256 



NATURE 



[Jan. 13, 1 88 1 



difference in the re.-ult, if on expeiimenting with two ants one 

 had access to a large treasure, the other only to a small one. 



It also occurred to me that some light would be thrown on the 

 question by compelling the aut who found the treasure to return 

 empty handed. If she took nothing home and yet others re- 

 turned with her, this must be by some commu)iication having 

 passed. It would be a case iu which precept was better than 

 example. 



I selected therefore a specimen of Atlatatacco pilosa, belonging 

 to a nest which I had brought back with me from Algeria. She 

 was out hunting about six feet from home, and I placed before 

 her a large dead bluebottle fly, which slie at once began to drag 

 to the nest. I then pinned the lly to a piece of cork, in a small 

 box, so that no ant could see the lly until she had climbed up the 

 side of the box. The ant struggled, of course in vain, to move 

 the fly. She pulled first in one direction and then in another, 

 but, finding her efforts fruitless, she at length started off back to 

 the nest empty-handed. At this time there were no ai.ts coming 

 out of the nest. Probably there were some few others out 

 hunting, but for at lea-t a quarter of an hour no ant had left the 

 nest. My ant entered the nest but did not remain there; in less 

 than a minute she emerged accompanied by seven friends. I 

 never saw so many come out of that nest together before. In 

 her excitement the first ant soon distanced her companions, who 

 took the matter with much j(j«^ _/}'(?;'(/, and had all the appearance 

 of having come out reluctantly, or as if they had been asleep and 

 were only half awake. The first ant ran on ahead, going straight 

 to the fly. The others followed slowly and with many meander- 

 ings ; so slowly, indeed, that for twenty minutes the first aiit was 

 alone at the fly, trying in every » ay to move it. Finding this 

 still impossible, she again returned to the nest, not chancing to 

 meet any of her fi'iends by the way. Again she emerged in less 

 than a minute with eight friends, and hurried on to the fly. They 

 were even less energetic than the first party ; and when they 

 found they had lost sight of their guide they one and all returned 

 to the nC't. In the meantime several of the first detachment 

 had found the fly, and one of them succeeded in detaching a leg, 

 with which she returned in triumph to the nest, coming out agam 

 directly with four or five companions. These latter, with one 

 exception, soon gave up the chase and returned to the nest. I 

 do nut think so much of this last case, because as the ant carried 

 in a sub tantiiil piece of booty in the shape of the fly's leg, it is 

 not surprising that her friends should some of them accompany 

 her on her return; but surely the other two cases indicate a 

 distinct power of communication. 



Lest however it should be supposed that the result was acci- 

 dental, I determined to tiy it again. Accordingly on the follow- 

 ing day I I ut another large dead fly before an ant belonging to 

 the same ne^t, pinning it to a piece of cork as before. After 

 trying in vain for ten minutes to move the fly, my ant started 

 off home. At that time I could only see two other ants of that 

 species outside the nest. Yet in a few seconds, considerably less 

 than a minute, she emerged with no less than twelve friends. As 

 in the previous case, she ran on ahead, and they fi flowed very 

 slouly and by no means directly, taking in fact nearly half an 

 hour to reach the fly. The first ant, after vainly labouring for 

 about a quarter of an hour to move the fly, started off again to the 

 nest. Meeting one of her friends on the way she tallied with her 

 a little, then continued towards the nest, but after going about a 

 foot, changed her mind, and returned with her friend to the fly. 

 After some minutes, during which two or three other ants canie 

 up, one of them detached a leg, which she carried off to the nest, 

 coming out again almost immediately with six friends, one of 

 whom, curiously enough, seemed to lead the way, tracing it, I 

 presume, by scent. I then removed the pin, and they carried 

 off the fly in triumph. 



These and other experiments certainly seem to indicate the 

 possession by ants of something approaching to language. It is 

 impossible to doubt that the friends were brought out by the first 

 ant ; and as she returned empty-handed to the nest, the others 

 cannot have been induced to follow her merely by observing her 

 proceedings, i conclude, therefore, that they 1 ossess the power 

 of requesting their friends to come and help them. 



RtcogiiUioii of Relations. — In my la-t paper (I.inii. Journ. 

 vol. xiv. p. 611) I recorded some experiments made with pups, 

 in order if possible to determire how ants recognised their nest 

 companions. The general result was that pupae tended by 

 strangers of the same species, and then after they had arrived 

 -t maturity put into the nest from which these strangers had been 

 taken, were invariably treated as inteilopers and attaclied. On 



the other hand, if they were tended by ants from their own nest, 

 and then after arriving at maturity put liack in their own nest, 

 they were invariably recognised as friends ; and lastly, if as pupse 

 they were tended by strangers, but then after arriving at maturity 

 put b.Tck in their own nest, they were generally received as 

 friends. In all these experiments, however, the ants were taken 

 from ihe nest as pup^, and though I did not think the fact that 

 they had passed their larval existence in the nest could affect the 

 problem, still it might do so. I determined therefore to separate 

 a nest before the young were born, or even the eogs laid, and 

 then ascertain the result. Accordingly I took one of my nests, 

 which I bejj.an watching on September 13, 1878, and which con- 

 tained two queens, and on February 8, 1879, divided it into 

 halves, which I will call A and B, so that there « e-e approximately 

 the same number of ants with a queen in each division. At this 

 season, of course, the nest contained neither young nor even 

 eggs. During April both queens began to lay eggs. On July 

 20 I took a number of pupce from each division and placed each 

 hit in a separate glass, with two ants from the same division. 

 On August 30 I took four ants fiom the pupa; bred in B, and 

 one from iho e in A (which were not quite si forward), and after 

 marking them .as usual with paint, put the B ants into nest A, 

 and the A ant into nest B. They were received amicably and 

 soon cleaned. Two, indeed, were once attacked for a few 

 moments, I ut soon released. On the other hand, I put two 

 strangers into nest A, but they were at once killed. For facility 

 of observation I placed each nest in a closed kox. On the 31st 

 I carefully examined the nests and also the boxes in wh'ch I had 

 placed them. I could only distingui.-h one of the marl^ed ants, 

 but there were no dead ants either in the nests or boxes, except 

 the two strangers. 



Some further experiments led to similar results. 



The^e observations seem to me conclusive as far as they go, 

 and they are very surprising. In my experiments of last year, 

 though the results were simdar, still the ants experimented with 

 had been brought up in the nest, and were only removed after 

 ihey had become pupa?. It might therefore be argued that the 

 ants having nur-ed them as larvK, recognised them when they 

 came to maturity ; and though this would certainly be in the 

 highest degree improbable, it could not be said to be impossible. 

 In the present case, however, the old ants had absolutely never 

 seen the young ones until the moment when, some days after 

 arriving at maturity, they were introduced into the nest ; and yet 

 in all ten cases they were undoubtedly recognised as belonging 

 to the community. 



It seems to me therefore to be established by these experi- 

 ments that the recognition of ants is not personal and individual ; 

 that their harmony is not due to the fact that each ant is indi- 

 vidually acquainted with every other member of the community. 



At the same time the fact that they recogniie their friends even 

 when intoxicated, and that they know the young born in their 

 own nest even when they have been brought out of the chrysalis 

 by strangers, seems to indicate ihat the recognition is not effected 

 by means of any sign or password. 



Workers brceJiitg. — In my last paper I brought forward some 

 strong evidence tending to show that when workers laid eggs 

 they always produced males. 1 his is, however, a physiological 

 fact of so much interest that I have carefully watched my nes's 

 this year also, to see what further light they would throw en the 

 subject. In six of those which contained no queen eggs were 

 produced, which of course must necessarily have been laid by 

 workers belonging to Lasius niger, Formica cinerea, Formica 

 fuse a and Polyergiis rufescens. 



The result w as that in five of these nests males have been pro- 

 duced, and in net a single case has a worker laid eggs -which 

 have produced a female, either a queen or a worker. Perhaps I 

 ought to add that workers are abundantly pre duced in those of 

 my nests which pos' e-s a queen. Again, as in previous years, so 

 this season again, while great numbers of workers and males 

 have come to maturity in my nets, not a single queen has been 

 produced. We have, I think, therefore, strong reason for con- 

 cluding that, as in the ca<e of bees, so also in anis, some special 

 food is rec]uired to develop the female embryo into a queen. 



As to //caring and Experiments with Telephone. — In order 

 to ascertain if possible whether ants made any sounds which 

 Were audible to one another, I thought I would try the tele- 

 phone. Accordingly I looked for two ants' nests (Lasius niger) 

 not far from one another, and then, after disturbing one 

 of them, hnd a telephone held ju-t over it. I then held the 

 second telephone close over the other nest, each telephone being 



