ity, which is Twin or Lillie's peak, near Long's peak, at 9,000 feet, and 

 from North Boulder creek, also at about 9,000 feet elevation. The type 

 was taken in a perfectly dry locality covered by forest, most of which 

 had fallen. 



MUSKRATS. 



The Muskrat is well adapted to the semiaquatic life which it leads, 

 having a dense close under fur with long guard hairs which it is almost 

 impossible to wet through, at least while the animal is alive, an almost 

 naked tail flattened vertically, and large webbed hind feet set obliquely 

 to the leg so that they can be turned edgewise when carried forward. The 

 ears are small and hidden in the fur. It makes its home in holes in the 

 banks of streams and ponds, and houses of mud and grass are also built 

 in shallow water. Even though it is extensively trapped for its fur it is 

 still abundant, and is almost as much so in closely settled regions as in 

 the wilderness. At least civilization seems to have no terrors for it, and 

 the proximity of mankind does not drive the animal away. (After I had 

 written the preceding I learned that in Minnesota and elsewhere the catch 

 of Muskrats had decreased greatly the last year, the decrease being ap- 

 parently due to overtrapping during the period of extraordinarily high 

 prices for furs.) The food is grass and other vegetation; we often see 

 on the waters of ponds floating grass which these animals have cut for 

 lood. Where fresh water mussels occur these are brought up from the 

 bottom and opened by biting the hinge between the two valves, whereupon 

 the contents are devoured. 



While more or less of nocturnal or twilight habits the Muskrat is 

 often seen about in the daytime, especially when not much disturbed, 

 sometimes swimming or feeding, or sunning itself in some convenient 

 place. Trails are often worn through the grass where the animals come 

 up from the water or travel across from one water to another. The litters 

 are large, up to twelve in number, and are born from May to July, and 

 probably at least two litters in a season are the rule in Colorado. 



Two species are found in Colorado, the Rocky Mountain Muskrat, 

 Ondatra zibcthicus osoyooensis, which is the Muskrat found west of the 

 summit of the continental divide and the Sangre de Cristo Range; and 

 the Great Plains Muskrat, O. z. cinnnmominus, the species of the plains 

 region, but ranging up the eastern slopes of the mountains as high as 

 Ward, Boulder County. The summits of the ranges appear to form the 

 barrier between this and the Rocky Mountain Muskrat. 



POCKET MICE. 



The daintiest little animals we have are the smaller species of Pocket 

 Mice, the bodies of some of which are hardly as large and long as two 

 joints of one's finger, and which are clothed in a soft, silky fur. Unfortu- 

 nately one seldom sees them in life as they are practically exclusively 

 nocturnal. They have cheek pouches, or pockets with external openings, 

 hence their name, these pouches being used for carrying food. These mice 

 make their homes in burrows as tiny as their occupants, often about 

 yuccas o'r among low bushes, and sometimes with little trails leading from 

 one to another. The entrances are often closed during the day. Not all 

 these mice make small burrows, for the large Kansas Pocket Mouse makes 

 a good-sized hole, often going straight down into the ground. The food 

 consists -of the seeds of any of the plants occurring in their habitat. 



Pocket Mice are nocturnal in their habits. Some of the species are 

 among our very smallest mammals. Our smaller species vary in total 

 length from 4.5 to 5.5 inches, the tail being from 2 to 2.65 inches. The 

 Kansas Pocket Mouse has a total length of 8.75 inches, and tail 4.25 



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