130 ANIMAL INTELLIGENCE. 



Espinas also observed (' Thierischen Gresellschaften,' 

 German translation, 1879, p. 371) that each single ant 

 made its own plan and followed it until a comrade, which 

 had caught the idea, joined it, and then they worked to- 

 gether in the execution of the same plan. 



Moggridge says of the harvesters of Europe, 



I have observed on more than one occasion that when in 

 digging into an ants' nest I have- thrown out an elater larva, 

 the ants would cluster round it and direct it towards some 

 small opening in the soil, which it would quickly enlarge and 

 disappear down. At other times, however, the ants would take 

 no notice of the elater, and it is my belief that the attentions 

 paid to it on former occasions were purely selfish, and that 

 they intended to avail themselves of the tunnel thus made 

 down into the soil, with the view of reopening communications 

 with the galleries and granaries concealed below, the approaches 

 to which had been covered up. I have frequently watched the 

 ants make use of these passages mined by the elater on these 

 occasions. 



And again, as showing apparently intelligent adaptation 

 of their usual habits to altered circumstances, he gives an 

 account of the behaviour of these ants when a great 

 crowd of them were confined by him in a glass jar con- 

 taining earth. He says : 



On the following morning the openings were ten in number, 

 and the greatly increased heaps of excavated earth showed that 

 they must probably have been at work all night. The amount 

 of work done in this short time was truly surprising, for it 

 must be remembered that, eighteen hours before, the earth pre- 

 sented a perfectly level surface, and the larvae and ants, now 

 housed below, found themselves prisoners in a strange place, 

 bounded by glass walls, and with no exit possible. 



It seems to me that the ants displayed extraordinary intelli- 

 gence in having thus at a moment's notice devised a plan by 

 which the superabundant number of workers could be em- 

 ployed at one time without coming in one another's way. The 

 soil contained in the jar was of course less than a tenth part of 

 that comprised within the limits of an ordinary nest, while the 

 number of workers was probably more than a third of the total 

 number belonging to the colony. If therefore but one or two 

 entrances had been pierced in the soil, the workers would have 

 been for ever running against one another, and a great number 



