IOWA ACADEMY OF SCIENCES. 



273 



owing to the destruction by fire of all of our cultures. We 

 found present in the milk a large number of chromogenes, 

 but none of these, of course, can be referred to, or are in 

 any way related to the typhoid fever bacillus. On the 

 other hand, we did find B. coli-comntunis, but it does not 

 necessarily follow that the B. coli-coitiviKuis comes from 

 human dejecta, as this organism is very commonly found 

 in connection with cow stables, and the organism being 

 found quite frequently in the intestinal tract of animals as 

 well as man. Therefore this cannot be considered to be 

 the cause, nor as an argument against the use of milk. 

 This work, however, was not completed, and hence a final 

 statement cannot be made. 



COMPARISON WITH THE SEWAGE BACTERIA. 



The results of the work carried on on the College Sew- 

 age Plant show the following conditions with reference to 

 the purification, and it is of interest to compare these 

 results with the water obtained from the Briley well. It 

 will be seen that in every case, excepting the last one, that 

 the Briley well contained many times more organisms 

 than the effluent of either filter bed. 



