160 ANATOMICAL AND PHYSIOLOGICAL STUDIES ON 



ages, after which the values are nearly constant. This means 

 that after birth the size of the cell bodies and their nuclei does 

 not increase so much as do those of the spiral ganglion cells, 

 or, expressed in another way, the cells in the vestibular ganglion 

 have developed earlier than those of the spiral ganglia and at 

 birth have already attained nearly their full size. 



On the comparison of the diameter of the cell bodies and their 

 nucei in the nerve cells of he ganglion vestibulare according to sex. 

 For this purpose twelve age groups of albino rats were used. 

 In seven cases we have two cochlea in each group in the same sex, 

 in which the average value is recorded. In table 116 are entered 

 the values for these diameters and at the foot of the table the 

 data are analysed. They reveal no evidence of a significant 

 difference in the diameters according to sex. 



On the comparison of the diameters in the cell bodies and nuclei 

 of the nerve cells in the ganglion ves ibulare according to side. For the 

 present study fourteen age groups were employed. As indicated 

 in table 117, the data in five instances are based on the average 

 of two cochleas of the same side. Table 117 enables us to make 

 the comparison of the diameters of the cell bodies and their 

 nuclei on both sides, and the analysis of the data given at the 

 bottom of the table shows that there is no difference in these 

 characters according to side. 



On the morphological changes in the cells of the vestibular ganglion. 

 Figure 14 illustrates semi-diagrammatically the ganglion cells 

 in the vestibular ganglion of the albino at birth, 20 and 367 days 

 of age. These figures, as in the ganglion spirale, have been 

 magnified 1000 times and the absolute values of the diameters 

 are given in table 115. 



As seen in figure 14, both the cell body and the nucleus are at 

 birth already well developed and more precocious in their develop- 

 ment than the cells in any of the other cerebrospinal ganglia 

 thus far examined. The cytoplasm is relatively abundant and 

 the Xissl bodies are present, though both of these characters 

 become more marked later. 



The nucleus is also large, the chromatin somewhat differentiated 

 and the so-called 'Kernfaden' often occur. Generally speaking, 



