546 



Life-histories of Northern Animals 



DEN The diagram in Fig. 156 represents a Muskrat's home 



that I examined at Cos Cob, Conn., in July, 1905. It was 

 under a clump of young ash trees and presents all the usual 

 characteristics of the bank dens. Nos. 2 and 3 were holes at 

 water level. They were plugged up with grass and sticks as 

 when exposed by the water lowering; i, the real entrance, was 

 deep under water and was made later; 5 was a den with about 



II in 



(1 





Fig. 157 — Section of the simplest style of den made by Muskrat, Cos Cob, Conn., igo6. 



2 inches of water in it, 6, a small den not connected with the 

 others; 7, a small den at a lower level than the main den; at 

 9 is a plunge hole from the den into deep water; 8 was the main 

 den, nearly round, 15 inches each way, smoothed with great 

 labour in gnawing off thick roots. It was very near the surface 

 and had a ventilator under the stick pile, as also had 6. 

 The pathways were evidently made by the Muskrats in carry- 

 ing up these sticks. 



The main den had quantities of green grass and stalks in 

 the corners; among these jewel-weed was prominent. This 

 was fresh cut, and may have been either food or bedding, 

 probably both. 



This den illustrates the style of all those I have examined 

 on banks. They have one main entrance under water, some- 

 times other smaller entrances. The tunnel leads up to a com- 

 modious den, which is open to the air at one small place, and 

 covered outside with a pile of sticks and grass. 



