HEMIPTERA. 131 
in the middle of its stem a small sphere, to which it served as the 
axis. It was a case which the ants had constructed of earth. 
They issued forth from this by a very narrow opening made in 
its base, descended the stem, and passed into a neighbouring ants’ 
nest. I destroyed one part of this pavilion, built almost in the 
air, so that I might study the interior. It was a little room, 
whose vault-shaped walls were smooth and even. The ants had 
profited by the form of the plant to sustain their edifice. The 
stalk passed up the centre of the apartment, and for its timber- 
work it had the leaves. This retreat contained a numerous family 
of plant-lice, to which the brown ants came peacefully, to make 
their harvest, sheltered from the rain, the sun, and from other 
ants. No insect could disturb them, and the plant-lice were not 
exposed to the attacks of their numerous enemies. I admired this 
trait of industry, and I was not long in finding it again, in a more 
interesting character, in ants of different species. 
“Some red ants had built round the foot of a thistle a tube of 
earth, two inches and a half long by one and a half broad. The 
ants’ nest was below, and communicated directly with the cylinder. 
I took the stalk, with what surrounded it, and all that the cylinder 
contained. That portion of the stem which was inside the earthen 
tube was covered with plant-lice. I very soon saw the ants coming 
out of the opening I had made at the base; they were very much 
astonished to see daylight at that place, and I saw that they 
lived there with their larvee. They carried these with great haste 
to the highest part of the cylinder which had not been altered. 
In this retreat they were within reach of their plant-lice, and here 
they fed their young. 
“Tn other places many stalks of the euphorbia laden with plant- 
lice rose in the very centre of an ant-hill belonging to the brown 
ants. These insects, profiting by the peculiar arrangement of the 
leaves of this plant, had constructed round each branch as many 
little elongated cases; and it was here they came to get their food. 
Having destroyed one of these cells, the ants forthwith carried off 
into their nests their precious animals; a few days afterwards it 
was repaired under my eyes by these insects, and the herd were 
taken back to their pens. 
“These cases are not always at a few inches from the ground. 
K 2 
