Order LEPIDOPTERA 
Butterflies, moths, skippers. 
This is the second largest order of insects and one of the most 
important economically. More than 5,000 species occur in eastern 
United States alone, and many are serious pests of forest, shade, 
and ornamental trees. The adults differ considerably in appear- 
ance from those in all other orders and are not difficult to recog- 
nize. The wings and practically all other parts of the body are 
typically covered by a layer of short, flattened hairs, or scales, 
which rub off like dust when the insects are handled. The mouth 
parts, when present, are in the form of a long, slender, flexible 
tube which is carried coiled up like a watch spring beneath the 
head. The wings are asually very broad, sub-triangular in form, 
and the front pair is larger. 
Moth, butterfly, and skipper adults usually differ in habits and 
appearance as follows: (1) Moths usually fly at night and are 
frequently attracted to lights; butterflies and skippers fly in the 
day time. (2) Moths usually have the wings wrapped around the 
body, folded roof-like on the abdomen, or spread horizontally 
while at rest; butterflies usually fold their wings above the back 
in a vertical position; skippers usually hold the front and hind- 
wings at a different angle. (8) Moth antennae are usually 
thread-like or feather-like; butterfly antennae are thread-like and 
clubbed at the tip; the antennae of the skippers are usually re- 
curved or hooked. 
Lepvidopterous larvae are all very similar in structure. They are 
usually cylindrical in shape, and, besides the head, the body is 
composed of 13 segments, three thoracic and 10 abdominal. Each 
thoracic segment bears a pair of jointed legs, terminating in a 
single claw, whereas the abdominal segments bear unjointed 
fleshy projections of the body called prolegs, typically one pair 
each on segments three to six and 10. Occasionally, some or all of 
the prolegs are missing. A distinctive feature of the prolegs of 
Microlepidoptera is the presence of fine hooks, known as crochets, 
usually in a circle at the apex. The crochets usually form bands 
or rows. Another important characteristic of the Lepidoptera is 
the ability of the larvae to produce silk. Many larvae use this 
material in making cocoons, and some use it for making shelters. 
The first instar larvae of certain species also frequently drop 
down from the crowns of trees in large numbers when disturbed, 
hanging suspended at the ends of long strands of silk. Many of 
these are often borne aloft by the wind and transported for con- 
siderable distances. Many nearly full grown larvae descend the 
tree in search of better food or pupation sites. 
True silk moth larvae typically spin silken cocoons in which 
to pupate. Some miscellaneous groups form tough silk or parch- 
ment-like cocoons, often with debris. The pupae of many others 
are naked or are enclosed in slight cocoons of attached leaves. 
Depending on the species, these cocoons may be found in the soil, 
in tunnels in wood, or in other larval habitats. The caterpillars of 
butterflies usually do not make cocoons. Their pupae are naked 
and are commonly known as chrysalids. They are often attached 
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