262 INFECTIONS OF THE DIGESTIVE TRACT 



fore, to feed the animal so excessive a quantity of meat 

 that small masses of muscle fiber enter the lower ileum 

 or the large intestine. Here they will be attacked by 

 anaerobes and colon bacilli with a production of indol and 

 subsequent development of indicanuria. Naturally any 

 condition favoring stagnation in the small or large 

 intestine will help to bring about this condition. It is 

 possible that moderate quantities of hydrolyzed proteid 

 reach the lower part of the ileum owing to impaired 

 absorption. In this region both in man and in dogs the 

 colon bacilli are numerous. Under these circumstances 

 it is not necessary for anaerobes to take part in the attack 

 on the already hydrolyzed proteid, since, as repeatedly 

 stated, the colon bacillus itself suffices to do this. The 

 effect of introducing partially hydrolyzed proteids into 

 the large intestine was very plainly shown in the following 

 experiment. A healthy dog which had been fed on meat 

 in moderate quantities gave only a slight reaction for 

 indican. Fifty cubic centimeters of a concentrated egg 

 and meat mixture were subjected to short partial tryptic 

 digestion (without the development of indol). This 

 material was sterilized in the autoclave and then injected 

 into the transverse and ascending colon and confined 

 there by ligature. Two hours later the indican reaction in 

 the urine was markedly increased and at the end of ten 

 hours had become intense, this change doubtless having 

 been due to the bacterial attack to which the material 

 was subjected in the large intestine. 



There are some persons in whom the imperfect action 

 of a cathartic leads to the development of headache, 



