THE MEADOW MOUSE 



81 



low the surface, it abandons its burrows and lives entirely above 

 ground. Its nests of diy grass then lie fiat upon the surface, with- 

 out attempt at concealment and are soon buried in the snow. As 

 winter advances and the snow becomes deeper, the ^Meadow "Mice 

 regularly betake themselves to their nests for rest. The heat from 

 their bodies soon melts the snow in contact with and immediately 

 adjoining the nests, which, from the continued operation of the 

 same cause, come to be surrounded by slowly-growing, dome-shaped 

 chambers. These increase in size until the spring thaws in March 

 aiid April, melt away their roofs, thus admitting the light and cold. 

 They are then deserted."'^ 



Fig. 20. — Map showing- locality records of — 



1. Meadow Mouse (Microtus pennsylvanicus pennsylvanicus). 



2. Prairie Meadow Mouse (Microtus ochrogaster ochrogaster) . 



3. Woodland Vole (Microtus pinetorum nemoralis). 



This form has been included in the earliest lists of Iowa rodents 

 and is one of the most abundant species of the group. It is found 

 in practically every locality in the state. Specimens are at hand 

 from the following places: Melvin, Thayer, Atlantic, Jefferson, 

 Waukoi), Charles City, and Iowa City. It has also been recorded 

 from Knoxville and Luxemburg. 



Food Habits, Economic Impoviance and Control Measures. — In 

 siunmer the food of the meadow mouse consists mainly of green 



"Merriam, C. H., Mammals Adirondack Region. 272, 18S6. 

 6 



