS OF THE INDIVIDUAL NERVE CELL 



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most, cases a conducting organ, still those physiological processes which go on 

 in it produce marked changes in the protoplasm of the cell body. Hodge has 

 demonstrated that nerve cells which have been active for several hours, in 

 case of sparrows which have been flying about actively throughout the day, or in 

 bees after a day's work, show marked evidences of fatigue. These evidences 



B 



FIG. 356 A. Spinal Ganglion Cells from the Cat. A, Normal taken before stimulation; B, taken 

 alter five hours' stimulation. From the right and left, eight tnoracic ganglia. (Hodge.) 



consist in the decrease in the size of the nucleus and the appearance of 

 vacuoles in its structure, also in the shrinking of the protoplasm of the cell, 

 which, in case of the cells of the spinal ganglia, draws away from its capsule. 

 If the cells are examined early in the morning, then these fatigue changes will 

 not be present, the cell having recuperated during the rest of the night. It 



