144 



ANATOMICAL AND PHYSIOLOGICAL STUDIES ON 



cells and the relation of their long axes to the axis of the cochlea. 

 Here also the ten largest cells in each of four, nearly corre- 

 sponding turns, were measured. We obtained the following 

 results : 



1 . As thus prepared, the ganglion cells at birth have a maximum 

 size of 11 x 10 [i in cell body and 8.2 x 7.6 [x in nucleus. At 

 twenty days the diameters are the largest, 18.7 x 16.9 [x in cell 

 body and 10.3 x 10.0 [x in nucleus. 



TABLE 112 



Analytical constants giving the mean, standard deviation and coefficient of vari- 

 ability with their respective probable errors for the diameters of the cells 

 and their nuclei of the ganglion spirale, in cross-section 



2. The ganglion cells grow relatively rapidly after birth and 

 reach at twenty days of age their maximum size. After having 

 passed the maximum at twenty days, they diminish in size 

 very slowly, but the internal structure matures more and more 

 with successive age. 



3. The nuclei are relatively large at birth but increase more 

 slowly than the cell bodies do; nevertheless, they follow the 

 same course of development as the latter. This peculiar course 

 in the growth of the ganglion cells is similar to that followed 

 by the cells of the lamina pyramidalis of the cerebral cortex 

 of the rat as found by Sugita ('18) 



