PLATE 3 



EXPLANATION OF FIGUKES 



10 to 14 These figures illustrate the difference in the coagulability of the Nissl 

 substance in the large and small spinal ganglion cells of the guinea-pig and mon- 

 key. All, except figure 11, have been drawn from specimens prepared by Bensley's 

 method. Figure 11 is from a guinea-pig's spinal ganglion, fixed in Carnoy's 

 6:3:1 fluid and stained with anilin fuchsin methyl green (p. 15). 



10 Four cells from a single section of a guinea-pig's spinal ganglion, prepared 

 by Bensley's method, showing the graduation between the diffuse Nissl sub- 

 stance (n.) in the small cells {a and h) and the sharply defined Xissl bodies in the 

 large ones (c and d). The mitochondria (to) are the same in both types of cells 



(p. 14). 



11 Two cells from the spinal ganglion of a guinea-pig fixed in Carnoy's 6:3:1 

 fluid and stained with anilin fuchsin methyl green. Here the Nissl substance (n) 

 is present in the form of discrete granules in both the large and the small cells. 

 The mitochondria are absent, having been destroyed by the fixative (p. 15). 



12 From a small spinal ganglion cell in direct contact with the large cell 

 illustrated in figure 10 d. The Nissl substance within it is present as a diffuse 

 deposit (p. 14). 



13 Two small spinal ganglion cells of a monkey (same animal as fig. 2) to show 

 that the diffuse Nissl substance often stains with variable intensity. It is much 

 lighter in (o) than in (6) (p. 15). 



14 Spinal ganglion cell, from the same preparation, also showing the diffuse 

 Nissl substance in) axone fp. 15). 



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