HEMIPTEEA. 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 larvae. 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. 



" In 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. 



K2 



