150 AYALTER E. DANDY and EMIL GOETSCH 



the gland is removed by an operation conducted from under the 

 temporal lobe. It would be the first to suffer in all operations 

 such as those which have been employed in man in which the 

 gland is approached* from below through the sphenoidal cells. 



SUMMARY 



The anterior lobe receives its blood supply from about eighteen 

 or twenty small arteries which converge toward the stalk from 

 the various components of the circle of Willis. These vessels 

 immediately break up into numerous large sinusoidal channels, 

 in apposition with the cells and lined only by endothelium. Hence, 

 there are no veins or arteries proper in the anterior lobe. The 

 venous supply is very similar in arrangement to the arterial system; 

 the veins passing from the stalk to a venous circle immediately 

 overlying the circle of Wilhs and draining into the venae magnse 

 Galeni. 



The pars intermedia derives its supply from the vessels of the 

 stalk, from the adjacent brain, and from the posterior lobe. A 

 collateral therefore exists at this point between the anterior and 

 posterior lobes, probably sufficient to preserve the function of at 

 least the adjoining portion of either lobe if its individual supply 

 is cut off. 



The posterior lobe receives its arterial supply from a small 

 artery formed by the union of a symmetrical branch from each 

 internal carotid. One large vein and other small ones enter the 

 circular sinus immediately above the artery. 



The ''parahypophysis" has an individual blood supply of two- 

 fold origin; a posterior vessel from the union of two branches 

 from the pos-terior lobe arteries and a bilateral branch from the 

 internal carotid arteries. 



In concluding, it is a pleasure to express our gratitude to Dr. 

 Harvey Gushing for his suggestions during the course of the work, 

 and to Mr. Max Brodel for his instruction and advice in the prep- 

 aration of the accompanying drawings. 



