60 THE ROYAL SOCIETY OF CANADA 



at 5.50 p.m. on the 9th day and others suspected on the morning of the 10th and 

 afternoon of the 11th day. The animal subsequently appeared normal. 



Rat 9 was found dead on the morning of the 16th day of treatment. Tetany 

 was suspected. 



Rat 10 had an attack of tetany on the morning of the 15th day of treatment 

 with rapid heart beat and convulsions. It did not eat the thyroid dose on this 

 day. 



The animals which survived till autopsy showed bright-red thyroids in every 

 case. Rat 7 showed no fat deposits; the others seemed normal in this respect. 



The results, as far as body-growth is concerned, are shown for 

 all rats which survived till autopsy in Table I. Those rats which 

 died during treatment, with the exception of control 2 in experiment 

 6, showed no abnormal growth change when compared with those 

 similarly treated. The weights of body-organs, calculated to per- 

 centage of total body-weight, are shown in Table II. 



