MEADOW MICE, LEMMINGS AND MUSKRATS 
(Sub-Family Microtine) 
Cooper’s Lemming Mouse 
Synaptomys cooperi Baird 
Length. 4.80 inches. 
Description. Upper front teeth grooved, tail very short (.70 inch). 
Colour sepia brown, with many black hairs interspersed, 
some individuals with a slight admixture of buff or reddish- 
brown hairs, others somewhat grayer. Below plumbeous, 
generally with whitish tips to the hair, ears very short, 
overtopped by the hair, mamme six. 
Range. Southern New England and Michigan to Indiana and 
Virginia and in the mountains to North Carolina. 
In external appearance the lemming mouse bears such a close 
resemblance to the common field or meadow mouse, with which 
it frequently associates, that it would readily be passed by. 
Without considering its minute anatomy it will be sufficient to 
call attention to its grooved front teeth by which it can always 
be recognized, its rather coarser hair and very short tail, The 
lemming mouse was first described by Professor Baird in 1857 and 
for years after its discovery it was regarded as excessively rare. 
Modern methods of trapping, however, have brought to light 
many specimens and we have learned that it is pretty generally 
distributed throughout our Northern States wherever conditions 
suitable for its requirements are to be found. 
In connection with its rediscovery in our Eastern States it 
is interesting to know that science is indebted to that inde- 
fatigable mouse hunter, the barn owl, for the knowledge of the 
occurrence of the lemming mouse in several localities, the skulls 
having been found in the pellets of hair and bones which the 
owls had ejected about their nests. 
Cold sphagnum bogs seem to be the favourite haunts of these 
little animals in the East, where they use the ample runways of 
the meadow mice which form an intricate network of passages 
beneath the damp moss and among the roots of the grass and 
rushes. In winter the sphagnum freezes up, forming a solid 
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