THE STEPPES OF INNER AFRICA. 183 



and including many forms which are regarded as distinctive of this 

 geographical region. Of some of these we shall give rapid sketches. 



Among the most remarkable steppe animals are those fishes 

 found in the water-courses and water-basins which are only periodi- 

 cally filled. Even Aristotle speaks of fishes which burrow in the 

 mud when the pools are dried up, and though Seneca sought to 

 throw ridicule on the statement by suggesting scoffingly that one 

 should henceforth go a-fishing not with hook and line but with pick 

 and shovel, Aristotle recorded a fact which is beyond either doubt 

 or ridicule. 



The mud-fish,** which lives in the steppe basins and streams in the 

 interior of Africa, is an eel-like creature, about 3 feet in length, 

 with a long dorsal fin continuous with that of the tail, with two 

 narrow pectoral fins far forward, and two long pelvic fins far back, 

 and with this most important characteristic, that, besides the gills, 

 there are also functional 'lung -sacs. This remarkable connecting 

 link between fish and amphibian lives, even in the wet season, more 

 in the mud than in the water, and likes to hide in holes which it 

 seems to dig out for itself. When the supply of water threatens to 

 disappear, the fish burrows deeply in the mud, rolls itself into the 

 smallest possible bulk, and forms, apparently by frequent turning, 

 an air-tight capsule, shut in on all sides, and lined internally with 

 mucus. Within this the animal remains motionless throughout the 

 winter. If we carefully dig out these capsules and pack them well, 

 we can send the fish without risk where we please, and it may be 

 readily recalled to life by placing the capsule in lukewarm water. 

 As the reviving water soaks in, the creature still remains quiet, just 

 as if it were heavy with sleep; but in the course of an hour or so it 

 becomes quite lively, and in a few days its voracious hunger also 

 awakes. For some months its behaviour remains unaltered, but at 

 the season when it prepares in its native haunts for winter-sleep, it 

 seeks to do the same in captivity, or at least becomes restless, and 

 secretes an extraordinary quantity of mucus. If opportunity be 

 afforded, it burrows; if not, it soon masters its inclination, and con- 

 tinues to thrive as before in the open water. 



Sheat-fish or siluroids also pass the winter in the steppe as the 



