110 ANIMAL INTELLIGENCE. 



merely a rough and primitive way of communicating to 

 fellow-workers the locality where their services are re- 

 quired. He says : — 



Keeping these facts in mind, we have a key to the solution 

 of the press-gang operations which Lin cecum observed among 

 the agriculfcurals, and which have been fully described in other 

 species. In the absence of any common head or directory, and 

 of all executive officers, a change of location or any other con- 

 certed movement must be carried forward by the willing co- 

 operation of individuals. At first sight, the act of seizing and 

 carrying off workers does not appear like an appeal to free-will. 

 It is indeed coercive, so far as the first act goes. But, in point 

 of fact, the coercion ceases the moment the captive is set down 

 within the precincts of the new movement. The carrier-ant 

 has depended upon securing her consent and co-operation by 

 thus bringing her within the circle of activity for which her 

 service is sought. As a rule, no doubt, the deported ant at 

 once yields to the influence around her, and drops into the ' 

 current of fresh enterprise, in which she moves with as entire 

 freedom and as independently as any other worker. But she is 

 apparently under no restraint, and if she so please, may return 

 to her former haunts. 



Certain Ants of Africa, — Livingstone says of certain 

 ants of Africa : — 



They have established themselves on the plain where water 

 stands so long annually as to allow the lotus and other aqueous 

 plants to come to maturity. When all the ant-horizon is sub- 

 merged a foot deep, they manage to exist by ascending to Uttle 

 houses built of black tenaceous loam on stalks of grass, and 

 placed higher than the line of inundation. This must have 

 been the result of experience, for, if they had waited till the 

 water actually invaded their terrestrial habitations, they would 

 not have been able to procure materials for their aerial quarters, 

 unless they dived down to the bottom for every mouthful of 

 clay.^ 



The Tree Ant of India and New South Wales, — These 

 ants are remarkable from their habit of forming nests only 

 in trees. According to Col. Sykes' account, the shape of 

 the nest is more or less globular, and about ten inches in 

 diameter. It is formed entirely of cow-dung, which the 



1 Missionary Trowels, p. 328 



