IMPERFECT SOCIETIES OP INSECTS. 15 



in full motion in the morning; immediately after the 

 evaporation of the clew ; and if no dew has fallen, they 

 appear as soon as the sun imparts his genial warmth. 

 At first some are seen running- about like messengers 

 among- the reposing swarms, which are lying- partly 

 compressed upon the ground, at the side of small emi- 

 nences, and partly attached to tall plants and shrubs. 

 Shortly after the whole body begins to move forward 

 in one direction and w ith little deviation. They re- 

 semble a swarm of ants, all taking the same course, at 

 small distances, but without touching each other : they 

 uniformly travel towards a certain region as fast as a 

 fly can run, and without leaping, unless pursued ; in 

 which case, indeed, they disperse, but soon collect 

 again and follow their former route. Tn this manner 

 they advance from morning- to evening without halting, 

 frequently at the rate of a hundred fathoms and up- 

 wards in the course of a day. Although they prefer 

 marching along high roads, footpaths, or open tracts; 

 yet when their progress is opposed by bushes, hedges, 

 and ditches, they penetrate through them : their way 

 can only be impeded by the w aters of brooks or canals, 

 as they are apparently terrified at every kind of mois- 

 ture. Often, however, they endeavour to gain the op- 

 posite bank with the aid of overhanging boughs ; and 

 if the stalks of plants or shrubs be laid across the wa- 

 ter, they pass in close columns over these temporary 

 bridges ; on which they even seem to rest and enjoy 

 the refreshing coolness. Towards sun-set the whole 

 swarm gradually collect in parties, and creep up the 

 plants, or encamp on slight eminences. On cold, 

 cloudy, or rainy days they do not travel. — As soon as 



