Page:The Zoologist, 4th series, vol 5 (1901).djvu/334

306 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; however, 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,