190 John Bruce MacCallum, M. D. 



7. The influence of calcium and barium on the flow of urine 

 is in every way analogous to their action on the intestine, which 

 I have previously described. The suppression of the urinary 

 secretion by calcium is also analogous to the suppression of twitch- 

 ings in voluntary muscles by calcium, which has been described 

 by Loeb. 



In conclusion it is a pleasure to thank Professor Loeb for the 

 interest which he has taken in these experiments. I am indebted 

 also to Dr. Theo. C. Burnett, who has assisted me in many of 

 the experiments. 



