.835.] ‘SWARM OF LOCUSTS. 329 
character from the Strait of Magellan, along the whole eastern 
coast of Patagonia, to the Rio Colorado; and it appears that the 
same kind of country extends inland from this river, in a sweep- 
ing line as far as San Luis, and perhaps even further north. To 
the eastward of this curved line, lies the basin of the compara- 
tively damp and green plains of Buenos Ayres. The sterile 
plains of Mendoza and Patagonia consist of a bed of shingle, 
worn smooth and accumulated by the waves of the sea; while 
the Pampas, covered by thistles, clover, and grass, have been 
formed by the ancient estuary mud of the Plata. 
After our two days’ tedious journey, it was refreshing to see 
in the distance the rows of poplars and willows growing round 
the village and river of Luxan. Shortly before we arrived at 
this place, we observed to the south a ragged cloud of a dark 
reddish-brown colour. At first we thought that it was smoke 
from some great fire on the plains; but we soon found that it 
was aswarm of locusts. They were flying northward ; and with 
the aid of a light breeze, they overtook us at a rate of ten or 
fifteen miles an hour. The main body filled the air from a 
height of twenty feet, to that, as it appeared, of two or, three 
thousand above the ground ; “‘and the sound of their wings was 
as the sound of chariots of many horses running to battle :” or 
rather, I should say, like a strong breeze passing. through the 
rigging of a ship. The sky, seen through the advanced guard, 
appeared like a mezzotinto engraving, but the main body was 
impervious to sight; they were not, however, so thick together, 
but that they could escape a stick waved backwards and for- 
wards. When they alighted, they were more numerous than the 
leaves in the field, and the surface became reddish instead of 
being green: the swarm having once alighted, the individuals 
flew from side to side in all directions. Locusts are not an un- 
common pest in this country: already during this season, several 
smaller swarms had come up from the south, where, as apparently 
in all other parts of the world, they are bred in the deserts. 
The poor cottagers in vain attempted by lighting fires, by shouts, 
and by waving branches to avert the attack. This species 
of locust closely resembles, and perhaps is identical with the 
famous Gryllus migratorius of the East. 
We crossed the Luxan, which is a river of considerable size, 
