1936] MAMMALS OF OREGON 237 



wide open and very large. In the dark they shine with reflected 

 light as two glowing yellow balls just the color of the full moon 

 well above the horizon. 



In disposition the animals are surprisingly gentle and tame with 

 man and to a limited extent social and friendly with each other 

 in a family or colony. With others from different dens they are 

 savagely unfriendly. Seven were caught alive at one group of bur- 

 rows and kept in a two-room cabin. When put in a box together 

 they all fought like cats and dogs, but given the run of the house 

 they selected separate quarters in boxes, tin cans, boots, the stuffing 

 of a lounge, and in a corner of the wood box. They did much chas- 

 ing and fighting around the rooms at night and several were killed 

 by the others, but finally several became wonted to the wood box and 

 slept together or in different corners of it. 



Dens and burrows that were dug out and mapped were often found 

 to be elaborate and complicated. One large den in an old barren 

 field covered about 12 by 20 feet, with 4 main entrances where con- 

 siderable earth had been thrown out, but each entrance kept closed 

 during the day. Aji elaborate system of connected burrows led to 

 several nest and food chambers a foot to 1% feet below the surface, 

 and 10 blind burrows were traced to points near the surface where, 

 in case of danger, an animal might easily break through and escape. 

 Two main and five smaller storage chambers contained a little food 

 and food refuse. At least 2, and probably a family of 5 or 6 animals, 

 occupied this den. Other burrows examined were much simpler in 

 nature, some with only a single burrow with a main entrance and 

 blind exit and a small nest and food chamber at the bottom. Usually 

 the occupant escaped by breaking out through the back door and 

 making off at a flying pace to some other burrow. 



Climbing. Those in captivity have shown unexpected skill in 

 climbing, in running through branches of sagebrush in the wood 

 box and through the slender branches of large weeds and bushes, and 

 in balancing on edges of boxes and thin boards. They will hop to 

 the top of a 15-inch box, sit on the edge of the thin board, hop across 

 to the other edge, or to the edge of another box, swarm up a big 

 dry mustard plant and sit on the branches with tails pressed against 

 the branches or stems to keep a balance, climb to the tops of screen 

 doors and then jump down, and climb up a bed blanket that reaches 

 near the floor and find their way into bed in a friendly fashion. The 

 wild mustard plants, often 4 or 5 feet high, from which much of their 

 food is gathered, are evidently climbed as the small branches are cut 

 off and the seeds stored for food. 



Fighting. When two strangers meet there is sure to be trouble. 

 One will jump on the other, or both will sit up and spar with their 

 hands each trying to get hold of the other with its teeth. Sometimes 

 they will clinch and bite and kick each other until one breaks away 

 with a bloody nose or torn skin or broken tail and runs for its life, 

 with the other in hot pursuit. One was found dead in the morning 

 on the floor with its nose and tail bitten and dozens, of little holes 

 through the skin of the back and into the flesh, where the sharp toe 

 nails of the hind feed had been driven in with great force. Later 

 two other dead ones were found behind the wood box, torn and 



