TYPHUS MURIUM. 425 



portance. Agar-agar cultures are best, as being most 

 readily transportable. They are broken up in water and 

 well stirred, and the liquid poured upon a large num- 

 ber of small pieces of broken bread. These are next to 

 be distributed with reasonable care. Instead of being 

 carelessly scattered over the ground, they should be 

 dropped into the fresh mouse-holes, and pushed suffici- 

 ently far in to escape the effects of sunlight upon the 

 bacilli. Attention should be paid to holes in walls, 

 under railway tracks, etc. and other places where mice 

 live in greater freedom from disturbance than in the 

 fields. (3) The attempted eradication of the mice should 

 be begun at a time of year when the natural food is not 

 plenty. By observing these precautions the mice can be 

 eradicated with certainty, usually in a period of time not 

 exceeding eight to twelve days. For this purpose, in the 

 course of two years, no less than 250,000 cultures were 

 distributed from the Bacteriological Laboratory of the 

 Tierarznei Institut in Vienna. The bacilli are not 

 pathogenic for the animals, such as the fox, weasel, 

 ferret, etc. that feed upon the mice, do not affect man 

 in any way, and so seem to occupy a useful place in 

 agriculture by destroying the little but almost invincible 

 enemies of the grain. 



