THE MUSKRAT 97 



attention to a series of seven Mnskrat skins from Hayfield, Iowa, 

 all of which were uniformly marked, having- a white ring around 

 the neck and the entire under parts, feet and terminal portion of 

 the tail white. Such uniform coloration in a series of specimens 

 was perplexing and suggestive especially as they all came from the 

 same locality; but later two specimens were received from Indiana, 

 which were similarly marked, but with the dark parts much paler. 

 The Field Museum collection contains a pure white example of this 

 species."-" A specimen collected November 2, 1914, at Sabula, 

 Iowa, and sent in to the University Taxidermist's laboratory is a 

 uniform rusty white. 



Habits, Distribution, Etc. — The muskrat or musquash, as it is 

 sometimes called, derives its nam.e from the peculiar musky odor 

 which is given off by the animal. Its favorite haunts are in ponds, 

 streams, and overflowed marshes ; and it is found in practically 

 every part of the state where such situations occur. It lives partly 

 on land, and possesses also characters which adapt it for living 

 in the water. The hind feet are slightly webbed, and are formed 

 so that they may be turned edgewise when moved forward while 

 the animal is swimming, thus affording the least possible resist- 

 ance to the water. The long flattened tail acts as a rudder in 

 swimming; the fur is long and glossy, and the underfur is very 

 dense, thus making practically a waterproof covering. 



Muskrats sometimes wander a considerable distance from water, 

 particularly in late fall, early spring, and during severe droughts. 

 The spring migration has been thought to be due to sexual excite- 

 ment, but no definite reasons can be assigned for the movements 

 at other time^5. 



While muskrats are, for the most part, abroad at night, they 

 are often seen in daytime swimming about, lying in the sun along 

 a bank, or working on their winter houses. 



Muskrat houses are' composed of grasses, roots and stems of 

 aquatic plants, rushes, weeds, etc., and the writer has seen entire 

 houses constructed almost wholly of mud and cornstalks. Appar- 

 ently the animals utilize the material closest at hand, and that 

 which, at the same time, will serve the purpose reciuired. These 

 houses rest upon the bottom of the pond or stream, the domelike 

 top composed of disarranged materials rising from one and one- 



"'Cory. Charles B., Mamimals of Illinois and Wisconsin : Pub. Field Mus. 

 Nat. Hist., Zool. Sen, XI, 226, 1912. 



