124 



ANATOMICAL AND PHYSIOLOGICAL STUDIES ON 



No other author reports such a high degree of the inward 

 shifting of the organ. I have not studied the pig, but in the 

 rat I get the average distance between the labium vestibulare 

 and the inner edge of the head of the inner pillar cell as follows 

 'table 93). 



TABLE 93 



Average distance betiveen the labium vestibulare and the inner edge of the inner 



pillar cell — in ju (albino rat) 



Therefore, in the rat the organ moves inward on the average 

 of 23 \i; that is, in the ratio of 1:0.16 of the maximum distance 

 between these two points. It may be noted that the difference 

 in this table is not the same in the several turns, but diminishes 

 from base to apex— a relation which is the reverse of that reported 

 by Hardesty ('15) in the pig. I have no explanation for these 

 differences except their possible dependence on the different 

 animals used. 



C. On the growth of the largest nerve cells in the ganglion spirale. 



Observations. For the present studies the fourteen age groups 

 used in the previous observations on the growth of the tympanic 

 wall of the cochlear duct were employed. In order to see the 

 relation between the growth of the papilla spiralis and the cells 

 of the ganglion spirale, both studies were made on the same 

 sections. In addition, however, I made cross-sections of the 

 cochlea (i.e., at right angles to the axis) in several age groups 

 to follow the growth and the changes in the form of the nerve 

 cells as they appear in this plane. The data for the animals 

 thus used arc given in table 94. 



