I02 



BIOLOGY OF THE LABORATORY MOUSE 



upon the size and arrangement of the cells, the cortex may be divided into 

 three zones. Immediately beneath the capsule is the narrow zona glomeru- 

 losa formed by small cells arranged in arch-like groups. The cells have 

 relatively large nuclei and slightly basophilic cytoplasm. In the next zone, 

 the wide zona fasciculata, the cells are larger and are arranged in more or 

 less definite radial columns separated from each other by small blood 



Capsule 



omerulosa 



fasciculata 



^^ 



Zona reticularis 



^^f 



■:, -© 





y Medulla 



Fig. 4j. — Adrenal gland. P'ixed in Bouin's fluid. (X200.) 



vessels. The cells have vesicular nuclei, and the cytoplasm appears foamy, 

 due to the presence of finely distributed lipoid droplets. This zone mor- 

 phologically resembles the corpus luteum. The third zone, the zona 

 reticularis, is composed of strands of small cells which form a network 



(Fig. 43)- 



According to Howard-Miller (51), in the adult male mouse the fas- 

 cicular and reticular layers are not definitely limited, and their separation 

 into two zones is not justified. The same author observed that in the young 

 adult nulliparous female the zona glomerulosa and fasciculata are similar to 

 those of the male, but that in addition to these zones there exists a wide 

 third zone composed of cells which differ from the cells of the zona fas- 

 ciculata by being smaller and staining more intensely. She named this 



