306 THE ZOOLOGIST. 



colour varies somewhat : in large well-grown specimens it is 

 sandy, but I have noticed that in small Jerboas it may have a 

 distinct greyish tinge. The tail is brownish, tipped with black 

 and white. 



When standing "at ease" the Jerboa uses its tail as a kind 

 of third leg, this tripod arrangement recalling similar habits 

 practised by other mammals widely differing from the Jerboa — 

 such as Kangaroos or Wallabies, and perhaps also the huge 

 extinct Megatherium of South America. The Jerboa presses its 

 tiny fore legs close to the chest, and the body projects forwards. 

 When moving this little animal employs one of two gaits : (1) a 

 quick run, each leg being moved alternately ; and (2) a series of 

 tremendous leaps, the long tail being held out straight behind, 

 as if to counterbalance the forwardly directed head and body. I 

 well remember a fine male, which I still possess, escaping from 

 his prison, and the great rapidity with which he bounced along 

 over a wide lawn, as if made of animated india-rubber, the tiny 

 fugitive progressing at a lightning speed that rendered pursuit 

 hopeless. His final recapture was effected by strategy. 



Jerboas are usually stated to be nocturnal ; so no doubt they 

 are to a large extent, but by no means entirely so. They are at 

 any rate also crepuscular, if not diurnal, my own animals being 

 lively at all hours, retiring to rest irregularly for a longer or 

 shorter interval. When asleep they repose either huddled up 

 in a furry ball (head tucked in and tail coiled round them), or 

 else lying on one side. The latter position was rather horrifying 

 at first, suggesting that the Jerboa had departed this life ; how- 

 ever, a dead Jerboa either lies flaccid with limbs extended, or 

 else rolls over on its back, the long legs sticking up in the air. 

 These animals are lethargic in wet and foggy weather, and sleep 

 much later in the day than when it is dry and warm. On 

 rousing up for the evening the Jerboa frequently opens its eyes, 

 and remains motionless in a dozing semi-somnolent condition 

 for perhaps half an hour or an hour before becoming fully active. 

 It then begins to clean itself with great care, smoothing its fur, 

 and paying special attention to the terminal tuft of the tail, the 

 hair of which is absurdly parted down the middle in the neatest 

 possible manner. The Jerboa also frequently stretches itself in 

 the most amazing fashion, extending itself to the utmost, so that. 



