SECRETION OF THE DUCTLESS GLANDS. 801 



(rabbit) in which the medulla persisted, and in which the grafted 

 gland preserved the animal from the usual fatal result following 

 total extirpation. It seems probable that if the method of grafting 

 is perfected the procedure may prove effective as a therapeutical 

 means in the treatment of Addison's disease. 



The Physiological R61e of the Adrenals. There seems to be 

 no question that the medullary substance forms epinephrin or adre- 

 nalin or some related compound which has a marked stimulating 

 effect upon the tone of the blood-vessels and upon the heart, and 

 that this material passes into the blood. The general view, there- 

 fore, has* been that one at least of the functions of the adrenals is 

 the internal secretion of this material. It is assumed that its con- 

 tinued formation is necessary to the maintenance of the normal 

 metabolism of the muscular tissues either by a direct effect or 

 indirectly by influencing the activity of the nerve centers. Removal 

 of this secretion results in a marked loss of muscular tone and vigor, 

 exhibited by the blood-vessels, the heart, and the skeletal muscles, and 

 death follows rapidly. This general view is in accord with the 

 facts so far as they are known, but it must be confessed that it goes 

 somewhat beyond the facts. Another permissible, although less 

 probable view is that the adrenals produce an antitoxic substance 

 whose function is to neutralize or destroy certain (unknown) poi- 

 sonous products of body metabolism. Removal or disease of the 

 adrenals, on this theory, causes death because it allows these 

 toxic products to accumulate. It should be noted that this sug- 

 gestion regarding the functions of the adrenal glands refers only 

 to the medullary portion, in which alone the substance caus- 

 ing a rise of blood-pressure is found. Regarding the functions of 

 the relatively large cortical portion of the gland we have no 

 definite information, although some comparative observations 

 indicate that it may have important specific relations to the growth 

 of the body, particularly of the genital organs. 



Pituitary Body. This body is usually described as consisting 

 of two parts, a large anterior lobe of distinct glandular structure 

 and a much smaller posterior lobe whose structure is not clearly 

 known. The cells are said to form follicles which contain some 

 colloid material.* Embryologically the two lobes are entirely dis- 

 tinct. The anterior lobe, which may be designated as the hypoph- 

 ysis cerebri, arises from the epithelium of the mouth, while the 

 posterior lobe, or the infundibular body, develops as an outgrowth 

 from the infundibulum of the brain, and in the adult remains con- 

 nected with this portion of the brain by a long stalk. Ho well f and 



* Thorn, 'Archiv f. mik. Anat ," 57, 632, 1901. 



f "Journal of Experimental Medicine," 3, 245, 1898; also Schaefer and 

 Vincent, "Journal of Physiology," 25, 87, 1899. 

 51 



