Burro-vs of the American Marmot. in 



on a level to a point p, distant from e about six feet, six 

 inches, and then ascending terminated in the entrance or exit 

 C. Just south of the intersection of this branch with the 

 main runway, a large nest was present, twenty-four inches 

 across from east to west, and fourteen inches from north to 

 south. The peculiarity of this nest was that it was not a 

 mere enlargement of a semicircular description on the side 

 of a runway, but it constituted a distinct chamber connected 

 with the enlarged area at the intersection of the main runway 

 and the branch leading to C, by a distinct, short, narrow run- 

 way. Thus great privacy could be maintained in this chamber, 

 and at the same time the occupant or occupants could be 

 cognizant of any living thing which passed through the main 

 runway, or the branch thereof from e to C. To return to the 

 main runway. This extended from the enlarged intersection 

 in a south-westerly direction to g, and at the same time grad- 

 ually descending. Here its bottom was thirty-six inches 

 below the surface of the ground, the latter also gradually 

 ascending to this point. From g, the ground surface grad- 

 ually descended to the entrance B, and the runway gradually 

 ascended. The direction of the runway from point g changed ' 

 to a direction east of south. 



It will be observed that the ne.st is located on a level with 

 the bottom between e and f, and, therefore, is elevated so 

 that moisture in the main runway will seek the points C or g, 

 and will not reach the nest. This is not true of the branch 

 runway to any extent. One other interesting feature consists 

 of a great mound of earth cast up at and south of the entrance 

 B. This mound was four feet, nine inches from east to west, 

 and four feet from north to south. The highest point of the 

 mound was nine and a half inches above the general level of 

 the ground about it. It was covered with grass, except the 

 central portion, and a path from there to entrance B. This 

 path was below the general level of the mound. These facts 

 would indicate that the mound w^as formed by the earth taken 

 from the runway, and that its elevation was made use of as 

 the nearest post of observation, close at hand to the burrow. 



EXCAVATION D. 



Part of the clover patch hereinbefore mentioned was on the 

 same level as the land in which the burrow laid bare by exca- 



