N 



I i 



Fig. 10. A small area from one of the fusiform, immature Leydig cells 

 illustrating the fibrillar character of the cytoplasm. Large numbers of 

 very thin filaments (50 a) are generally oriented parallel to the long 



axis of the cell. 

 Fig. 11. An area from a typical mature Leydig cell. The cytoplasmic 

 filaments have been replaced by enormous numbers of minute mem- 

 brane-limited vacuoles, giving the protoplasm a foamy texture. The sharp 

 angular structure above is the tip of a crystal (Cr), and the edge of the 



nucleus (N) appears at the lower right. 

 Fig. 12. A portion of an interstitial cell showing both filaments (F) and 

 small vacuoles (V). A fabric-like pattern is visible in the crystal (Cr) at 

 the left. The mitochondria (M) have a matrix of very low density and 

 the internal membranes are sparse and disorderly in their arrangement. 



