OUR SIX-FOOTED RIVALS. 203 



On the other hand, Mr. Tennant tells us that Formica smaragdina, 

 in forming its dwellings by cementing together the leaves of growing 

 trees, adopts the following method : A line of ants, standing along 

 the edge of one leaf, seize hold of another, and bring its margin in 

 contact with the one on which they are posted. They then hold both 

 together with their mandibles, while their companions glue them fast 

 with a kind of adhesive paper which they prepare. If the two leaves 

 are so far apart that a single ant cannot reach from one to another, 

 they form chains with their bodies to span over the gap. The same 

 author also informs us that certain Ceylonese ants, when carrying 

 sand or dry earth for the construction of their nests, glue several 

 grains together so as to form a lump as large as they can carry, and 

 thus economize time and labor. 



Mr. Belt, in his "Naturalist in Nicaragua" (page 2*7), gives the 

 following account of the manner in which the JEcitons, or foraging 

 'ants of Central and South America, deal with what may be called 

 engineering difficulties : " I once saw a wide column trying to pass 

 along a crumbling, nearly perpendicular slope. They would have 

 got very slowly over it, and many of them would have fallen, but 

 a number having secured their hold and reaching to each other re- 

 mained stationary, and over them the main column passed. Another 

 time they were crossing a water-course along a small branch, not 

 thicker than a goose-quill. They widened this natural bridge to three 

 times its width, by a number of ants clinging to it and to each other 

 on each side, over which the column passed three or four deep ; where- 

 as, except for this expedient, they would have had to pass over in 

 sino-le file, and treble the time would have been consumed." 



Again, in Eciton legionis, according to Mr. Bates, when digging 

 mines to get at another species of ant whose nests they were attack- 

 ing, the workers were divided into parties, " one set excavating and 

 another set carrying away the grains of earth. When the shafts 

 became rather deep the mining parties had to climb up the sides each 

 time they wished to cast out a pellet of earth, but their work was 

 lightened for them by comrades who stationed themselves at the 

 mouth of the shaft and relieved them of their burdens, carrying the 

 particles, with an appearance of foresight which quite staggered me, 

 a sufficient distance from the edge of the hole to prevent them from 

 rolling in again." 



What, then, are we to learn from these somewhat inconsistent 

 cases ? Are we to conclude that Sir John Lubbock, Mr. Belt, Mr. 

 Bates, and Mr. Tennant, must be careless and incompetent observers ? 

 Assuredly not. Are we to believe that ants are stupid, irrational 

 creatures, and that when they do anything right it must be regarded 

 as an accident or ascribed to that convenient phantom, instinct? 

 Still less : the well-established cases which are on record agree badly 

 with either of these suppositions. The true explanation of the diffi- 



