MIGRATION AND DISPERSAL OF INSECTS '. HYMENOPTEEA, TERMITES. 209 



arrived. Sharp notes (Imecta, ii., p. 65) : " When a swarm of Apis 

 mellifica leaves a hive it consists of the queen bee and a number of 

 workers, these latter being, in fact, the surplus population that has 

 been produced in the hive ; the swarm is not a nuptial flight, as is so 

 often supposed, but an act of emigration." He adds {loc. cit., p. 67) : 

 " It is interesting to notice that, in confinement, when a swarm goes 

 from a hive, it is the old queen that accompanies it, and this swarm, as 

 a rule, settles down near the old hive, so that the queen bee, being 

 already fertilised, the new swarm and its subsequent increase are 

 nothing but a division of the old hive, the total products of the two 

 having but a single father and mother. When a second swarm goes 

 off from a hive it is accompanied by a young queen, who frequently, 

 perhaps in the majority of cases, is unfertilised ; this swarm is apt to 

 fly for long distances, so that the probability of cross-fertilisation is 

 greatly increased, as the fertilisation of the young queen is effected 

 during a solitary flight she makes after the colony has settled down. 

 But, in a state of nature, the colonies do not send off swarms every 

 year or once a year, but increase to an enormous extent, going for 

 years without swarming, and then, when their home is really filled up, 

 send off", it may be presumed, a number of swarms in one year. Thus 

 the phenomena of bee life in a wild condition differ considerably from 

 those we see in artificial confinement." A rather remarkable occur- 

 rence is noted by Baly {Ent., vii., p. 293) who observed that, in early 

 October, 1874, a swarm of bees issued from one of his hives, and that, 

 after remaining in the air for a few minutes, making the usual hum- 

 ming noises they suddenly returned, clustering round the entrance of 

 the hive for a little time before re-entering. The hive was not more 

 than a third full of comb, the stock small, and examination of the hive 

 gave no clue as to the cause of this movement. Smith stn.tes (Trans. Ent. 

 Soc. of Land., 1868, p. 133), on the authority of Peckolt, that one of the 

 stingless bees, Trif/ona mosquito, sends off swarms after the manner of 

 the hive-bee in this country, and that, after searching six hives, only 

 one royal female could be found in each. Von Ihering has recently 

 shewn {Ann. Nat. History, (6), xix., 1897, p. 136) that social insects 

 in Brazil may be divided into two great groups by their habits, viz., 

 (1) Summer communities lasting for one year, and founded annually 

 by fertilised females that have hibernated — example, Polistes. (2) 

 Perennial communities founded by swarms after the fashion of bee 

 colonies — examples, Polybia, Cliartrryns. 



The migration of ants, is, in many respects, analogous with the 

 swarming of bees. The swarms of male ants, however, which are 

 driven from the nests by the workers during the summer months, and 

 which occasionally form dense clouds, and have frequently been 

 described by various observers, are not of this nature. When queen 

 ants migrate they usually fly off from the nest singly, although they 

 have been found with workers (which are wingless) attached to their 

 bodies, undoubtedly to aid them in the foundation of a new colony. 

 The " swarming" of the males and the migration of the female ants 

 take place, however, almost at the same tiine, whilst the number of 

 males that may be produced in a single nest seems almost incredible. 

 The winged males usually appear a day or two before the females of the 

 same nest, and, forming a swarm, fly away from the near neighbourhood 

 of their own nest, often uniting on their journey with similar bodies of ants 



