single female may lay up to 200 eggs on a chosen host plant. Others are laid singly or in small groups. They are round, slightly flattened, smooth and translucent or whitish. Larvae Saturniid caterpillars are large (50 to 100 mm in the final instar), stout, and cylindrical. Most have tubercules that are often also spiny or hairy. Many are cryptic in coloration, with countershading or disruptive coloration to reduce detection, but some are more colorful. Some have urticating hairs. A few species have been noted to produce clicking sounds with the larval mandibles when disturbed. Examples: Luna moth (Actias luna) and Polyphemus moth (Antheraea polyphemus). The clicks may serve as aposematic warning signals to a regurgitation defense. Most are solitary feeders, but some are gregarious. The Hemileucinae are gregarious when young and have stinging hairs, those of Lonomia containing a poison which may kill a human. Arsenura armida is another well-known example, and are infamous for their large conspicuous masses during the day. Their coloration is not cryptic, instead exhibiting aposematism. The other caterpillars in this size range are almost universally Sphingidae, which are seldom hairy and tend to have diagonal stripes on their sides. Many Sphingidae caterpillars bear a single curved horn on their hind end. These are actually not dangerous, but large-haired caterpillars should generally not be touched except by experts. Most saturniid larvae feed on the foliage of trees and shrubs. A few, particularly Hemileucinae such as Automeris louisiana, A. patagonensis, and Hemileuca oliviae, feed on grasses. They moult at regular intervals, usually four to six times before entering the pupal stage. Prior to pupation, a wandering stage occurs, and the caterpillar may change color, becoming more cryptic just before this stage. Pupae Most larvae spin a silken cocoon in the leaves of a preferred host plant or in leaf litter on the ground, or crevices in rocks and logs. While only moderately close relatives to the silkworm (Bombyx mori) among the Lepidoptera, the cocoons of most larger saturniids can be gathered and used to make silk fabric. However, larvae of some species – typically Ceratocampinae, like the regal moth (Citheronia regalis) and the imperial moth (Eacles imperialis), burrow and pupate in a small chamber beneath the soil. This is common in the Ceratocampinae and Hemileucinae. Unlike most silk moths, those that pupate underground do not use much silk in the construction. Once enclosed in the cocoon,