INSECT ENEMIES OF EASTERN FORESTS 119 
The boxelder bug may be controlled early in the spring by spraying 
infested trees with a contact spray containing pyrethrum, used at the 
strength recommended by the manufacturer for other plant bugs. 
When adults are congregating on or in houses large numbers may be 
destroyed simply by sweeping them up and burning them. Masses 
of bugs may also be destroyed by spraying or dusting them with an 
insecticide containing pyrethrum. Indoors, an ordinary fly spray con- 
taiming pyrethrum will probably prove effective. 
Famity LYGAEIDAE 
The lygaeids are commonly referred to as chinch bugs. This group 
varies greatly in size and habits. They are small to medium-sized, 
oblong or narrowly oval in shape, and ~ange from 2 to 18 mm. in 
length. Most species are dull colored although some are contrastingly 
marked with red and black. All species are characterized by the pres- 
ence of 4 to 6 veins in the membrane of the forewing. Many of the spe- 
cies are plant feeders, but the members of the large subfamily Rhypa- 
rochrominae are thought to be mainly predatory. The forelegs of this 
group have the femora swollen and armed beneath with spines. Spe- 
cies belonging to this predaceous group are frequently encountered in 
the duff covering of the forest floor. Some plant-feeding species may 
be numerous on herbaceous undergrowth. 
SusporpER HOMOPTERA 
The suborder Homoptera includes many divergent groups, differing 
in both size and appearance. Some of these, such as the males of cer- 
tain species of scale insects, are almost microscopic in size, whereas 
others, such as certain cicadas, may have a wing expanse of over 4 
inches. All are sucking insects, however, and all undergo a gradual 
metamorphosis. Some of these insects are winged, others are wingless ; 
some are motile, others are legless; some lay eggs, some give birth 
to living young, and still others may lay eggs at one period of their 
life cycle and give birth to living young at another. Some require the 
presence of males for the production of fertile eggs or living young, 
whereas others are parthenogenetic; some are relatively naked, and 
some are covered with wax in the form of threads, powder, plates, or 
scales. : 
In the feeding by members of this group, the degree of injury to 
plants ranges from comparatively little to the death of the host 
plant. Some species are injurious simply through their withdrawal 
of sap from plants; some cause injury by slitting twigs for the inser- 
tion of eggs; some cause the development of galls or other distortions; 
and others are indirectly injurious in serving as vectors of various 
destructive diseases. Species in the group may be found at one time 
or another on almost any part of plants, both above and below ground. 
The length of the life cycle in the group ranges from a few days (for 
aphids) to several years (for cicadas). 
Famity FULGORIDAE 
This family is mainly tropical in distribution, although certain spe- 
cies may be encountered frequently in the forests of the Eastern States. 
