130 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 
expensive, to keep up large fires during the whole or greater part of 
the night; and daring the last decade a great many lamps have been 
invented to take the place of fires. A lamp is more effective in attract- 
ing the moths than is a large open fire; for the heat and smoke of the 
latter scare away great numbers. Where lamps are employed there 
must be connected with them devices to kill the moths that are attracted 
by the light, and such killing is best accomplished by placing the lamps 
in pans filled with various substances of a sticky or destructive nature. 
During the earlier part of the summer of 1879 extensive experiments 
were made by Mr. Schwarz at Columbus, Tex., to test the efficacy of 
lamps. Though it was already too late in the season to cbeck the in- 
crease of the insect, some of the results are not without interest. The 
number of moths nightly killed by a single lamp varied very much ac 
cording to its location, but averaged not more than six specimens in the 
latter part of June, the number increasing rapidly during the next month. 
It was also found that these lamps attract and kill an immense number 
■of other insects. Among these are many injurious insects, asHeliothis 
■armigera (the parent of the Boll Worm), which, by the way, appears to 
be more readily attracted than the Cotton Moth, and several species of 
May-beetles (Lachnosterna) and others; but also, unfortunately, large 
numbers of the natural enemies of the Cotton Worm, as the nocturnal 
Tiger-beetles, Ground-beetles, and some of the Heteroptera already men- 
tioned. Above all, ft was found that the moths were not prevented from 
ovipositing even in the immediate vicinity of the lamps, and that on the 
-fields where the lamps had been used there were no less eggs deposited 
than on those where no lamps had been kept burning. It becomes ques- 
tionable, therefore, whether the lamps are not more productive of harm 
than good, especially at times when the moths are numerous. However, 
df, as is doubtless the case, the hibernating moths fly about early in 
the spring, then this will be the best time to use lamps in places where 
the moths have been seen flying, as in the vicinity of gin-houses, &c. 
In the month of March and in the earlier part of April they should be 
placed at those spots in the fields where the first worms have been ob- 
served in previous years. 
During the month of March, 1882, we instructed Mr. Koebele, then 
at Archer, Fla., to try on several successive nights to attract the moths 
by lights. Though freshly deposited eggs were constantly found at this 
season, and it was certain, therefore, that the hibernated moths were fly- 
ing about, yet not a single specimen was attracted by the lamps. This 
result is certainly not encouraging, but it must be remembered that 
success in this method of collecting largely depends on locality, on the 
state of weather, and on other conditions. 
Experiments made under our direction have proved that during moon- 
light nights fires or lamps have but little attraction for the moths, and, 
further, that better results are obtained before than after midnight. 
The only instance with which we are familial where lamps (those made 
