162 'Journal of Cornparative Neurology and Psychology. 



somewhat lower than my figures. The great disparity between 

 my results and those obtained by Schiller is probably due to the 

 less perfect technical methods at his command. 



2. The number of cases is too small to make a reliable com- 



NO.OF 

 FIBRES 

 10000 r 



FiG.m. 



6000 



6000 



4000 



2000 - 



O 



BODl" WEIGHT 



_i I 



Gikd:s. 600 1200 1800 2400 3000 



Fig. 3. The increase in the number of medullated fibers in the oculomotor nerve of the cat. 



parison between the relations of age and of body-weight, respec- 

 tively, to the increase in the number of fibers. 



3. Although we do not observe in this series the same degree 

 of constancy in the number of " large " fibers that we observe in the 



