1 50 Society for Experimental Biology and Medicine. 



Not only is this true for diphtheria and tetanus but it is likewise 

 true for the toxin produced from B. Botulinus and also for colloidal 

 ferric hydrate. In the case of colloidal ferric hydrate, by removing 

 the nerves and cord, and subjecting them to treatment with a solu- 

 tion of hydrogen sulphide, I was able to detect the presence of 

 iron. By using small doses I was able to show the presence of 

 these colloids in the nerves near the points of injection and in the 

 spinal cord, but of none whatever in the other tissues, except at 

 the points of inoculation. 



Guillian has demonstrated practically the same phenomena by 

 injecting a solution of ferric chloride into the sciatic nerves of 

 dogs and rabbits, and later injecting into the general circulation 

 potassium ferrocyanide. He found prussian blue only in the 

 part of the nerve above the point of injection. He also injected 

 india ink into the sciatic nerves of these animals, and in these cases 

 he could find no limit of ascension, but the particles showed for only 

 a short distance below the point of injection. He came to the con- 

 clusion that these substances travel by way of the lymphatics. As 

 a result of this work I have drawn the conclusion that tetanus 

 toxin does not travel by way of the axis cylinder, by any specific 

 attraction of the nerve tissue for this toxin, but it passes up because 

 the lymphatic flow of the nerve is passing constantly from the 

 periphery to the center. It is for this reason that the toxin when 

 injected subcutaneously or intramuscularly is taken up by the 

 nerves and passes to the cord, and the first symptom to develop is 

 the local tetanus, because these are the first cells that come in 

 contact with the toxin. 



It is a well known fact that in giving diphtheria or tetanus toxin 

 intravenously a much greater dose is required to cause death than 

 when either is injected subcutaneously or intramuscularly. The 

 reasons for this are first, that the toxin injected into the blood may 

 be combined with some of the blood elements and therefore ren- 

 dered inactive ; second, that by injection into the blood, the toxin 

 is diluted to a very great extent, whereas when injected subcuta- 

 neously, a portion passes into the lymphatics of the nerves and is 

 not mixed with the general body fluids, before it has reached the 

 central nervous system. 



Cernovodeanu and Henri have recently published the results 



