$4 FRIENDS WORTH KNOWING. 
the spring, that the mice have enjoyed good winter-quarters 
in his straw covering, and have been gnawing to death his 
choice roses. Millions of dollars, perhaps, would not pay 
for all the damage these small creatures thus accomplish 
each year in the United States, and I fear they will become 
more and more of a plague if we continue to kill off the 
harmless hawks, owls, butcher-birds, and snakes, which are 
the policemen appointed by Nature to look after the mice, 
and protect us against them. 
In captivity the wild mice, especially the white-footed 
Hesperomys, make very pretty pets; and one can easily 
study all their ways by giving them earth in which to bur- 
row, and the various sorts of food in which they delight. 
