10 
BULLETIN 301, U. S. DEPARTMENT OF AGRICULTURE. 
The large den shown in figures 7 to 9 has advantages not found 
in barrel dens. It has double walls, the interspaces being lined with 
building paper and filled with sawdust. The exterior may be bat- 
tened, shingled, or covered with tarred paper. It is large enough 
to give the foxes lounging room outside the nest compartment, and 
is arranged so as to be easily cleaned and disinfected. By leaving 
the door open on fine days, the interior can be exposed to the drying 
and purifying effects of sunshine. The door and the opening to the 
exit chute should face southward, and the rear end should be raised 
enough to give the floor a slant downward toward the door. The 
B2094-96 
Fig. 5.— Vertical longitudinal section of barrel den. 
entrance to the nest compartment and the inner end of the chute 
should be about 4 inches above the floor to prevent the cubs' getting 
out before they are able to return. 
The corners around the floor of the nest compartment are filled 
with a chamfered strip of board (figs. 7 and 8) to keep very young 
cubs in contact with the vixen and thus prevent their becoming chilled. 
To accommodate a large family of cubs running about the yard, 
it is advisable to have extra dens improvised from barrels or boxes, 
as shown in figures 10 and 11. Such shelters increase the diversity 
of the yard, and afford the animals a choice when seeking protection 
from the weather. As to the proper location of a den, opinions differ. 
