146 HUMAN PHYSIOLOGY. 



does not die. The above described symptoms may manifest themselves, 

 however, but they are slight in degree. 



The Hypophysis Cerebri. This is a small body lodged in the sella 

 turcica of the sphenoid bone. It consists of an anterior lobe, somewhat red 

 in color, and a posterior lobe, yellowish-gray in color. The former is much 

 the larger and partly embraces the latter. The anterior lobe is developed 

 from an invagination of the epiblast of the mouth cavity, and consists of 

 distinct gland tissue. The posterior lobe is an outgrowth from the brain, 

 and is connected with the infundibulum by a short stalk. It has been 

 suggested that the term infundibular body be reserved for the posterior lobe. 

 This distinction appears to be desirable, inasmuch as in their origin and 

 structure they are separate and distinct bodies. 



Removal of the hypophysis cerebri, or the pituitary body, is always fol- 

 lowed by a fatal result, preceded by symptoms not unlike those which 

 follow removal of the thyroid: viz., anorexia, tremors, spasms, etc. De- 

 generation of the hypophysis has been found in connection with a hyper- 

 trophic condition of the bones of the face and extremities, to which the term 

 acromegalia has been given. 



Intravenous injection of an extract of the hypophysis increases the force 

 of the heart-beat without any change in its frequency, and causes a rise 

 of blood-pressure from a stimulation of the arterioles (Schafer and Oliver). 

 The material secreted by the hypophysis has not been isolated, hence its 

 chemic features are unknown. After its formation it probably passes through 

 a system of ducts into the cerebrospinal fluid, after which it influences the 

 metabolism of the nervous and osseous tissues as well as the force of the heart 

 muscle. 



An extract of the hypophysis itself exerts no appreciable effect on the blood- 

 pressure or on the rate of the heart-beat, nor does it influence the circulatory 

 and respiratory organs (Howell). An extract of the infundibular body 

 intravenously injected, however, gives rise to increased blood-pressure and 

 to a slowing of the heart-beat 



Adrenal Bodies, or Suprarenal Capsules. These are two flattened 

 bodies, somewhat crescentic or triangular in shape, situated each upon the 

 upper extremity of the corresponding kidney, and held in place by con- 

 nective tissue. They measure about 40 mm. in height, 30 mm. in breadth, 

 and from 6 to 8 mm. in thickness. The weight of each is about 4 gm. 



Function of the Adrenal Bodies. It was observed by Addison that 

 a profound disturbance of the nutrition, characterized by a bronze-like 

 discolorization of the skin and mucous membranes of the mouth, extreme 



