2l8 THE INDUSTRIES OF ANIMALS. 



growing colony. In opening an ant-hill, they are 

 found to be quite distinct from each other ; each is 

 divided by a large number of partitions into vaulted 

 compartments. In the larger ones pillars of earth 

 support the ceiling. The rooms communicate with 

 one another by means of bull's-eye passages formed 

 in the separating walls. The whole is small, propor- 

 tioned to the size of the works, but excellently 

 arranged. 



When, in the council of the republic, it has been 

 resolved to raise a common habitation, the workers 

 operate in a singular manner. All the ants scatter 

 themselves abroad, and with extreme activity take 

 fragments of earth between their mandibles and place 

 them on the summit of the dwelling. After some 

 time the result of this microscopical work appears. 

 The ancient roof, strengthened by all this material, 

 becomes a thick terrace which the insects first cover 

 very evenly. The earth, having been brought in grain 

 by grain, is soft and easy to dig. The construction of 

 the new storey begins at first by the hollowing out 

 of a number of trenches. The ants scrape away in 

 places the terrace which they have just made. They 

 thus diminish the thickness of the layer at the spots 

 where rooms, corridors, etc., are to be formed, and 

 with the material thus obtained they form walls, 

 partitions, and pillars. Soon the entire plan of the 

 new storey may be perceived. It differs essentially 

 from that which Man would adopt ; in the latter case 

 the walls would be shown by the hollowing out of the 

 foundations ; the work of these Hymenoptera, on the 

 contrary, shows them in relief These first arrange- 

 ments made, the six-footed architects have only to 

 complete their constructions by new deposits from 



