THE BLACKHEAD FIEEWOEM OF CEAjSTBEEEY. 



17 



often have a light golden-brown sheen. The antennae are about one- 

 half the length of the body and more or less bristlelike. 



The adults live from 3 to 33 days after they emerge, and during this 

 time eat little or nothing, except, perhaps, a little nectar from the 

 blossoms, or water in the form of dew or rain. 



Habits of Flight. 



After the moth emerges from the pupal case it rests for a short time, 

 during which the wings are spread and dried. It then starts to fly 

 and moves rather swiftly in a short, jerky, darting motion, making 

 usually only short flights from place to place over the vines. Par- 

 ticularly on heavily infested bogs the moths are very conspicuous for 

 their habits of flight. 

 They will often be seen 

 to rise in large numbers 

 when disturbed, as by 

 spraying or by a person 

 walking through the 

 vines on a warm after- 

 noon, suggesting to some 



the appearance 

 cloud. 



of 



Periods of Activity. 



A few moths may 

 generally be seen flying 

 from tip to tip almost 

 every hour of the da.j 

 from the time of their 

 first appearance in June 

 until late in September 

 and October, but the time of day they are most active is from aoout 

 3 o'clock in the afternoon until after dusk. During this period, 

 especially if the weather is warm, they may be seen to rise in the air 

 for a few feet, making their characteristic short, jerky flights. 



Fig. 9. — Tlie adult or moth at rest on a cranberrj' up- 

 right. Enlarged about 6 times. 



Migration. 



It is in the moth stage principally that the blackhead fireworm 

 spreads itself over the bog or invades an adjoining one. The moth, 

 however, flying only short distances, would not naturally migrate 

 more than several yards from its original region of activity; but, 

 helped by the wind, it is possible for it to be carried as far as several 

 74890°— 22 3 



