CHORD. VIA 389 



there are several species in the United States, where the large 

 fox squirrels are also numerous. There is a very pretty little 

 species of flying squirrel in North America, Sciuropterus 10I11- 

 cellciy with a body about fifteen centimeters in length and a broad, 

 flattened tail equally long, and with folds of the skin between its 

 anterior and posterior appendages. Very different in general 

 appearance is the huge flying squirrel of Asia with its cylin- 

 drical tail, the body and the tail being each about sixty centi- 

 meters long. A similar squirrel lives in Africa (Fig. 379). 



Suborder 2. Myomorpha 



The Myomorpha (Gr. /aus, a mouse, and /xop<f)?j, form ), rat- or 

 mouse-like rodents, are mostly small animals. Some of the curi- 

 ous African species have the hind legs greatly developed, as in 

 the kangaroo, and use them for taking enormous leaps ; the 

 largest of these is the so-called jumping hare of South Africa, 

 about as large as a hare ; the jerboas found in other parts of 

 Africa resemble them except in size — they are only from fifteen 

 to eighteen centimeters long. Very different in habits are the 

 burrowing gophers, which are abundant in certain regions in 

 North and Central America ; they live almost entirely under- 

 ground. The average size is about that of the house rat, but 

 some are larger and others smaller. The pouched gopher of 

 the Mississippi Valley is a great pest to the farmers. The 

 muskrat is one of the largest members of this suborder. It 

 inhabits North America and has a handsome fur, which has 

 a considerable commercial value. The lemmings, which inhabit 

 the arctic regions of the northern hemisphere, are interesting 

 because of the migrations which they make in large numbers. 



The genus Mus, with scaly tail, includes about a hundred 

 species, and amongst them all the common rats and mice. Here 

 belong the common brown rat, Mus decumanus, an omnivorous 

 beast, and the common house mouse, Mus musculus ; some of 

 the other species are known by such popular names as wood 

 mouse, field mouse, deer mouse, golden mouse, mole mouse, 

 rice field mouse. Resembling some of these are the voles of 

 Europe, placed in another genus. The wood rats of the United 

 States also belong to another genus ; one species living in the 



