Vol. XXvii] ENTOMOLOGICAL NEWS. 2/5 



of a few feet. It was a voluntary motion (i. e., they were not 

 merely carried by the wind, etc.), and yet there was no more 

 evidence of the leadership of one or more individuals in the 

 movement than there is evidence of one particle of fog lead- 

 ing a moving cloud. These changes were made so gradually 

 and smoothly that the observer could scarcely notice them 

 until he became aware that he must change his position to 

 watch them. 



The insects were so imbued with life and activity that I at 

 once suspected that close observation would show this to be 

 the marriage dance of this new species, so for four hours I 

 watched them in an effort to solve their behavior. 



It was soon apparent that, whatever the origin and signifi- 

 cance of this frolic, it might safely be called a sun-dance, for 

 they centered their dances only in the brightest spots of sun- 

 shine, where no leaf or twig marred the light. 



They were almost always on the wing, but here and there 

 a tired individual would drop to a leaf to rest, preen her an- 

 tennae, brush her abdomen or wings with her hind legs, or 

 rest quietly until she was chased away by another eager for a 

 mate. They were never observed to rest on the ground, al- 

 though in spots along the path the vegetation was sparse enough 

 to encourage it. 



While the great mass of the insects was whirling and danc- 

 ing most of the time, I did not observe among them a single 

 copulation or an attempt toward it on the wing, but among 

 those which fell out of the dance and dropped down upon the 

 leaves a very playful kind of mating frequently occurred. 

 When a female alighted, she usually enjoyed only a moment's 

 rest before she was disturbed by a male who pursued her, 

 running backwards and attempting to mate. Sometimes he 

 was active enough to catch her and accomplish a brief mating 

 on the run ; at other times he barely touched her abdomen as 

 she reached the end of the leaf and fell off, when he would fly 

 away into the dance again. 



In this species the male does not mount the female as is the 

 manner of some insects, but they always mate by the tips of 

 the abdomens, with their heads in opposite directions. In 



