H. B. van Dyke 



331 



Comparison of Ratio Value in Different Animals. 



A comparison of the ratio values of the thyroid glands of the 

 different animals so far examined is given in Table V. The few 

 abnormally high and unexplained ratio values are not included in 

 the table. 



From what data are available there appear to be some differ- 

 ences in the thyroid glands of different animals in the numerical 

 value of the ratio of the percentage of iodine in cells to that in 

 whole gland. The ratio value of iodine distribution for dog 

 thyroid glands seems to be consistently lower and more constant 

 than that for the thyroid glands of the other animals studied. 



TABLE v. 



A Comparison of the Value of the Ratio of the Percentage of Iodine in Cells 



Free from Colloid Material to the Percentage of Iodine in Whole 



Gland in Different Animals. 



* Tatum. 1 



t Only two glands analyzed. 



SUMMAKY. 



1. The method described by Tatum 1 was used to determine 

 the ratio of the percentage of iodine in cells to the percentage of 

 iodine in whole gland in the thyroid glands of normal and iodine- 

 fed dogs as well as in human thyroid glands obtained from opera- 

 tive cases. 



2. Evidence is presented indicating that the concentration of 

 intracellular iodine is independent of the suspending medium, 

 whether that is pure Ringer's solution, Ringer's solution containing 

 iodine-rich colloid material, or homologous blood serum. 



