The Lemming Mouse: Cooper's Lemming Mouse 



Synaptomys Coo peri 



The lemming mouse is found in boggy regions at 

 a few places in the State. It often uses the runways of 

 meadow mice and is frequently caught with them. It 

 resembles the meadow mouse so closely that it is apt 

 to be mistaken for it. The lemming mouse may be 

 distinguished by its short tail and by its grooved front 

 teeth. The head is blunt; the ears are nearly hidden in 

 the fur, and the legs are short. Its coloration is vir- 

 tually the same as that of the meadow mouse and the 

 two sexes are alike. There is a slight seasonal varia- 

 tion, the summer color being a bufify gray or yellowish 

 brown lined with black, and the winter color being a 

 slaty gray. It is about five inches long when full grown. 



Red Backed Mouse: Red Backed Vole 



Evotomys (/apperi gapperi 



Although usually preferring forest haunts, the red 

 backed mouse is frequently to be found in grassy 

 fields where it hides under fallen logs or under stones. 

 It really lives in underground burrows similar to those 

 of field mice but usually selects dry, well-drained 

 ground. Its nest is made of fine dry grass or moss and 

 is placed within a chamber along one of its under- 

 ground tunnels. Sometimes it nests in a hollow log 

 and, on one occasion, I found a number of nests under 

 a slab of corrugated iran. Several litters of young are 

 born during the summer and each litter may contain 

 from three to eight young. 



The red backed mouse is related to the field mice, 

 but it seldom menaces crops as do the latter at times. 

 The distribution of this form in Pennsylvania is some- 



M. 133 ><*- 



