212 Roosevelt Wild Life Bulletin 



that was 37 feet in its greatest diameter. An old house in a drained 

 pond in Colorado, which I opened for examination, was 8 feet 

 wide across the section, and 10 feet the other way (figure 62). The 

 chamber was 2 feet wide, and extended back 4.5 feet. It was a foot 

 high, but I suspect that the roof had settled. It was furnished with 

 a bed of swamp grass. Dugmore gives the dimensions of one 

 chamber as follows: 4 feet 10 inches long, four feet five inches 

 wide, 2 feet 1 inch high, lower floor 4 inches above water, bed floor 

 6 inches higher. 



Bank lodges are of two kinds, probably with intermediate stages 

 between them. One sort is built against the bank, or with at least 

 part of the structure projecting into the water, really a burrow 

 extended and roofed over. The other kind is wholly within the 

 bank, connected with the water by a burrow, and is simply a burrow 

 enlarged and covered. A new one and an old one of this latter type 

 were seen on Carnelian Creek. The former (figure 63) was 4 

 feet back from the stream bank, 15 inches above ground level, 

 and 3 feet in diameter. An example of the first kind may be 

 seen near Camp Roosevelt, below the Cooke City road, and the one 

 in a pond a little lower down (figure 64) may possibly belong here. 

 This last is the one which v/as occupied by a family of beavers in 

 the summer of 1921. 



Burrows. Besides a lodge a beaver colony always has one or 

 more burrows in the banks of a pond as additional refuges. One of 

 these on the North Fork of Elk Creek was 31 feet long, which is 

 probably unusual, the majority no doubt being much shorter. One 

 sometimes sees piles of logs and sticks in the water over the entrances 

 to holes. These may in time develop into lodges. In Tower Creek 

 I concluded that beaver were living in a log jam where there was a 

 mass of debris high enough and solid enough to afford shelter for 

 one or more of the animals, and no other place v/as found where they 

 might be living. Also at another place on the same stream there was 

 beside the bank a somewhat confused mass of sticks and logs which 

 likewise appeared to be used as a dwelling. The creatures are 

 undoubtedly very adaptable in their choice of dwelling places. 



Canals. I am somewhat disposed to the belief that in some 

 respects the canal is a higher engineering achievement than the dam. 

 To deliberately plan and dig a channel in which to float logs to a 

 pond, and not only that, but also to build dams in this channel to 

 hold the water to a desired level, is an intelligent act. This is what 



