No. 488] 



HABITS OF THE SHREW 



503 



only water and snails. In each case the one confined with snails 

 died in less than 48 hours, the other remained in uood condition. 

 From these experiments I have concluded that all linrrows with 

 snail shells in or beside them were at one time used In tlu> shrew. 

 Taking this as the only criterion at first, I found other features 

 later which distinguished the burrows of the two animal-. 



The burrows used by Blarina were usually iV) t.) ;5() nun. in diam- 

 eter. Those at the surface were exactly like tho.e of ^Microtus. 

 running in zigzag fashion imder weeds and grasses, often pushing 

 the latter aside, sometimes crushing them down, crossing and re- 



