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F O R M I C I D JE. 



succeeded in overcoming the obstacles placed in their 

 way in order to secure those things from their attacks, 

 swimming over the water, in which the legs of the 

 tables were plunged, stepping, or rather jumping upon 

 the tables, when removed to a short distance from 

 the wall. Colonel Sykes proceeds : " The table was 

 now removed from the wall beyond the maximum 

 stretch of the largest ants, and I flattered myself I 

 had triumphed over their perseverance and ingenuity, 

 but, to my infinite surprise, in a few days the sweets 

 teemed, as usual, with the intruders, and I was 

 puzzled in no small degree to account for their 

 re-appearance. Accidentally passing the table, I 

 observed an ant upon the wall, about a foot above 

 the level of the sweets ; it fell, and, instead of passing 

 between the wall and the table, and alighting upon 

 the ground, the insect fell upon the table. Can it be 

 possible, I said to myself, that this fall is designed ? 

 I stood to observe with the most intense curiosity ; 

 another ant ascended, and dropped with similar suc- 

 cess ; another and another followed ; and there was 

 no longer doubt that instinct (if instinct I must call 

 it) had made them, in this instance, a match for 

 reason." 



The genus Polyergus ( Latreille) is distinguished by 

 having the antennae placed close to the mouth ; the 

 jaws are slender and curved, the sting wanting, and 

 the abdominal peduncle composed of a single joint. 

 The type of this genus is the Formica rufescens 

 (Latreille). This interesting species, although very 

 common in France, has not yet been discovered in 

 this country. At the present moment, however, a few 

 particulars relative to the slave-trade amongst insects 

 may not be thought uninteresting. 



A, Polyergus rufescens. B, Formica fusca. 



The indefatigable Huber, to whose researches upon 

 tnis family of insects entomologists are so much in- 

 debted, was the first author who noticed the remark- 

 able circumstances connected with their history. 

 Walking in the neighbourhood of Geneva one after- 

 noon, he observed a troop of these ants, eight or ten 

 feet long, and three or four inches broad, crossing the 

 path, and proceeding with rapid steps towards a nest 

 of the Formica fusca above described. On arriving 

 at its entrance, the latter (which are considerably 

 smaller in size) attacked the strangers, but were soon 

 put to flight, and retreated into their nest, pursued by 

 the victors, some of whom commenced making an- 

 other breach at the side of the nest, through which the 

 remainder entered. In three or four minutes, how- 

 ever, the Polyergi returned in haste, each holding in 

 its jaws a larva or a pupa ; and, loaded in this man- 

 ner, they succeeded in arriving at their own nest. 

 On returning to look at the state of the pillaged nest, 

 Huber found some of the black ants perched upon 



the adjacent grass, each holding a larva or pupa, 

 which it had saved from the pillage, and with which 

 they soon returned to their nest. The next day, 

 interested by this curious proceeding, our observer 

 returned to the spot, and again witnessed a similar 

 attack on another nest. Here, however, such of the 

 victors as could not secure a larva or pupa, united in 

 a body, and attacked a third nest, where they found 

 an ample supply. On returning to the nest of the 

 Polyergus, the surprise of M. Huber was infinitely 

 increased at observing a number of the black ants 

 themselves occupied upon and within the nest, and 

 appearing to be on the most friendly terms with the 

 Polyergi on their return from their marauding excur- 

 sion, feeding them, and touching them with their 

 antennae, &c. Never, observes M. Huber, did riddle 

 more strongly excite my curiosity than this singular 

 discovery ; and he fortunately succeeded in discover- 

 ing some of the nests close to his house, so that he 

 was able to observe them in a very satisfactory man- 

 ner. He thus noticed that the black ants were en- 

 gaged in repairing the nestwhicli he had opened, dig- 

 ging fresh galleries, and conveying into them the stolen 

 larvae and pupae ; whereas the Polyergi took no further 

 care about the latter, or the repairs of the nest, but 

 retired to the deepest parts of their abode. From a 

 long series of observations, it appeared certain that 

 the mixed nests belong to the Polyergi, and that 

 they are composed of three kinds of individuals of 

 this species, and of workers of the Formica fusca, no 

 males nor females of the latter being found in the 

 nest ; the larvae and pupae stolen are therefore those 

 of neuters, which are no sooner arrived at the imago 

 state than they share in the toils of their strange 

 masters' nests, all of which are in fact borne by them, 

 the Polyergi being unfitted for any other sort of 

 labour but war. That this is the case, is moreover 

 fully evident from the structure of their jaws, which 

 are the chief organs employed in the construction of 

 their abodes by the other ants, and which, in the 

 Polyergus, instead of being large and strongly toothed, 

 are slender, acute, and curved, and quite unfitted for 

 carrying heavy and rough materials. That the 

 situation of these slaves, toiling in a strange territory 

 for strange masters, instead of labouring for their own 

 community, cannot be regarded otherwise than as 

 unnatural, will not be denied ; but, when we reflect 

 that these slaves have been born in this state, without 

 knowing anything of a different state, that of freedom 

 that they toil not more laboriously for their masters 

 than they would do for themselves, were they free, 

 their instincts being essentially industrious, whether 

 slaves or free that they suffer no privations of food 

 or repose that they are even charged with the 

 rearing of some of their own kind and, moreover, 

 that the state of society, dependent upon the struc- 

 tural peculiarities of the Polyergus, noticed above, 

 requires their presence in the nest of the latter, we 

 shall cease to think that the condition of these slaves 

 is one of misery. 



The genus Ponera seems intermediate between the 

 preceding and following genera ; unlike the former, 

 the insects of which it is composed are furnished with 

 a sting, and different from the following in having the 

 abdominal peduncle composed of a single knot, the 

 second joint being nearly as large as the following, 

 from which it is, however, slightly separated at the 

 hinder margin. 



The type Ponera contracta (Latreille) is of a small 



