HORMONES 49 



which is produced by a few ounces of glan- 

 dular tissue in our necks. 



Another important set of organs in the pro- 

 duction of hormones are the adrenal bodies. 

 These are paired, gland-like bodies situated 

 in the fat, one at the anterior margin of each 

 kidney ; hence their name. Each adrenal body 

 consists of an outer, firm, yellowish layer, the 

 cortex, and of an inner, soft, gray or brownish 

 mass, the medulla. Like the thyroid, the ad- 

 renals are unprovided with ducts. As already 

 mentioned, their removal from an animal is 

 invariably followed by its death in a few days 

 or even hours. They have long been known to 

 be associated with an obscure, fatal disease, 

 known as "Addison's Disease," which is 

 marked by the appearance of bronze patches 

 upon the skin. From their medullary portion 

 there has been extracted a substance variously 

 named epinephrin, adrenin, or adrenalin, and 

 capable of producing profound bodily changes. 

 This substance is apparently normally present 

 in the blood in very small amounts. If a strip 

 of intestine is placed in a warm oxygenated 

 Kinger's solution, it will show rhythmic con- 

 tractions. If, now, to one hundred million 

 parts of this solution only one part of adre- 



