DR. EMIL HOLUB. 195 
lakes,* all the wading and swimming birds of the neighbor- 
hood flock every evening to these waters, so as to avoid 
nightly attacks of the many small robbers, as jackals, hyenas, 
earthwolves and polecats, which infest these plains of the 
South African high plateau. 
During these observations of ours an hour has passed ; 
the sun’s golden disk is just touching the western horizon; 
in the east the shadows of the coming night are visible. As 
our eyes glance over the blue sky above, adorned here and 
there with a few light, feathery clouds, glad in the golden- 
crimson of the sun’s last farewell greetings, we perceive in 
the far distance, near the horizon and on all sides, a few 
darkish spots. Is it a delusion or not that they come 
nearer? We look hither and thither and it seems as if these 
spots become larger; they appear to approach. And they 
are approaching; they darken and are rapidly increasing in 
their breadth. Are they not swarms of locusts? Locusts? 
Hardly possible! No, they are not these ravenous insects. 
The locusts come with the wind and pass over in a single 
dark cloud, darkest just above the ground; but those ap- 
proaching clouds come from all directions. Some fly very 
high in the air, others from twenty to fifty yards high, others 
again move—as you can see—along the wavy grass; and 
suddenly this one cloud—now surely it is a swarm of birds 
—swerves aloft. Birds! Behold,—are they all birds, these 
approaching clouds? Yes, they are, and, to our great sur- 
prise, small, dark birds. We watch two of these large 
swarms, which from due north are making straight for us. 
They pass abreast for a few moments; suddenly the one to 
the left turns high up, lowers itself just as suddenly, and 
now both swarms, turning toward each other, have united in 
* Up to severai miles in diameter, and from one to two and a half feet 
deep in the centre, some with a few sweet water springs on their banks. 
They are everywhere in country which has no communication with the 
ocean, and are commonly called “saltpans,” being the lowest places in 
southern portions of the high plateau—the reservoir for rain-water. 
