THE ALIMENTARY CANAL AS A SOURCE OF CONTAGION 35 



in the intestinal contents or introduced on occasion, whether, in fact, such 

 a blood-destroying organism, or several of such organisms, is constantly 

 present in the alimentary canal, and prevented from exerting its 

 injurious influence on the blood by the interposition of the intestinal 

 wall. Indeed it comes to be a question whether specific anaemic diseases 

 should not be regarded as functional disorders of the intestine rather 

 than, primarily, diseases of the blood. 



We have seen that in chorea paralytica of the sheep the blood is free 

 from organismal impurity while the intestinal contents are permeated 

 with a highly contagious anaerobe, yet there is evidently some toxine 

 circulating with the blood which stimulates and subsequently paralyses 

 the motor nerve cells. The explanation I have given of the pathology 

 of these phenomena, and the theory is founded on fairly conclusive 

 experiment, is that a certain proportion of the bacteria which are the 

 cause of the disease, and which are resident in the intestine, get into the 

 blood-current and are bacteriolysed. The liberated toxines afterwards 

 coming in contact with the nerve cells induce the characteristic 

 phenomena of the disease. 



May it not be that allied bacteria, of anaerobic habit and with 

 haemolysing tendencies, similarly, in certain morbid conditions of the 

 intestine, manage to pass through the barrier constituted by its wall, 

 become bacteriolysed in the blood-current, have their haemolysing 

 poisons liberated, and that such again come to act on the blood- 

 corpuscles, either simply depriving them of their haemoglobin as in certain 

 of the chlorotic varieties of anaemia, or, in addition to this, effecting a 

 solution of the whole corpuscle as in the pernicious varieties of the 

 disease ? 



Tetanus. 



We have seen that certain instances of chorea paralytica have quite 

 a tetanic character, and that apparently Tetanus can be aroused in the 

 sheep by injecting subcutaneously the bacteriolysed organism of the 

 disease. 



The organism of Tetanus has a very close relationship to that of 

 Louping-ill, indeed to all the members of the group, and, manifestly in 

 their all being anaerobes, in their tendency to sporulation, and when 

 sporing, in the readiness with which they assume the drumstick con- 



(35) D ' 



