THE ADRENAL OR SUPRARENAL GLANDS. 



109 



FIG. 45. 



The cortex consists of columns or nodules of epithelium 

 (mostly without lamina), separated by delicate vascular con- 

 nective tissue. The epithelium-cells are polyhedral, granular, 

 and sometimes contain fat- 

 particles. According to the 

 arrangement of the epithelial 

 masses, the cortex is divided 

 into three zones : the zona re- 

 ticularis, zona fasciculata, and 

 zona glornerulosa, from with- 

 in outward. 



The zona reticularis, the 

 innermost zone, consists of a 

 network of epithelial columns 

 anastomosing with one an- 

 other. In the zona fascicu- 

 lata, which comprises the 

 largest part of the cortex, the 

 epithelial columns are straight, 

 parallel, radiating, and sepa- 

 rate from one another. In 

 the zona glomerulosa, w 7 hich is 

 next to the capsule, the epi- 

 thelial columns are apparently 

 coiled and convoluted, ap- 

 pearing on section as separate 

 rounded nodules. 



Capillaries and lymph-pas- 

 sages are abundant in the inter- 

 columnar cortical tissue, in 

 close relation with the epi- 

 thelium-columns, which pos- 



, Section of 



sess no basement-membranes. (Eberthi. 



The medulla of the adrenals 



is quite distinct from the cortex and consists of epithelial 

 masses and abundant bloodvessels, lymphatics, and nerves, 

 supported in delicate connective tissue. The epithelium is 

 arranged in branching and anastomosing nodules and columns 

 or closed tubes ; the cells are polyhedral or columnar. Capil- 

 laries are numerous and large venous sinuses are present. 



human adrenal gland 

 (Eberth). 1, cortex; 2, medulla. 



