52 Zoology of Colorado 



at Lake Moraine, El Paso County and near Buffalo Park, Jackson 

 County; it is a grayish brown mouse five and one-half inches 

 long. It was formerly recorded as P. orophilus. P. preblei of 

 Merriam, a yellower animal, has been found near Long's Peak 

 and on North Boulder Creek.* Our only Evotomys is E. gapperi 

 galei, discovered by Denis Gale,** at Ward, and named in 1890 

 by Merriam. It is known by the chestnut area down the back. 

 We have five kinds of Microtus in Colorado, belonging to three 

 different subgenera.*** The introduced Murinae include the 

 house mouse (Mus musculus of Linnaeus)**** and the Norway rat 

 (Rattus norvegicus of Erxleben). Both are great pests in towns, 

 spreading rapidly over the State since their introduction. Melan- 

 ic specimens of the Norway rat, taken in Boulder, simulate the 

 black rat, which does not occur in this region. This variety is 

 the Rattus norvegicus var hybridus, named by Bechstein in 1800. 

 R. norvegicus var, albinus is the albino form.***** Morgan de- 

 scribed a wild variety of Mus musculus taken in Colorado, peculiar 

 for its fulvous color; it was perhaps the form named flavescens by 

 Fischer in 1872, but it also resembles somewhat the form azoricus 

 of Schinz, which Miller regards as a subspecies, 



The Dipodoidea include in our fauna the Zapodidae, the 

 jumping mice. They have small internal cheek pouches, long 

 hind limbs adapted for jumping, tail very long, upper incisor 

 teeth grooved. Our species belong to the genus Zapus of Coues; 

 the larger and darker one is Z. princeps of Allen; the smaller and 

 paler Z. hudsonius campestris of Preble. Z. princeps is widely 

 distributed, and campestris has been found in Larimer, Weld, 

 Arapahoe, Jefferson, and Boulder Counties. These mice are 

 small, but owing to the very long tail, the total length is con- 

 siderable; eight and three-quarter inches in campestris, nine and 



*A. B. Howell (1926) considers that P. preblei is not to be separated from P. intermedins. 



**See Henderson, An Early Colorado Naturalist, Denis Gale: Univ. of Colo. Studies, V. 

 No. I, (1907). Gale was born in London in 1828, and died in Denver, 1905. His work in 

 Colorado began in 1883. His note books, and his collection of nests and eggs, are in the 

 University of Colorado Museum. 



***For details see Bailey, North American Fauna, No. 17. (1900), and Warren's Mam- 

 mals of Colorado (1910). 



****"Inhatit8 houses and granaries in Europe, Asia and America; follows mankind; eats 

 all kinds of provisions, drinks little; gentle, timid, quick, prolific; devoured by rats, cats, weasels, 

 owls, and hedgehogs; destroyed by elder and hellebore; about 3J-^ inches long; varies much in 

 color, is said to possess a small electric property when alive." Turtcn's edition of Linne System 

 of Nature, (1806). 



*****See Journ. Comp. Neurology, 22 (1912); p. 71 ; Amer. Journ. Anatomy, 15 (1913) 

 p. 87. 



