37 
The writer has found the beetles in numbers about the roots of pig- 
weed (Ambrosia), and other persons have noticed them about weeds. 
Although the species is rather unusually periodical in injurious attack, 
it is obviously capable of doing much damage in years when it develops 
in great numbers. 
NATURAL ENEMIES AND METHODS OF CONTROL. 
One bird, the chuck-will’s-widow, is recorded as having fed on the 
beetles of Zigyrus gibbosus at Gainesville, Tex. (Ins. Life, Vol. LI, p.189). 
It is to be regretted that when this insect is present in large num- 
bers in cultivated fields there is little, owing to its manner of working, 
that can be accomplished in the line of control. About the only thing 
that can be done is to trap the beetles at night by means of stationary 
lanterns and pans of water placed below the lanterns, on which is float- 
ing a thin scum of kerosene. The lanterns should be stationed at 
intervals about the field, particularly around the borders. The beetles 
are strongly attracted to electric lights, but it is not certain that they 
could be lured from the fields after beginning to feed. 
A correspondent reports that by scattering lime through infested 
fields the beetles have been apparently driven away. It is possible 
that this or some other similar substance might have a deterrent effect, 
but it is rather doubtful. 
After the crop has been harvested, if the insects continue in numbers 
in the ground, either in the adult, larval, or pupal stage, it would be 
profitable to turn in hogs, which soon find and root up such insects 
from the ground. Chickens also learn to follow the plow after these 
and similar insects. Crop rotation should also be practiced. 
THE BEET ARMY WORM. 
(Laphygma exigua Hbn. ) 
Simultaneously with the occurrence of the fall army worm (Za- 
phygma frugiperda) in the eastern United States in such unusual and 
destructive numbers in 1899, as previously reported by the writer 
(Bul. 29, n. s., pp. 5-46), a similar outbreak of a related species known 
in American literature as Laphygma flavimaculata Harv. occurred in 
Colorado and New Mexico. The outbreak in Colorado has been men- 
tioned by Prof. C. P. Gillette in several publications, but no compre- 
hensive account of the species has yet been published, and recent 
studies of literature show thit there is such a strong possibility of this 
species becoming a serious pest eastward that it becomes a practical 
necessity to bring together all that we know about it. All that has 
been published in regard to its food habits and ravages in America are 
from the observations of Professor Gillette, but through the kindness 
of Dr. H. G. Dyar, of the National Museum, I have been referred to 
numerous articles on this species going to show that it is widely dis- 
