102 
THe Army-worm, (Leucania unipuncta, Haw). 
Fig. 22.—Army-worm (Leucania unipuncta, Haw). Larva and chrysalis. 
The army-worm appeared in destructive numbers throughout South- 
ern Illinois in March and April of this year, attacking especially 
the grass and wheat, but did not attract general attention until 
later in the season. Another brood of the worms appeared in June, 
in Central Illinois, doing no serious damage, however, except in 
restricted localities. As a contribution to the life history of this insect 
the following dates of its appearance are noted. A living moth was 
taken at Normal on the 1sth of March. A colony of half grown 
worms was seen at Bloomington on the 22d of June, and on the 
24th another colony of about the same age was noticed in the lawn 
of the poor farm, six miles below that city. On the 50th, moths 
were found very abundant at Normal on the blossoms of red clover. 
On the 1st of July many young army-worms in the first and second 
stages occurred upon the grass at Normal; and on the 38d of that 
month the brood noticed at the poor farm had all pupated in the 
sround, while on the 12th moths were taken very abundantly at 
sugar at Normal. On the 27th, however, the moths were scarce at 
sugar, but on the ist of August a few larve, about three-eighths of 
an inch long, were noticed in a field of oats in McLean county. 
We have here, consequently, evidence of three distinct broods in 
Southern and Central Illinois, although the cold and wet weather 
of the early spring was especially unfavorable to the development 
of insect life. 
Near Centralia, damage was done by this worm in strawberry 
fields, the foliage being eaten and the unripe berries gnawed from 
their stems. 
The history of the brood of worms observed near the poor farm, 
in McLean county, is worthy of especial attention, as showing the 
power of the checks to which this species is subject, and serving to 
explain why two successive injurious broods rarely or never appear 
in the same locality. When first noticed, ca the 24th of June, these 
worms were doing serious damage to a heavy growth of timothy 
on high ground, marching from one side of the lawn to the other. 
By the 3d of July, the season for the transformation to pupe had 
been reached, but apparently not over twenty-five per cent. of the 
worms succeeded in effecting the change, the remainder dying in 
such numbers that the ground was reeking with a sickening stench. 
At the same time clusters of the cocoons of one of the common 
parasites of the army-worm were found everywhere abundant on the 
surface of the ground, and in some cases on the dried remains of 
the army-worm itself. Of seventy-six pup of the worm, collected 
in this field at this time, but one reached maturity. 
