130 



ANATOMICAL AND PHYSIOLOGICAL STUDIES ON 



Figure 13 illustrates semidiagrammatically the nerve cells 

 in the spiral ganglion of the albino rat at 1 day and at 20 and 366 

 days. 



The body of the ganglion cells at birth is small and has the 

 characteristic fetal form. The cytoplasm is homogeneous and 

 scanty and the Nissl bodies are not yet seen. The nucleus forms 



TABLE 98 



Comparison according to sex of the diameters of the cell bodies and the nuclei in 



the ganglion spirale 



the greater part of the cell. The chromatin is not yet well 

 differentiated, and the so-called 'Kernfaden' are not visible. 



The sharply marked nucleolus is in most cases in the central 

 position, but sometimes located peripherally. 



The cytoplasm matures rapidly. At six days the Nissl bodies 

 appear, though they are of course, less abundant and smaller 

 than in the later stages. The nucleus develops also and the 

 chromatin is well differentiated. Thus the development in both 

 the cell body and the nucleus proceeds rapidly in the earlier 

 stage. 



