214 The Story of the Bacteria 



destiny. The plate was covered and set in a 

 warm place for three days. Wherever his 

 feet touched the gelatin, and where the body 

 dragged, the bacteria grew. The result is 

 seen in Plate XIII. The track of the wander- 

 ing fly is marked in colonies of living bacteria, 

 many thousands in each. 



Similar results follow the contamination of 

 milk by dirty flies. So also foods which flies 

 visit and fresh berries in city markets are 

 planted with germs of varying potency. 



It is from improperly cared for discharges of 

 typhoid patients that the chief danger comes. 

 In the country the unsanitary out-houses 

 which disgrace the age and in the cities which 

 discharge their sewage into adjoining waters, 

 there is abundant opportunity for fatal con- 

 tamination of food through the fly. So 

 flagrant are the offences and so significant are 

 the results, especially in connection with 

 typhoid fever, that it has been suggested by a 

 distinguished entomologist that this fly known 

 to science as Musca domestica should hence- 

 forth be called the Typhoid fly. 



But I suppose that there is something to be 



