742 



Life-histories of Northern Animals 



without serious cramping. All their doors are 2 by 4 feet, and 

 open on the central alley. Their sill sides should be raised a 

 foot to allow for snow. 



In each, at its driest point, a hole about 3 feet wide 

 and 2 feet deep should be dug and roofed over with some- 



Fig. 197 — A model Fox-yard. Scale 50 feet to one inch. 



thing to turn the rain. A 9-inch hole, angling down to this 

 at one side, completes the den. In the Norton yards 

 these dens were shingled, as it is very important to have 

 the nursery well-drained and dry. No lining is needed. The 

 mother Fox can add it at will, or leave it out, as she mostly 

 does. 



The large cages are loose ranges for any or all that are not 

 nursing mothers or very young. All open into the central 

 lane, as an additional safeguard against escape. This lane 

 is 4 feet wide. It is furnished with a movable alley-cage about 

 5 J feet long by 2 feet wide and 4 high; it is made on the bias 

 and provided with a drop door at each end. Both top and 

 bottom should be of light boards, as sometimes one is floor, 



