[28] REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 
this pea were adjacent to the cotton-field, I noticed the moths flitting about it in 
great numbers at night, and in evening twilight they were to be seen passing in 
swarms, as it were, from the cotton to the peas. I also saw moths of the Boll Worm 
feeding in the pea patches with large representation. 
Unlike the larva of Aletia that of Heliothis (Boll Worm) appears to be an insect of 
wide range so far as relates to its natural food. While it feeds upon the bolls of cot- 
ton with evident relish, thus leading us to call it the Boll Worm, cotton bolls do not 
appear to be its first choice by any means. It evidently has a decided preference for 
green corn, upon which it multiplies with greater thrift than upon any other culti- 
vated crop. I think that, of all the Cotton States, the Boll Worm does most damage 
to cotton in Texas, growing, I suppose, out of the fact that Texas raises the most 
corn. In all my observations I found the rule to hold good that where fields of early 
corn were adjacent to cotton the cotton crop sustained greater damage from Boll 
Worm than where they were not. This, according to my reasoning, is because the 
early broods of Boll Worms are advantageously raised upon the early corn, which 
eventually becoming too dry and hard for their purpose forces the insects to emigrate 
to the cotton fields for a propagation in later broods. 
ANNOYANCES TO THE COTTON WORM. 
I find it a thing by no means rare for planters to become suddenly carried away 
Trith the idea that they have just discovered complete remedies for the Cotton Worm, 
and for large districts to become considerably electrified over the discovery, when, in 
truth, the new remedies are nothing more than temporary annoyances thrown in the 
way of the insect and its work, and consequently worth very little indeed, if any- 
thing. Among the latest of these may be listed an application to the plants of a 
solution of 
Common salt. — Soon after reaching Texas I heard that the planters in certain local- 
ities of the State were effectually saving their crops from worms by sprinkling the 
plants with "brine," and it even got into the papers and took a general run all over 
the country, producing quite a commotion. Now, I had no faith whatever in salt as 
an insecticide, still, as the thing met me at every hand, I concluded to put it to the 
test. My applications were made with salt in solution ; No. 1 had two ounces of salt 
to the gallon of water, and No 2 three ounces of salt to the gallon. These solutions 
were thoroughly sprinkled over plants upon which Cotton Worms were at work in 
large numbers. Two days after the applications had been made I thought there were 
fewer worms on the plants sprinkled with No. 1 than before, while there was an un- 
doubted thinning out under the effect of No. 2. The leaves sprinkled with solution 
No. 2 were considerably scorched by the salt. No dead worms were found ; indeed 
the salt had been to them nothing more than a temporary annoyance, causing them 
to move to the adjacent plants not salted — I saw them going in considerable numbers. 
And the protection was only for a very brief season ; a few days later, when food be- 
came more scarce on the adjacent plants, those to which the applications had been 
made were restocked with worms and speedily stripped of their leaves. 
Saltpeter. — This salt (nitrate of potassa) also got into the papers upon the authority 
of some planter as a never-failing remedy for the Cotton Worm. He applied it in so- 
lution made by dissolving an ounce of the salt to the gallon of water. I put it to 
careful test, following his directions, and found it, like common salt (chloride of 
sodium), to be simply a temporary annoyance to the worms, and nothing more. 
Road dust. — A much traveled road ran east and west through one of the fields in 
which I was conducting my experiments. Early in the season the cotton on the south 
side of this road was badly damaged by the Cotton Worm, while for 40 feet along the 
northern side it had not been much disturbed. Investigation for the cause of the 
exemption showed it to arise from dust blown over the plants from the road by a pre- 
vailing wind from the south. The discovery seemed of value as a suggestion of the 
idea that a dry season, with strong winds blowing dust over the plants, may make 
an unfavorable condition for the growth and multiplication of the Cotton Worm. It 
is this possibly that has given rise to the notion that a dry season is less favorable for 
worms than a wet one. Although dry in Central Texas this season, there were no 
strong winds, not enough to carry dust from a road save in cases where it had first 
been stirred up by some other cause, as a passing vehicle, for instance. 
But in the case just mentioned the dust proved only a temporary annoyance to the 
insects ; later in the season the exempted cotton was entirely stripped by them. 
Open spaces. — It is noticeable that cotton plants growing immediately upon the 
border of open spaces, as along the sides of roads, or adjacent to crops of 1o\v*t 
growth, &c, are exempt from an attack by the worms longer than those growing in 
other parts of the field. A careful si udy of the case has convinced me that this is due 
to the extreme shyness of the moth, which prevents it from stopping and depositing 
its eggs in such exposed situations. Sea re it up in the daytime and it at once darts 
off to a place of concealment in the thickest growth it can find; and if you watch it 
