HALE AND SEIDELL: SUPRARENAL GLAND 



227 



From this table it will be seen that fairly large differences exist 

 in the two sets of values; however, it will be noted that a close par- 

 allelism exists between them. The results by the physiological 

 method are some 30 per cent higher in most cases. We are unable 

 at present to account for this but believe that the small amount 

 of yellowish extractive material yielded by the samples is the 

 cause of the lower readings by the colorimetric method. In spite 

 of these variations, however, this test appears to be by far the 

 most satisfactory one at present available and furnishes a means 

 for closely estimating the relative value of different lots of desic- 

 cated suprarenal glands and 1:1000 solutions of the active prin- 

 ciple. We hope to be able in the near future to extend our exper- 

 iments to man}^ other samples, both of the desiccated glands and 

 the commercial 1 to 1000 solutions and trust that we will be able 

 to remedy the cause of the present differences in values obtained 

 by the two methods. 



In conclusion special attention should be called to the very wide 

 differences in activity found for the various commercial samples 

 of desiccated glands and the considerable diminution in strength 

 of a 1 :1000 solution of the active principle. Such wide varia- 

 tions have not so far been reported for the commercial glands 

 and were not expected when we undertook these experiments. 

 They illustrate very forcibly the need of just such a simple met Ik id 

 of control of this product as is described in the present paper. 



