INSECT ENEMIES OF EASTERN FORESTS 367 
DISCUSSION OF FAMILIES AND SPECIES 
In the following pages most of the species are treated individually 
but are grouped by families. An attempt has been made to include all 
species of importance as pests in the forests of the Eastern States. 
Tn addition many others are included, the larvae of which occasionally 
become abundant locally in this region and cause considerable con- 
cern when attacking trees, shrubs, or vines in the forest or those grown 
for shade and ornamental purposes. In some families consisting of 
species g generally of little economic importance, a discussion is given 
tor only one or two o representatives. 
Whenever possible a brief description of the full-grown larva is 
given for each species, but generally the adults of only the more 1m- 
portant species are described. Information is also given on the dis- 
tribution, the food plants, the life history, and the ‘habits, as far as 
they are known, and any other data considered important. 
The control of forest’ and shade tree insects is discussed elsewhere 
in this manual (see section on The Control of Forest Insects). When 
artificial control measures are considered necessary to protect the 
fohage of trees, shrubs, and vines against the ravages of lepidopter ous 
larvae, the timely application of a stomach poison such as lead _ar- 
senate or DDT, will control the species that feed externally. For 
cautions in the use of these materials see pp. 25 and 34. Therefore, 
in the discussion of such species, no reference is made to artificial con- 
trol unless other methods are also recommended. 
For species such as leaf miners and various types of borers, which 
need special treatment when control practices are necessary, the proper 
measure is given under the discussion of the insect, or reference is 
made as to where it can be found. 
Faminry PAPILIONIDAE 
Among the species included in the family Papilionidae are our well- 
known swallowtail butterflies, so-called because of the wavy margin 
and tailiike prolongation of the hind wings. Their larvae are not 
hairy or spiny, but in some species the body bears fleshy filaments. 
The first thoracic segment of each bears a protrusive bright-colored, 
forked process, capable of emitting a disagreeable odor, which un- 
doubtedly is used as an organ of defense. 
Although some species are generally quite common, only occasion- 
ally do any of them become abundant enough to necessitate artificial 
control. 
The adult of the pipe-vine swallowtail (Battus philenor (L.)) has 
a wing expanse of about 4 inches; the forewings are black with green- 
ish-metallic reflections, and the hind wings are brilliant steel blue with 
greenish reflections. The full-grown larva is about 2 inches long, 
velvety black with a brownish tint, and covered with long fleshy 
tubercles of the same color, and shorter ones of orange (fig. 7 0, A). 
It is distributed through the Eastern States, nor th to Massachusetts 
and occasionally in V ermont, and is also recorded from Arizona. 
Mexico, and southern California. The larvae feed on species of 
Aristolochia and often seriously defoliate dutchmans-pipe, both in 
nurseries and when grown as an ornamental vine out of doors. There 
are usually two generations. The adults emerge in May and June and 
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