The forests of Brazil exhibit numerous beautiful examples of insect
workmanship. Among others is the work of a caterpillar--a cocoon about
the size of a sparrow's egg, woven in broad meshes of either buff or
rose-coloured silk, and seen suspended from the tip of an outstanding
leaf by a strong thread, five or six inches in length. It forms a
conspicuous object hung thus in mid-air. The glossy threads with which
it is knitted are stout, and the structure is not likely therefore to be
torn by the beaks of insectivorous birds; while its pendulous position
makes it doubly secure against their attacks, as the apparatus gives way
when they peck at it. There is a small orifice at each end of the
egg-shaped bag, to admit of the escape of the moth when it changes from
the little chrysalis which sleeps tranquilly in its airy cage.
Other caterpillars form cases with fragments of wood or leaves, in which
they live secure from their enemies, whilst they are feeding and
growing. Some of these, composed of small bits of stick, are knitted
together with fine silken threads, and others make tubes very like the
cadis-worms of English ponds. Others choose leaves, with which they
form an elongated bag, open at both ends, having the insides lined with
thick webs. As the weight of one of these dwellings would be greater
than the caterpillar inside could sustain, it attaches the case by one
or more threads to the leaves or twigs near which it is feeding.