386 



Life-histories of Northern Animals 



NESTING 



At Whitewater on April 29, 1904, I examined the nest and 

 burrow of a Yellow Ground-squirrel. This one was selected 

 because I saw an old one run into it with a mouthful of grass. 

 After four hours of hard work by myself and my assistant, E. 



iclbiock W. Darbey, we dug 



out and made care- 

 ful measurement of 

 the labyrinth, plans 

 of which are given in 

 Fig. 120. We did not 

 see anything more of 

 the owner, so doubt- 

 less she escaped 

 by some passage to 

 another burrow, 

 probably plugging 

 the gallery behind 

 her, as we missed it. 

 This is the usual ex- 

 perience in digging 

 after a burrowing 

 animal. The grass 

 ' she was carrying 

 was found scattered 



Burrow of Richardson Ground-squirrel, Whitewater, alOUff the OUter Hal- 

 Manitoba, April 29, 1904. (Plan). ^ ° 



lery. 



The small room marked *'old den" had no connection 

 with the burrow, so far as we could learn. It may have been an 

 ancient chamber abandoned long ago, as it was full of hoar 

 frost and had no sign of occupancy. Two or three of the galler- 

 ies were too small for the Squirrel to have made and were prob- 

 ably the work of Mice. I am inclined to think that at least one 

 species of Mouse is a parasite or commensal of these Ground- 

 squirrels, inhabiting the small off-shoot galleries. These they 

 make from the tunnels of their host and, tapping the store rooms, 

 steal the provisions laid up by the larger rodent. In this case we 

 found a colony of Microtus drummondi not far from the burrow. 



