MEADOW MICE, LEMMINGS AND MUSKRATS 



(Sub-Family Microtince) 

 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, mammae six. (Illustration facing p. 120.) 



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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