112 ADRENALS OK SUPRA-RENAL CAPSULES, BY C. J. EBERTH. 



to the proper cortical substance. The medullary portion, which 

 is much more sparingly developed than in other animals, is 

 here only represented by small isolated accumulations of 

 polygonal cells, which are superimposed on the cortical portion. 

 In its deeper parts the latter consists of branched and anas- 

 tomosing columns of cells that decussate with similar columns 

 of the medullary substance. Both the columns and the cell- 

 masses are destitute of a membrana propria. 



The structural relations are similar to the above in Saurians 

 and Chelonians. 



The web-like arrangement of the branched cortical and 

 medullary columns is still more distinctly marked in Birds. 

 Instead of the solid columns, however, cylindrical tubes of 

 narrow bore are found, which, like those of the cold-blooded 

 animals, do not form a perfectly closed plexus, but frequently 

 end csecally. The cells of these tubes are small cylinders with 

 excentric nucleus in the cortical portions, but more polymor- 

 phous, and usually cylindrical or polygonal, in the medullary. 



In Mammals the two substances are arranged in a laminated 

 manner. The external or cortical substance is greyish yellow, 

 or, if it contain much fat, whitish yellow, in colour, and 

 fractures in a radial direction. It invests the internal grey 

 medullary masses in the form of a capsule, and into these also 

 small portions of the cortex penetrate, accompanied by large 

 vessels. No medulla exists in the thin marginal portions of 

 the organ, but the innermost cortical layers here come into 

 contact, and form a simple brown stria. 



The accessory adrenals that are frequently found in con- 

 siderable number in immediate proximity to the chief organ, 

 in the form of yellowish granules, are detached portions of the 

 cortex, provided with a highly vascular nucleus of connective 

 tissue, 



In Man, as a result of decomposition, the innermost cortical 

 layers break down into a semi-fluid mass. Under such 

 circumstances a cavity is found between the medulla and the 

 cortex, filled with a pultaceous material composed of blood and 

 disintegrated cortical substance. 



CORTEX. In the Cortex, from two to three distinct layers 



