INSECTS. 
491 
caterpillar has, however, eight or ten other legs on the 
hinder segments of its body. The head has twelve eyes, 
and two very short conical antennae; and the mouth is 
furnished with two strong mandibles, two maxillae, a la- 
brum, and four pulpi. 
The habits of caterpillars differ ; some, which are 
called surveyors, fix themselves to a leaf with their fore 
and hind feet close together, and their bodies bent in the 
form of a loop ; others assemble in great numbers, and 
spin themselves a silken tent, under which they live : and 
others stretch themselves out like a piece of dry stick, 
which they very much resemble. Many make themselves 
cocoons ; but others have no other covering in the pupa 
state than a smooth shining skin, or a dark mummy-like 
cerement The chrysalis of a butterfly is generally angu- 
lar, and that of a moth cylindrical. 
TORTOISE-SHELL BUTTERFLY. (Vanessa urtica. 
THE Caterpillar which feeds on the nettle is about an inch 
in length, covered with bristles, and of a reddish brown 
