14 



Entomology and Zoology Department. [Bull. 168 



the common house mice are the guilty parties. If anyone is 

 skeptical on this point he has only to set a few small mouse 

 traps, properly baited, in the mole's runways and await re- 

 sults. In setting the trap a small excavation should be made 

 with a knife or trowel. Place the trap on a level with the bot- 

 tom of the runway. See that the latter is open both ways, and 

 cover the excavation with a board or piece of sod to exclude 

 the light and prevent the entrance of any small animal ex- 

 cept by way of the burrow. Try various baits, such as soaked 

 corn or peas, bits of meat, insects, and pieces of potato. 



With respect to damage to roots and tubers by eating into 

 them, it will usually be found on careful examination that the 

 tooth marks are those of rodents. 



Potatoes gnawed by rodents following in mole runways. Original. 



EXAMINATION OF STOMACH CONTENT. Direct evidence of 

 what an animal eats may usually be obtained in one or all of 

 three ways: By examination of stomach contents, by obser- 

 vations in the field, and by experiments with captives. In the 

 case of the mole field observations are of course impracticable. 

 By the other two methods, therefore, we have endeavored to 

 satisfy ourselves, and, we hope, others, as to the character of 

 a mole's diet. The accompanying table gives the results of the 

 careful examination of the stomach contents of 100 moles. 



