NATURE'S CRAFTSMEN 



causing their bodies to vibrate like a shaky vessel driven 

 by a huge engine. They act much as they do when 

 rushing in line or column to a battle-field. 



The winged forms share the common agitation, and 

 tmnble and crawl over one another, and spread their 

 gauzy wings that quiver and give forth a faint crackling 

 sound, and flash in the sunlight with iridescent colors, 

 as though Iris had looped upon them tiny bits of her 

 veil. And now, as if by one impulse, the emigrants 

 begin to take flight. Singly, in pairs, in groups, in 

 mass they rise, and flutter above the surface, rising or 

 falling, or weaving in and out of the swarm seemingly 

 in purposeless confusion. 



Sometimes I have seen two or three centres of migra- 

 tion several feet apart, as though they were neighboring 

 and fraternal nests of one species, or one widely extend- 

 ed colony. In either case one is amazed at the vast 

 numbers that pour out of the open gates, as if some 

 Cadmus of the insect world had called by magic an 

 army from the ground. If the nest-site happen to be 

 on well-known ground he will wonder all the more, for 

 the presence of such a multitude would never be suspect- 

 ed by anything actually seen. Whence have they come ? 

 Where and how have they been kept? 



The swarm reaches several feet above one's head or 

 swings around the face, so that one may readily see the 

 male lovingly escorting his companion, who is several 

 times larger than himself. At times, the swarms will 

 sink almost to the surface, when the lovers may be seen 

 dropping from the mass and continuing their courtship 

 on the grass. 



The course of a marriage flight is regulated by the 

 direction and force of the wind. It has no relation to 



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