HOUSE MOUSE 



Measurements. — Total length, 6-6.5 inches; tail vertebree, 

 3.0-3.5 inches; hind foot, .70-.75 inch. 



Geographical Distribution. — Found almost everywhere in 

 United States and Canada where settlements or commerce 

 exist. 



Food. — Almost omnivorous, but preferring grain and 

 various vegetable products. 



Enemies. — Snakes, Hawks, Owls, Weasels, Foxes, and all 

 small carnivores; domestic Cats and Dogs. 



Species and Subspecies of the Genus Mus. 



Only the one species of this genus has established a foothold 

 in North America. In Alexico this Mouse has apparently 

 developed a distinct subspecies and it is possible that other 

 distinct races may appear in other places as this species 

 becomes a more integral part of our native fauna. 



The House Mouse is too well known to require any extended 

 remarks, but since it may be confused, under certain circum- 

 stances, with some of the native species of Mice, attention is 

 directed to some of its distinguishing traits. 



While this Mouse is more or less truly a "house" Mouse 

 about large cities, and where a severe winter climate forces it 

 to seek shelter, in many places it lives in the fields and waste 

 places and may be trapped side by side with native species. 

 From most of the common native Mice, Mus may be dis- 

 tinguished by the ashy underparts, dull color pattern, and long 

 semi-naked tail. Meadow Mice, with a somewhat similar 

 color pattern, have more robust bodies, longer, fuller pelage, 

 and generally a shorter tail. White-footed Mice need not be 

 confused with the House Mouse because of the much different 

 color pattern. The Harvest Mice bear the closest re- 

 semblance to House Mice, and although these native Mice 

 are usually smaller in size than an adult House Mouse, the 

 resemblance may be quite marked. Harvest Mice are more 

 slenderly built and have proportionally longer tails. An 

 infallible test may be applied if one has the skull of the Mouse 

 for examination. The molar teeth of the House Mouse, as 

 well as the molars of the three following species of introduced 

 Rats, have three longitudinal rows of tubercles along their 

 crowns, distinguishable at all stages of wear (in worn teeth 



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