38 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 
I. What is the result of your experience or observations as to the efficacy of Paris 
green, or other arsenical compounds mixed with flour or plaster, for the destruction of 
the cotton-caterpillar ? 
II. In what proportions, and in what mode, time, and frequency of application have 
experiments been made f 
III. Have any injurious effects of the poison been observed, either upon the plants 
or the soil, or in human poisoning in its application, or in the destruction of beneficial 
insects, as bees, &c. ? 
IV. Have you used any other remedies, or means of extirpation, such as fires or 
torches in the fields to destroy the perfect moths on their first appearance, and with 
what success? 
Yours, respectfully, 
FRED'K WATTS, 
Commissioner. 
The answers to this circular, published in the Department report for 
1873, showed that the green was tried during the season in seven States 
and seventy counties, and that its success had been almost uniform. 
The same year several patents were taken out for poisonous mixtures 
to be used in destroying the Cotton Worm, and some of them reached 
a great sale for a few years — notably Preston & Kobeira's " Texas Cot- 
ton Worm Destroyer," and Johnson's "Dead Shot." But it has become 
generally understood that the same ingredients can be used in slightly 
differing proportions without infringing upon the patents, so that at the 
present day the patents are generally disregarded. 
In the Monthly Eeport of the Department for November and Decem- 
ber, 1872, Mr. E. H. Derby, of Boston, remarking upon the fact that the 
worm would not eat jute, suggested that a belt of that plant around a 
cotton-field might keep the worm away. A year later, in the Monthly 
Eeport for November and December, 1873, Mr. E. La Franc, president 
of the Southern Ramie Planting Association, detailed experiments with 
three fields, which seemed to prove the practicability of the use of jute 
as a preventive. Subsequent experiments, however, have failed, and it 
is probable that from this article of Mr. La Franc's have spread the 
numerous reports of the efficacy of jute, which are to be found in the 
back files of many Southern papers. 
Since 1873 most of the advance in remedies has been in the way of 
invention or improvement of machinery for the distribution of the poi- 
sonous mixture upon the plants. This machinery will be fully discussed 
in the chapter on remedies. 
The cheap arsenical poison known as London Purple was first expe- 
rimented upon as a Cotton Worm remedy by us during the season of 
1878, and the favorable results which followed its use induced extensive 
experiments the next year. 
It is hardly necessary to add that it has grown into great favor wher- 
ever it has been obtained pure and has been judiciously used. 
The only remaining remedy of importance — Pyrethrum — was first 
publicly recommended by the writer lor this purpose in first edition of 
this work, our first experiments with it upon the worms having been 
made during the summer of 1878. 
