PLATE 1 



EXPLANATION OF FIGURES 



1 to 12 Showing in a semidiagrammatic way the three arrangements of the 

 stainable substance in four age groups of the largest cells in the gasserian gan- 

 glion of the albino rat. 



Arrangement A in figures 2, 5, 8, 11. 



Arrangement B in figures 3, 6, 9, 12. 



Arrangement C in figures 1, 4, 7, 10. 



Enlargement, X 600. 



268 



