PARENCHYMA OF THE ADRENALS. 



Ill 



heaps of angular and slightly stellate cells that are sometimes 

 arranged in a single layer, and sometimes in many tiers. In 

 the interior of these cellular masses there is usually an 

 irregularly shaped cavity. It is still undetermined whether 

 a medullary substance is present or absent in the adrenals of 

 fishes. 



Fig. 154. 



Fig. 154. Irregularly shaped masses and columns of cortical sub- 

 stances from the adrenals of the Frog. 



In the adrenals of Batrachians, Saurians, Chelonians, and 

 Birds, the cortex and medulla are not arranged in layers 

 as in Mammals, but the two substances are placed side by side, 

 in rounded heaps, or in branched cords and columns. 



In the Batrachia the most superficial portions of these 

 organs are composed of solid roundish and elongated groups 

 of polygonal cells, filled with fat molecules. These correspond 



