94 



PIGMENTARY GROWTH AFTER ABLATION OF 



In order to determine accurately the diminution in the adrenal 

 cortex in the albino and its increase in the thyroidectomized 

 tadpole, this substance was accurately drawn with the camera 

 at a magnification of 300 diameters in three specimens, a 67-mm. 

 albino, a 56-mm. thyroidless tadpole, and a 42-mm. normal 

 animal. The drawings were transferred to a wax plate of pro- 

 portionate thickness and the weight of the models of the cortex 



TABLE 9 



Table giving the weight of wax models {XSOO) of cortex of left adrenal (frog tadpoles) 



'■ The length of the component parts of the tadpole is given in the following order: 

 Total /Hind/Fore 

 Body /Tail/legs /legs 



thus secured for these three specimens (table 9). The cortical 

 substance of one adrenal — the left in each case — was treated in 

 this way The albino, although 11 mm. longer than the thy- 

 roidectomized tadpole, and 25 mm. longer than the normal speci- 

 men, had but 38 per cent, of the cortical tissue presented by the 

 normal and 19 per cent, of that of the thyroidectomized speci- 

 men. It would thus appear to be established that the cortical 

 tissue is greatly diminished in the albino as compared with 



