6 FARMERS’ BULLETIN 634. 
the stalk, they turn downward, penetrate to the extreme lower tip 
of the taproot, and there form a small cavity in which to pass the 
winter. At this time the larve lose the darker markings of the ear- 
lier forms, and as overwintering larve are creamy-yellow in color. 
They are plump and active in the fall, but flabby and sluggish after 
fasting throughout the winter. The only way in which the insect 
passes the winter is in the form of this overwintering larva, found 
below the ground in the extreme lower tip of the corn roots. Two 
generations a year appear to be the rule, although it is possible that 
in the far South and on sugar cane a partial third generation may 
occur. 
DESCRIPTIONS. 
EGG. 
The eggs are flat and scalelike, almost circular in outline, and are 
placed in rows or irregularly, overlapping one another shingle fashion. 
From 2 to 25 eggs are laid in one place on the underside of a lower 
leaf or occasionally on the upper side and on the stem. Creamy-white 
when first laid, they gradually change to a reddish-brown, and in 7 to 
10 days a minute, bristly, reddish caterpillar cracks the shell and 
crawls out through a narrow slit at one end. The eggs are about 
three one-hundredths of an inch (7.6 mm.) long and about two-thirds 
as wide. After hatching, the white papery shells are soon washed off 
the leaves. 
LARVA. 
The larva of the first generation (fig. 1, a) when full grown is a 
robust, dirty-white caterpillar 1 inch in length, thickly covered with 
round or irregular dark spots, each of which bears a shert, dark 
bristle. When the larva is small these markings are almost contig- 
uous, giving the whole insect a dark color and a hairy appearance. 
The head and thoracic plate of all the stages are brownish-yellow. 
_The overwintering larva of the second generation (fig. 1, 6, c) gradu- 
ally loses the darker markings of the body and after the last molt 
remains unspotted and light yellow in color, except for the head and 
the thoracic plate, which retain the brownish-yellow of the earlier 
stages. 
PUPA. 
When first formed, the pupa (fig. 4, c) is light honey-yellow in 
color, soon changing to a rich mahogany-brown. It is about seven- 
eighths of an inch in length and is able to contort itself violently 
when disturbed. It lies in the cavity, usually with the head up. 
On emerging, the moth leaves the brownish shell of the pupa case 
partially withdrawn from the hole. 
ADULT. 
The female moth (fig. 4, a) varies in color from almost white 
to smoky yellow. The fore wings, which spread to about 1} inches, 
