ARTIIROPODA. 
301 
colors, and are often arranged in patterns of exquisite 
beauty. They are in reality modified hairs, and every 
family has its partic¬ 
ular form of scale. 
The head is small, 
and the body cylin¬ 
drical. The legs are 
not used for locomo¬ 
tion. All the mouth 
parts are nearly obso¬ 
lete except the maxil¬ 
lae, which are fash¬ 
ioned into a “ probos¬ 
cis ^ for pUinpinfiT up P IG -272.—Part of the Wing of a Moth ( Saturnia ), 
r r & r magnified to show the arrangement of scales. 
the nectar of flowers. 
The larvae, called “ caterpillars,” have a worm-like form, 
and from one to five pairs of abdominal legs, in addition 
to the three on the thorax. The mouth is formed for mas¬ 
tication, and (ex¬ 
cept in the larvae 
of Butterflies) the 
lip has a spinneret 
connected with silk- 
glands. 
There are three 
groups : the gay 
Butterflies, having 
knobbed or hooked 
antennae, and flying 
in the day only; 
the dull-colored Sphinges, with antennae thickened in the 
middle, and flying at twilight; and the nocturnal Moths, 
which generally prefer the night, and whose antennae are 
thread-like and often feathery. Generally, when at rest, 
the Butterflies keep their wings raised vertically, while 
Fig. 273.— Vanessapolyehloros, or “Tortoise-shell But¬ 
terfly.” 
