A tussock moth (Lymantria dispar or Porthetria dispar or Ocneria dispar) native of the Old World, but accidentally introduced into eastern Massachusetts about 1869, where its caterpillars have done great damage to fruit, shade, and forest trees of many kinds. The male gypsy moth is yellowish brown, the female white, and larger than the male. In both sexes the wings are marked by dark lines and a dark lunule. The caterpillars, when full-grown, have a grayish mottled appearance, with blue tubercles on the anterior and red tubercles on the posterior part of the body, all giving rise to long yellow and black hairs. They usually pupate in July and the moth appears in August. The eggs are laid on tree trunks, rocks, etc., and hatch in the spring.