ANTS AND ANT LIFE. 91 



from their nests outwards, but spread themselves over all 

 the lines whereon roads are to be made (as in the building of 

 a new nest), begin the work simultaneously at all points, 

 and then behave just as men do in making a railway, high- 

 road, or similar work. The roads sometimes extend to a 

 distance of eighty and even of a hundred yards from the nest, 

 and eight or ten of thes^ will be made from a large nest. 

 The wood ants, as a rule,, make no roads, as their passage 

 from one tree to another is attended with no difficulty. 



The covered ways, galleries, or tunnels are, as a rule, 

 built by those ants which visit their milch-cows, the Aphides, 

 secretly, and need to hide these from other ants or from 

 their countless other enemies. If the tunnel passes through 

 a quiet out-of-the-way place, where no danger is to be 

 feared, they leave off the roof and the road is open. Forel 

 saw such a road, two centimetres broad and one centimetre 

 high, built of earth and covered in, which was taken up a 

 low wall and down again on the other side, merely to secure 

 a safe way from a court into a garden. Sometimes they 

 walled round the stalks or stems of the plants on which 

 they kept Aphides, so that the latter were quite shut in, and 

 made rooms for them of the leaves of the plants. Lasius 

 brunneus, the brown ant, almost lives by keeping very large 

 cochineal insects, and protects its roofs by help of their 

 rotted skins. In the same way Kermes, and especially the 

 gall-insects, are sometimes regularly walled in by ants. 

 Their prison is generally tolerably large, and has small 

 openings, by means of which the caretakers slip in and out, 

 while the outgoing of the prisoners is prevented. Forel 

 -aw such a prison, shaped like a cocoon, about a centimetre 

 long, hanging on an oak branch, and containing Aphides, 

 which were carefully looked after by the ants. In the 

 chapter on " Cattle-care and milking" more will be said on 

 this. 



Forel had special opportunities of observing that ants are 

 able to perfect themselves in their tunnel-making (as in their 

 various other works). He kept a colony of M. coespitum 

 (turf-ants) imprisoned in a tray walled round with pulverised 

 gypsum, so that the gypsum gave way under climbing and 

 the ants fell down. This went on for a fortnight, until it 

 struck the ants to try to escape by making a tunnel through 

 the powder. Many efforts were rendered futile by the fall 



