Anatomy, Embryology, Compara- 

 tive Anatomy, and Histology 

 of the Suprarenals 



E. V. COWDRY 



NEW YORK 



Anatomy 



Gross Morphology and Relations. Like most endoerin organs, the 

 suprarenals are subject to great variation. They weigh together about 

 eight or nine grams. In women they are rather smaller than in men. Of 

 the two, the left is usually the larger ; but the difference is referable chiefly 

 to the cortex. On section the outer, cortical part can easily be dis- 

 tinguished by its yellowish color, which is due to its contained fat and 

 lipoid. The medullary portion, by reason of its greater vascularity, is 

 reddish brown. Each suprarenal fits like a cap on the mesial anterior 

 pole of the kidney (Fig. 1). Their ventral relations with respect to the 

 abdominal cavity differ. The left suprarenal gland is covered with peri- 

 toneum and is associated with the spleen, the stomach, and the tail of the 

 pancreas. It is sometimes in contact with the splenic artery and vein. 

 The right suprarenal is in relation with the liver, the inferior vena cava, 

 and the duodenum. Both of them rest posteriorly upon the diaphragm 

 and laterally upon the kidneys. They possess a slight but firm capsule, 

 and are embedded in the renal adipose tissue. Each has a definite hilus on 

 its anterior surface, through which the chief suprarenal vein leaves the 

 gland. 



Accessory Suprarenals. Accessory suprarenal glands are of common 

 occurrence. Strictly speaking, they contain both cortical and medullary 

 substance, but they may consist of either alone. When they consist of 

 medulla only, they should perhaps be classified with the other persistent 

 sympathochromaphil tissue. They are quite small in size, seldom more 

 than one centimeter in diameter. While they may occur in almost any 

 part of the abdomen, they are usually found in the neighborhood of the 



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