BEET WORMS AND THEIR REMEDIES. 7 
Ft. Collins in 1903 and about Rocky Ford and Sugar City during 
the first week of July, 1904. But it was the next, or third (?), 
brood that did most mischief in Colorado the past year. In the 
Northern portion of the State the worms were most destructive 
from the 10th to the 25th of August. 
Most moths are on the wing only after dark, or in the twi¬ 
light, but the moth that lays eggs to produce the beet web-worms 
is active in the day-time also and may be seen flying about the 
beets a week or ten days, at least, before the worms appear. 
THE EGGS. 
The eggs are sometimes deposited singly but usually in clus¬ 
ters or rows of from 2 or 3 to 8 or 10 together. They are oval in 
form, and about 1 millimeter long by .7 of a millimeter broad 
(one-twenty-fifth by one-thirty-sixth of an inch), and are quite flat 
below but strongly convex above. When clustered, the eggs are 
laid in a row, one overlapping upon another and making an angle 
of about 45 degrees with the surface of the leaf. In color they 
are a very pale green with a beautiful pearly reflection. They are 
deposited upon either the upper or lower surface of the leaves. In 
our breeding cages the greater number were deposited on the 
under surface. After once seeing them they are quite readily de¬ 
tected by the naked eye. They are shown once and a half natural 
size at a andV, Fig. 2, Plate I. At the end of about the second 
day there appears a small black speck upon the eggs as shown at 
c. This is the black head of the little worm that is developing 
within the shell. I11 about two or three days more the little worm 
eats a ragged exit hole in one end of the shell and escapes. 
THE WORM. 
The little worms are almost black at first and so small (one- 
sixteenth of an inch long) that they are easily overlooked. P A or 
the first two or three days the worms eat very little and skeleton¬ 
ize the leaves instead of eating entirely through them, but when 
they are about half grown and the white stripes begin to show 
plainly, they begin to eat and grow very rapidly so that the owner 
of the beets is often made to believe that the worms have migrat¬ 
ed in the night from an adjoining crop or field. I have seen no 
general migrations of the worms except in a few instances where 
their food supply had given out or become very scanty- A pecul¬ 
iarity of the attacks of this insect in nearly every case that I have 
observed is that the chief injuries are well in the fields and almost 
never at the borders. We have also noticed the injuries to be 
worse in the higher and dryer portions of the fields but we have 
not found the injuries more common on light than 011 heavy soil. 
On individual plants, the young tender leaves at the center were 
always the last to be eaten. 
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