THE ADRENAL BODIES 155 



Stilling found in rabbits, after extirpation of one adrenal, a 

 considerable increase in weight of the one which was left 

 behind. Pettit describes a similar hypertrophy in the cortical 

 adrenal (" corpuscle of Stannius ") in the eel, after the removal 

 of the glandule of the opposite side. 



But all observers could not record such hypertrophy. It is 

 probable that there is a difference in this respect between 

 different species. Harley among the older workers, and Poll 

 among the more recent, could not observe any such hypertrophy 

 in rats. There can be no doubt whatever that such a com- 

 pensatory hypertrophy may be regularly and easily observed 

 in the dog. 



The compensatory hypertrophy of accessory adrenals in 

 the rat, which is described by Wiesel, has already been discussed. 

 This may be related to the absence of hypertrophy on the part 

 of the chief organ. A similar hypertrophy of the accessory 

 adrenals which are found along the walls of the vena cava of 

 the guinea-pig has been described by Velich. 



According to some observers, the chromaphil cells, whether 

 of the adrenal medulla or of the extra-medullary corpuscles, 

 seem to be incapable of hyperplasia. If this really be the case, 

 it is interesting to compare the fact with another to be referred 

 to again later viz., that in grafting experiments it is only 

 the cortex which " takes " ; the medulla disappears. It is 

 possible that this lack of power of growth and of resistance to 

 absorption is related to the high degree of specialization of the 

 chromaphil tissues (Vassale). 



That the functional capacity of one adrenal left after the 

 removal of its fellow is not increased is the conclusion drawn 

 after some experiments by Battelli and Ornstein. These 

 authors removed one adrenal from dogs and rabbits, and let 

 them live for from two to seventeen days. After this period 

 the adrenin contents of the remaining gland were estimated by 

 Battelli's colorimetric method in order to obtain a measure of 

 the degree of vicarious function. No increase in the adrenin 

 of the remaining gland, but rather a decrease, was found. 

 These experiments, of course, have no bearing on the cortex of 

 the organ, but only on the chromaphil medulla. 



Elliott and Tuckett could not readily produce compensatory 

 hypertrophy. They found that the English guinea-pig cannot 

 survive the removal in one operation of a single gland. By 



