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which to deposit their eggs, lay them on trees, grass, &e. The cold weather 
soon sets in and prevents their being hatched, and it is not until the warm days 
of spring come that the worm comes out. The number of worms hatched would 
be necessarily small, as numbers of eggs would be lost from various causes, 
cold, ac.) °'* in * The moth or fly belongs to the nocturnia tribe of 
the moth family. They commence their flight at sundown or a little before, 
and continue until 10 or 11 o’clock, darting with a quick zigzag motion from 
one stalk to another, nearly always selecting the tallest and most vigorous 
plants on which to deposit their eggs. I have not been able to form any cor- 
rect estimate of the number of eggs laid by one individual, but have counted 
nearly 500 squeezed from one. e id * 
On the 5th day of this month I placed ten well-grown worms in a vase and 
kept them well supplied with food. On the 9th and 10th they quit eating and 
seemed indisposed to move. On the 10th and 11th they commenced webbing 
by drawing a web from one side of a leaf to the other very tight, which caused 
the leaf to bend or curl a little; they then drew another a little tighter, and so 
on until the leaf was bent so as to form a tube, inside of which they placed 
themselves and lined it with a fine delicate web. Some I did not allow to have 
a leaf; they suspended themselves from a stem and commenced a slow spiral 
motion, and in about twenty-four hours had assumed the pupa state, being en- 
closed in a horny covering, through which the rudimentary wings and legs could 
be seen ; those inside the leaf undergoing the same changes. * x On 
the 17th the fly emerged from the pupa state, but was weak and hardly able to 
fly for about twenty-four hours. On the 20th, and possibly 19th, they com- 
menced to lay, and on the 24th the first worms made their appearance, but were 
too small to be seen without the aid of a glass. They grew very slowly for 
the first three or four days, but after that very rapidly, eating several times 
their own weight every day. ‘hey seem to eat more in the evening and in 
the morning than any other time; in fact, it is rare to see them eat during the day 
They have now, the 1st of September, almost attained their full size. I think 
my dates and figures are correct, as I took every precaution. The stalk of cotton 
on whith my flies laid their eggs grew in the garden until the first of this 
month, when I transplanted it to a jar, since which time it has been in the house 
and under a mosquito bar ‘where all the flies and worms were kept. When I 
put itin the jar 1 brushed and examined every leaf, and if there had been any 
eggs on them they would have surely hatched before the 20th, or certainly 
before the 25th. I allowed no one to go into the room. 
I think if there was any systematic course pursued by the planters, the cot- 
ton could be in a great measure protected. Suppose the planters in every 
neighborhood should keep a strict look-out in the spring, and as soon as the first 
worm appears give the alarm, and then examine and destroy all that could be 
found, continuing the examination from week to week and destroying all while 
worms, or as soon as they are webbed up. I think they could be all killed in 
this way, or at least held in check. It would be useless for one planter to do 
this, as the worms would fly from one place to another, but if all would act to- 
gether some good could surely be done. We know the fly lays at least 500 
eggs; now for every worm of the first generation destroyed we cut off 250,000 
from the third. The labor of killing the worms is not as great as it would 
seem at first sight, as they are not scattered over the field, but are found in 
patches until they increase so as to cover all. There are several other peculiari- 
ties of the worms I have neglected to mention ; one, that when touched, instead 
of curling up, as most worms do, they suddenly contract at the two extremities 
and spring several inches. My ideas may be wrong, but the figures are not. 
Very respectfully, JAMES M. FERGUSON 
