x PREFACE 



individually taken part ; but it is a joint work, the result of the 

 principle, which animates the whole laboratory. It owes its 

 existence to the acuity of each individual, but in its totality to the 

 guiding conception which has inspired us all. 



When I look back upon what the laboratory has accomplished 

 in our field of research, I know well how much the work of every 

 individual is to be valued. I should, therefore, like to take this 

 opportunity of sending heartiest greetings, in the name of the 

 laboratory, to all our dear co-workers, who are widely scattered 

 over our native land, with the hope that they have preserved as 

 friendly recollections of us as we have of them. 



These lectures were first delivered before an audience of 

 medical men in the Institute for Experimental Medicine, and 

 later, in a shorter form, in the Military Medical Academy. All 

 the experiments which were demonstrated before both these 

 audiences have been included in the work. 



THE AUTHOE, 



ST. PETERSBURG, April 1897. 



