

STEPPES AND DESERTS. 19 



cious and cunning, the mule seeks a different mode of 

 alleviating his thirst. The ribbed and spherical melon- 

 cactus ( 37 ) conceals under its prickly envelope a watery pith. 

 The mule first strikes the prickles aside with his fore feet, 

 and then ventures warily to approach his lips to the plant 

 and drink the cool juice. But resort to this vegetable 

 fountain is not always without danger, and one sees many 

 animals that have been lamed by the prickles of the cactus. 

 When the burning heat of the day is followed by the 

 coolness of the night, which in these latitudes is always of 

 the same length, even then the horses and cattle cannot 

 enjoy repose. Enormous bats suck their blood like vam- 

 pires during their sleep, or attach themselves to their backs, 

 causing festering wounds, in which musquitoes, hippobosces, 

 and a host of stinging insects, niche themselves. Thus the 

 animals lead a painful life during the season when, under 

 the fierce glow of the sun, the soil is deprived of its 

 moisture. At length, after the long drought, the welcome 

 season of the rain arrives ; and then how suddenly is the 

 scene changed ! ( 38 ) The deep blue of the hitherto per- 

 petually cloudless sky becomes lighter ; at night the dark 

 space in the constellation of the Southern Cross is hardly 

 distinguishable ; the soft phosphorescent light of the Magel- 

 lanic clouds fades away ; even the stars in Aquila and 

 Ophiucus in the zenith shine with a trembling and less 

 planetary light. A single cloud appears in the south, like 

 a distant mountain, rising perpendicularly from the horizon. 

 Gradually the increasing vapours spread like mist over the 

 sky, and now the distant thunder ushers in the life-restoring 



