Influence of Radium on Frog's Leucocytes. 297 



normal blood showed 1 eosin., I poly., 98 lympho.: 24 hours after 

 radiumization, 2 eosin., 34 poly., 64 lympho., and 72 hours after 

 radiumization 1 eosin., 85 poly., 13 lympho. 



Radiumization of Yeasted Frogs. — The experiments consisted 

 in the injection of an emulsion of yeast into a normal frog, and 

 this was followed 24 hours iater by x-raying the animal or an in- 

 sertion of a radium emanation capillary. The injection of yeast 

 is followed by a change in the blood of a frog similar to the one 

 induced by the x-rays or radium, and the change is most marked 

 24 hours after the injection and continues for a few days. For 

 instance, the normal blood showed o eosin., 18 poly., 82 lympho. 

 23 hours after yeasting, 1 eosin., 73 poly., 26 lympho. Now the 

 remarkable phenomenon observed in this series consisted in the 

 fact that neither the x-rays nor the radium produced any further 

 noticeable change in the numerical relationship between the 

 lymphocytes and the polymorphonuclear leucocytes, or at the 

 most a very slight additional decrease of lymphocytes. To cite 

 an instance: the normal blood showed 2 eosin., 22 poly., 76 lym- 

 pho.: 17 hours after yeasting, o eosin., 60 poly., 49 lympho. The 

 animal was then x-rayed and immediately after showed 3 eosin., 

 68 poly., 29 lympho.: 24 hours later, 1 eosin., 80 poly., 19 lympho. 



The analysis of the experiments shows that in the frog, as in 

 the human, the action of the rays consists mainly in the diminu- 

 tion of the relative number of lymphocytes. However in the 

 normal frog it does not seem to be accompanied by a noticeable 

 change in the total blood count. The radiations seem to pro- 

 duce a different effect on lymphocytes of a normal frog from the 

 one produced on the lymphocytes of a yeasted frog. This phe- 

 nomenon is also analogous to effects which are related in the be- 

 ginning of the paper as occurring in the human. 



