378 PERFECT SOCIETIES OF INSECTS. 



again In the night, at about eleven o'clock, and found ray ants busy milk- 

 ing their cows, which did not for the sake of repos^intermit their suction. 

 At the same hour another night, I observed the little negro-ant (^F. fusca) 

 engaged in the same employment upon an elder. About two miles from 

 my residence was a nest of Gould's hill-ant (P. rufa), which, according 

 to M. Huber, shut their gates, or rather barricade them, every night, and 

 remain at horne.^ Being desirous of ascertaining the accuracy of his 

 statement, early in October, about two o'clock one morning, I visited this 

 nest in company with an intelligent friend ; and to our surprise and admi- 

 ration we found our ants at work, some being engaged in carrying their 

 usual burden, sticks and straws, into their habitation, others going out 

 from it, and several were climbing the neighboring oaks, doubtless to milk 

 their Aphides.- The number of comers and goers at that hour, however, 

 was notiiing compared with the myriads that may always be seen on these 

 nests during the day. It so happened that our visit was paid while the 

 moon was near the full ; so that whether this species is equally vigilant 

 and active in the absence of that luminary yet remains uncertain. Per- 

 haps this circumstance might reconcile Huber's observation with ours, and 

 confirm the accuracy of Aristotle's statement before quoted. To the red 

 ant, indeed, it is perfectly indifferent whether the moon shine or not ; 

 they are always busy, though not in such numbers as during the day. It 

 is probable that these creatures take their repose at all hours indifferently ; 

 for it cannot be supposed that they are employed day and night without rest. 

 I have related to you in this and former letters most of the works and 

 employments of ants, but as yet I have given you no account of their 

 roads and trackways. Don't be alarmed, and imagine I am going to 

 repeat to you the fable of the ancients, that they wear a path in the 

 stones-; for I suppose you will scarcely be brought to believe that, as 

 Hannibal cut a way for the passage of his army over the Alps by means 

 of vinegar, so the antsmay with equal effect employ the formic acid : but 

 more species than one do really form roads which lead from their formi- 

 caries into the adjoining country. Gould, speaking of his jet-ant (F. fuli- 

 ginosa,) says that they make several main track-ways (streets he calls 

 them), with smaller paths striking off from them, extending sometimes to 

 the distance of forty feet from their nest, and leading to those spots in 

 which they collect their provisions ; that upon these roads they always 

 travel, and are very careful to remove from them bits of sticks, straw, or 

 any thing that may impede their progress ; nay, that they even keep low 

 the herbs and grass which grow in them, by constantly biting them off**, 

 so that they may be said to mow their walks. But the best constructors 

 of roads arc the hill-ants (F. rufa). Of these De Geer says, " When 

 you keep yourself still, witliout making any noise, in the woods peopled 

 with these ants, you may hear them very distinctly walking over the dry 

 leaves which arc dispersed upon the soil, the claws of their feet producing 

 a slight sound when they lay hold of them. They make io the ground 

 broad paths, well beaten, which may be readily distinguished, and which 

 are formed by the going and coming of innumerable ants, whose custom 

 it is always to travel in the same route."^ From Huber we further learn 



» Huber, 23. » Plin. Hist. Nat. Ixi. c. 29. » Gould, 87. 



* Pe Geer, ii. 1067. 



