130 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION. 



expensive, to keep up large fires during the whole or greater part of 

 the night; and during 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. Wliere lamps are employed there 

 must be connected with them devices to kill tlie moths that are attracted 

 by the light, and such killing is best accomplished by placing the lamps 

 iin 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 check 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, aiiEeliotUs 

 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, it 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. Ho wetter, 

 if, 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. 

 Jn 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- 

 tserved 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- 

 iug 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 familiar where lamps (those made 



