41 
poison in the same sense that Behring and Kitashima showed in 
guinea pigs treated with small doses of diphtheria toxine. These 
investigations terminated negatively. The authors succeeded, how- 
ever/in inducing hypersusceptibility to tetanus toxine in rabbits by 
the intradural injection of minute amounts. 
From the above review it seems to have been definitely shown 
that the motor nerves have a specific affinity for tetanus toxine. 
When the toxine is given subcutaneously^ the adjacent motor nerve- 
endings at once begin to take it up and transport it to the cord. The 
lymphatics also absorb much of it, and in a short while it appears in 
the blood stream, which carries it to all parts of the body, where it 
is absorbed by the motor nerve-endings, which are bathed in the 
toxine-laden fluid. The reason that the symptoms appear earlier 
in the limbs in which the toxine is injected is because the toxine-index, 
as it were, is higher there than in other parts of the body. When 
the toxine is given into the cord or into a nerve trunk, the incubation 
period is shortened; if into a nerve trunk, the tetanus is sharply 
localized at first, and in fact the animal may die before general tetanus 
sets in. When given into the circulation, generalized tetanus results 
in a short time. The weight of evidence is in favor of the view that 
the toxine produces its effect solely by the absorption of the toxine 
by the nerves, whose axis cylinder substance has a specific affinity 
for the poison. They transport it to the cord and brain through the 
axis cylinder substance itself. 
THE GERMAN METHOD OF STANDARDIZING TETANUS ANTITOXIN.fi 
The official testing of this serum is conducted at the Kgl. Institut 
fur experimentelle Therapie zu Frankfurt a. M., of which Dr. Paul 
Ehrlich is the director. Tetanus antitoxine, like other curative sera, 
is examined in the Institut first for harmlessness and second for 
potency. 
The serum is considered harmless if (1) it is wholly clear and free 
from much precipitate; (2) contains no bacterial contamination; (3) 
contains not more than 0.5 per cent phenol or 0.4 per cent trikresol; 
(4) is free from toxines, especially tetanus toxine. 
The serum should not contain more than a very slight precipitate 
at the bottom and must under all circumstances be absolutely clear. 
The tests of the serum for sterility are made in accordance with the 
usual bacteriological methods. Five drops of the serum are planted 
into one agar plate, two glucose-bouillon test tubes, and a glucose- 
agar test tube with a sufficient quantity of the media for deep anse- 
The account of the German methods of testing is taken from Otto’s work entitled 
“Die Staatliche Priifung der Heilsera,” Jena, 1906. Also from Behring’s “Die 
Wertbestimmung des Tetanus-antitoxins und seine Verwendung in der Menschen- 
arztlichen und thierarztlichen Praxis,” Deut. med. Woch., vol. 26, 1900, p. 29-52, etc. 
