18 



CHAPTER II. 

 THE PITUITARY GLAND. 



The effects of removal in animals Injection of extracts 

 Pituitary feeding Acromegaly and gigantism Frohlich's type 

 Functions of the pituitary gland Therapeutic value of pituitary 

 extract. 



IT \vill be remembered that this gland is lodged 

 in the sella turcica of the cranium, in an exceed- 

 ingly secluded position in the body, and it is only 

 recently that its functions have been recognized. 

 It may be that the interesting researches of Schafer, 

 Paulesco, Gushing, and others, will prove to have 

 opened up a very important and useful chapter in 

 medicine as well as in physiology. 



The gland consists of two distinct portions, anterior 

 and posterior, closely fused in man, but with a well- 

 marked line of junction in the dog. The anterior 

 part is glandular in structure, consisting of columns 

 of epithelial cells which generally contain colloid. 

 In young animals these cells line tubules ; later, 

 the central lumen disappears. Large blood sinuses 

 are present. The posterior lobe consists of vascular 

 neuroglia. Between it and the anterior lobe is a 

 cleft containing glairy fluid. The anterior portion 

 is derived from a pit in the dorsal wall of the pharynx 

 of the embryo ; the posterior is budded out from 

 the brain. We are thus prepared to expect a 

 difference in function. 



