Genus Ondatra 



Rat-like animals, with robust form, tail long, thinly haired, 

 scaley, rather short legs, and large feet, toes of hind feet partly 

 webbed, fur waterproof. 



Fig. 5. Muskrat (Ondatra z. cirnaiiioiiiina) . From a specimen taken at 

 Ft. Collins, May 5th. Original. M. A. Palmer, delineator. 



Colorado Species of Muskrats. 



Rocky Mountain Muskrat, Ondatra zihetkica osoyoosensis. 



Great Plains Muskrat, Ondatra zihethica cinnamonima. 



The distribution of the two species in Colorado is in all the 

 plains region and the mountains to 10,000 feet elevation or higher. 

 The dividing line between the distribution of the two species in 

 the State may at this time be roughly given as the Medicine Bow 

 Range and the Great Continental Divide. Hundreds of specimens 

 must be examined, however, from all partsi of the State before 

 definite lines can be drawn. The meadow-mouse (Microtus sp.) 

 and the muskrats are closely related, although the latter is of much 

 greater size, the meadow-mouse measuring about 7 inches in length, 

 while the muskrat measures about 22 inches. Muskrats form one 

 of our greatest sources of small skins for fur. 



The London sale one year exceeded 5,000,000 pelts. Muskrats 

 build dome-shaped houses composed of roots, grasses, rushes and 

 other plants upon which they feed. I observed a muskrat one 

 fall that was busy carrying corn stalks from a corn field which was 

 alongside of a slough that was some three or four feet lower than 

 the corn field. The bank was sloping and the muskrat would climb 



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