322 ANT-LIONS. Chap. XVI. 



new cauoes for six strings of cheap coarse white beads 

 each, or their equivalent, four yards of calico, and had 

 bought for the merest trifle ivory enough to load them all. 

 They were driving a trade in slaves also, which was some- 

 thing new in this part of Africa, and likely soon to change 

 the character of the inhabitants. These men had been living 

 in clover, and were uncommonly fat and plump. When sent 

 to trade, slaves wisely never stint themselves of beer or 

 anything else, which their master's goods can buy. 



The insects called ant-lions (Myrmecoleo), were very nu- 

 merous in sandy places under shady trees, even where but 

 few ants were to be seen. These patient creatures lie in 

 ambush, and have a great deal of extra labour at this season 

 of the year. The high winds fill up their pitfalls with drift- 

 ing sand, and no sooner have they carefully shovelled it all 

 out, than it is again blown in, thus keeping them constantly 

 at work till the wind goes down. 



The temperature of the Zambesi had increased 10° since 

 August, being now 80°. The air was as high as 96° after 

 sunset ; and, the vicinity of the water being the coolest part, 

 we usually made our beds close by the river's brink, though 

 there in danger of crocodiles. Africa differs from India in the 

 air always becoming cool and refreshing long before the sun 

 returns, and there can be no doubt that we can in this 

 country bear exposure to the sun, which would be fatal in 

 India. It is probably owing to the greater dryness of the 

 African atmosphere that sunstroke is so rarely met with. In 

 twenty-two years Dr. Livingstone never met or heard of a 

 single case, though the protective head-dresses of India are 

 rarely seen. 



When the water is nearly at its lowest, we occasionally 

 meet with small rapids which are probably not in existence 

 during the rest of the year. Having slept opposite the rivulet 



