THE MOUSE AND RAT FAMILY 401 
reduced by the diligent use of traps. A good cat or dog will 
often clear the place of them in a short time. 
The Muskrat is the largest American member of the mouse 
and rat family and is distributed over a large part of the con- 
tinent as far south as Mexico. They live in ponds and streams 
and are good swimmers and divers. They show much in- 
dustry and intelligence in building their houses. These are 
constructed in shallow water out of coarse grass, weeds, and 
mud, and rise several feet above the surface. The living apart- 
ment within is located above the level of the water, but is 
entered from beneath, so that ice cannot close the entrance 
in winter. Muskrats inhabiting streams with high banks do 
not build these houses but merely burrow into the banks. 
Muskrats are among our commonest fur-bearing animals, 
and trappers catch large numbers of them, every year. In 
some sections of the country muskrat farming has proved a 
profitable industry, and we have many suitable lakes and 
sloughs that might be devoted to the purpose. 
