ACTION ON ANIMALS 135 



extraction only. It must be understood that the poison 

 is not in a pure state and when it is stated that 60 mgs. 

 causes death when injected intraperitoneally we refer simply 

 to the powder obtained from a given extraction. We have 

 been able to procure powders which kill in doses of 15 and 

 even as low as 8 mgs. when given intraperitoneally. This 

 difference is in large amount due to the presence of sodium 

 chloride, since no attempt has been made to remove this 

 salt in the case of the less toxic powders by redissolving 

 in absolute alcohol. 



There are several facts which lead us to believe that 

 this poison is the one which causes the symptoms of illness 

 and death in animals infected with the colon germ. Most 

 of these facts have already been brought out, but it may 

 not be out of place to briefly recapitulate at this point. 

 As has been previously seen, the results obtained with the 

 living germ, the dead bacterial substance, and the soluble 

 poison can best be explained on the ground that the poi- 

 sonous body in each case is the same. The differences in 

 action are not differences in symptoms, but simply in the 

 rapidity with which these symptoms become manifest. 

 While it is undoubtedly true that in animals dying with 

 the minimum fatal dose of the living germ, the convulsive 

 stage is not present or is only slightly marked, it is rarely 

 absent in cases where from three to four times the fatal 

 amount has been given. The sole difference between the 

 living germ and the soluble poison which would appear to 

 demand an explanation is the lack of evidence of a perito- 

 nitis in the latter case. This, we think, is best explained by 

 the fact that in the case of the soluble poison the poisonous 

 substance exists in an uncombined form, which, of course, is 

 not true in the case of either the living or the dead bacte- 

 rial cell. The uncombined poison is rapidly absorbed from 

 the peritoneal cavity, and hence the irritative effects which 

 would result from its retention in this place are absent. 



As has been stated, one of the first signs of the action of 

 the poison is a lowering of the body temperature. This 

 hypothermia is usually present to a marked degree, and 

 is noticeable before any visible symptoms occur. It is, 



