202 NATURE'S TEACHINGS. 



shine, they construct as they go on a slight gallery, which looks 

 very much like the lining of a tunnel stripped of the surround- 

 ing earth. If their path should lead them to thick herbage, 

 sticks, &c., which form a protection from the sun, the Driver- 

 ants do not trouble themselves to make a tunnel, but take 

 advantage of the shade, and only resume the tunnel when they 

 reach the open ground. 



Sometimes, when they are on a marauding expedition, they 

 construct a tunnel in a very curious manner, their own bodies 

 supplying the materials. The reader must know that there afe 

 several classes of these insects, varying in size from that of a huge 

 earwig to that of the little red ant of our gardens. The largest 

 class seem to care little about the sunshine, the protection 

 being mostly needed by the workers. The following is 

 Dr. Savage's account of their proceedings: 



"In cloudy days, when on their predatory excursions, or 

 migrating, an arch for the protection of the workers is con- 

 structed of the bodies of their largest class. Their widely 

 extended jaws, long, slender limbs, and projecting antennae, 

 intertwining, form a sort of network that seems to answer well 

 their object. 



" Whenever an alarm is given, the arch is instantly broken, 

 and the Ants/ joining others of the same class on the outside of 

 the line, who seem to be acting as commanders, guides, and 

 beauts, run about in a furious manner in pursuit of the enemy. 

 If the alarm should prove to be without foundation, the victory 

 won, or danger passed, the arch is quickly renewed, and the 

 main column marches forward as before, in all the order of an 

 intellectual military discipline." 



How they should be able to direct their course, and to chase 

 an enemy, is not easy to understand ; for, as far as is known, 

 they are absolutely blind, not even an indication of an eye 

 being seen. 



THE SUSPENSION-BRIDGE. 



THE mention of these Ants brings us to another point in 

 architecture. We have already seen that they can not only 

 build arched tunnels, but also can form their own bodies into 

 arches, and we shall presently see how they can form them- 

 selves into Suspension-bridges. We will, however, first take 



