18 BULLETIN 1032, U. S. DEPARTMENT OF AGRICULTURE. 
hundred feet in one flight, and it is thus that bogs neighboring badly 
infested ones, especially to the leeward, may become badly infested 
in a few seasons. 
Other ways in which the fireworm is disseminated over a bog have 
been mentioned, namely, in the egg state, on leaves floating over the 
bog in the winter water (p. 7-8) , and also on cuttings (p. 4-5) . 
Proportion of Sexes. 
In 1918, of 158 moths of the first generation emerging in the in- 
sectary, 81, or 51 per cent, were males, and 77, or 49 per cent, were 
females; of 59 moths of the second generation, 24, or 41 per cent, 
were males, and 35, or 59 per cent, were females. In 1919, of 101 
moths of the first generation emerging in the insectary 53, or about 
52 per cent, were males, and 48, or about 48 per cent, were females ; 
of 52 moths of the second generation 24, or 46 per cent, were males, 
and 28, or 54 per cent, were females. This shows a slight predomi- 
nance of males over females in the first generation and the opposite 
in the second generation. 
Copulation. 
Copulation usually occurs shortly after emergence. Of those pairs 
observed in the rearing shelter, one was found copulating the same 
day it emerged, two the day after emergence, and one pair did not 
copulate until 7 days after emergence. The same pair was never 
seen to copulate more than once. 
The period of copulation varies in length, the minimum period 
observed being 1 hour and 26 minutes and the maximum 26 hours and 
55 minutes. The male of one pair observed was noted dead and still 
attached to the female 3 days after copulation was first observed. 
Oviposition. 
Egg-laying commences shortly after copulation, usually within a 
few days. During oviposition the female rather quickly pushes the 
egg out through the tip of the abdomen, which she holds very close 
to the underside of the leaf. Here the egg, a soft, plastic drop, settles 
over the surface and soon assumes its ordinary flat, oval shape. The 
outermost covering, which is rather moist when the egg is first laid, 
dries and cements the egg to the leaf and gives it its appearance of 
being glued on. (See fig. 1, a.) 
Time of Day When Oviposition Occurs. 
Eggs may be laid at almost any hour of the day and evening when 
the weather is warm and fair. However, in order to determine the 
time of day when the moths were depositing eggs in largest numbers, 
