]Q] the mouse that never drinks 



home to himself. It seems that rabbits sometimes enlarge 

 one of his entrances and move in. So probably does an 

 occasional snake, who cannot be a very welcome house 

 guest. Moreover, though Dipos probably have a home 

 base, they take refuge in the nearest hole when danger 

 threatens and they must often be surprised by what they 

 find there. 



In Austi-alia there is also a kangaroo rat which really is 

 a kangaroo — a marsupial that is, complete with a pouch 

 in which to carry its young. Sticklers say it should be 

 called rather a "rat-kangaroo" just as, so these same stick- 

 lers insist, an aviator ought to be called a "manbird" and 

 only an ornithologist a "birdman." But, in any event, Dipo 

 is a rodent, not a marsupial, and the only true American 

 marsupial, the 'possum, does not live in the arid South- 

 west. Nevertheless Dipo gets his common name from the 

 obvious fact that he looks like a kangaroo — because of his 

 long tail, his stubby little forelimbs which are not much 

 good for walking, and his habit of sitting or jumping on 

 his long hind legs. Like a real kangaroo he will also box 

 with a neighbor while sitting on his tail and striking out 

 with his hands. 



In the gobbledygook of technical description, all the 

 species of Dipodomys are said to be "admirably adapted to 

 a bipedal, saltatory existence." In other words, they jump 

 on their hind legs! Even in captivity and though normally 

 rather placid creatures, they may, when some not-too- 

 amiabie brush between one and another takes place, sud- 

 denly begin to bound erratically a foot and a half high 

 and to land after each bound no one can predict where. 

 But why? The ability to do without water is obviously a 

 very useful accomplishment for a desert dweller. What 



