138 WALTER E. DANDY and EMIL GOETSCH 



centre of the anterior lobe. It had been suggested by Paulesco 

 that stalk separation is equivalent to a total hypophysectomy, pre- 

 sumably as a result of such necrosis; and the experiences in this 

 laboratory tended at first to confirm this view. Later observa- 

 tions, however, have shown that although a stalk separation will 

 often lead to a certain degree of central necrosis of the pars an- 

 terior, total isolation of the gland, not only from the infundi- 

 bulum but from its dural attachments as well, is necessary before 

 the procedure becomes equivalent to a total removal; and even 

 in this case fragments of the structure, thus isolated, may under 

 favorable circumstances become revascularized in part, the opera- 

 tion therefore being comparable to a total homo-transplantation 

 of the gland into the tissues elsewhere. 



More complete information in regard to the sources of the gland- 

 ular blood supply has become essential to a better understanding 

 of these operative experiences, and at the suggestion of Dr. 

 Gushing these studies have been made with this end in view. 



The present paper deals with the mammalian circulation as 

 observed in the dog — the animal employed for most of the experi- 

 mental studies. It is presumable that the findings apply as well 

 to man, but we have had no suitable opportunity for a proper 

 injection of the human gland. 



PRIOR DESCRIPTION OF THE CIRCULATION 



The first mention in the literature of the pituitary circulation 

 is an incidental reference by Duret ('72) in his classical work 

 upon the blood supply of the brain in general. He refers to a 

 small bilateral branch which passes from the posterior communi- 

 cating artery to the infundibular wall. Heubner, two years later, 

 made a similar reference. 



From the time of these casual comments, although it was 

 generally appreciated that the anterior lobe was a very vascular 

 organ and contained peculiar sinusoidal spaces, the subject has 

 been given little attention, until Herring's recent excellent and 

 concise description of the internal circulation of the cat's hypophy- 



