YEAST PLANT. 97 



the bacteria termo, the excretory products are very complex, 

 consisting of ammonia, sulphuretted hydrogen, and other ill- 

 smelling products of putrefactive fermentation. Some of the 

 mucidines excrete butyric acid; other forms excrete other 

 waste products. Only a few of these have, as yet, been very 

 accurately studied. 



Often, perhaps, it is by these excretory products from bacte- 

 ria that gain access to the blood, and are capable of living 

 there, that disease is produced. One case in point. Dr. Car- 

 ter, of India, in his very careful and laborious examination 

 of the blood spirillum of relapsing fever, has found that these 

 organisms become still, and diminish in number during the 

 exacerbation of the fever, and during the intervals of com- 

 parative freedom from the rigor of the disease they become 

 active and augment in numbers, until the approach of another 

 attack of fever. What does this mean? Certainly the 

 disease is not caused in this case by the primary digestion, by 

 the soluble ferment, as it seems to be in hospital gangrene. 



The case seems reversed. Here it seems that the accumu- 

 lation of the excretory products of the organisms cause the 

 sickness ; also, that the amount present in the blood is suffi- 

 cient to check the development of the organism. Suppose the 

 yeast plant could grow in the blood, and develop its alcohol, 

 might it not intoxicate the man ? 



The course seems to be this. The soluble ferment excreted 

 by the spirillum affects the patient but little, the development 

 proceeds, and excretory products begin to accumulate more 

 rapidly than they are carried away by the emunctories ; finally, 

 when a certain concentration has been reached, the patient is 

 thrown into violent fever. The bacteria are also so affected 

 by their own excreta that they droop and fail to flourish. 

 They become quiet. The patient eliminates the poison, and 

 all is well again with both patient and spirillum, and the 



