THE GERBOA. 



589 



Like the kangaroos, the Spring Haas prefers rough and rocky ground to a smooth 

 soil, and displays such wonderful agility as it leaps from spot to spot, that it can baffle 

 almost any foe by its mere power of jumping. At a single leap this creature will com- 

 pass a space of twenty or thirty feet, and is able to continue these extraordinary bounds 

 for a great distance. It is rather a mischievous animal, as, like the common hare, it 

 is in the habit of making nocturnal raids upon the corn-field, and escaping safely to its 

 subterranean burrow before the sunrise. 



With the exception of shorter ears, and the elongated hinder limbs, the Spring Haas 

 is not unlike our common hare. The fur is of a dark fawn, or reddish-brown, percept- 

 ibly tinged with yellow on the upper parts, and fading into grayish-white beneath. In 

 texture it is very similar to that of the hare. The tail is about as long as the body, and 

 is heavily covered with rather stiff hairs, which at the extremity are of a deep black hue. 

 Upon the fore-legs there are five toes, which are armed with powerful claws, by means 

 of -which the animal digs its burrows, while the hinder feet are only furnished with four 

 toes, each of which is tipped with a long and rather sharply pointed claw. 



SPRING HAAS.Heiamys Capensls. 



THE Jerboidae find their best type in the common GERBOA of Northern Africa. 



This beautiful and active little animal is hardly larger than an ordinary English rat, 

 although its peculiar attitudes and its extremely long tail give it an appearance of 

 greater dimensions than it really possesses. The general color of its fur is a light dun, 

 washed with yellow, the abdomen being nearly white. The tail is of very great 

 proportionate length, as cylindrical in shape, and tufted at its extremity with stiff black 

 hairs, the extreme tip being white. From various experiments that have been made 

 upon this member and its use to the animal, it appears that the tail is of infinite service 

 in preserving the proper balance of the body while the creature is flying through mid- 

 air in its extraordinary leaps ; for in proportion as the tail was shortened, the power of 

 leaping diminished, and when it was entirely removed, the animal was afraid to leap at 

 all. Such truncated specimens were almost deprived of all power of locomotion, for 

 they could never preserve their balance as they rose upon their hinder feet, but rolled 

 over on their backs. As the Gerboa rises from one of its huge bounds for the purpose 



