These horrible little pests are one of the biggest scourges of the desert. They are a species of tick that breed in the droppings of animals, and burrow in the sand of the immediate vicinity, lying low till some juicy, full-blooded victim comes along for them to perform upon. For this reason they are always plentiful under certain shady trees, favoured by oxen and big game as a resting-place in the heat of the day. Choose one of these spots and sit down in the pleasant shade and watch the sand around you. Not a sign of insect life for the first few minutes--and then! A tiny eruption in the sand near your elbow, and there, scratching his way to daylight--and you--comes the pioneer, followed by others till the whole earth is alive with them. And bite! So poisonous are they to some people that to be bitten badly leads to blood-poisoning, and in any case the intolerable itching from their bites spoils a man for sleep or anything else but scratching and inventing new profanity for days and days after he has been victimised. All of which I had known, and still Du Toit and his companion in crime had caught me beautifully, with the enticing shade of that big tree. They lay sleeping peacefully, a bare twenty yards away, under a bush thick enough to shade them and too small to have harboured oxen--or sam-pans. We followed the Khuisiep till late that evening, when we came to a water-hole where our horses drank, and near which we slept that night, not too near, for the immediate vicinity was literally buzzing with mosquitoes. The stagnant water was also full of their larvæ--so full that we strained it through a handkerchief before boiling a billy of it for coffee, and got a spoonful of larvæ to each billy. Still it was quite drinkable as coffee, much better than the oleaginous liquid Jim provided us with.