females to oviposit near them. It is not as well understood why oviposition occurs off of the host plant, but researchers have suggested that it may be to avoid exposure of eggs to predators associated with the host plant. Life cycle Egg The eggs are white and round, but flattened at the top and bottom. They exhibit a pebbled surface, while the micropylar area, or the area where the sperm fertilized the egg, is brown and sunken. The surface of the egg is generally more sculptured compared to the eggs of other butterflies, likely due to the thick chorion that has evolved to protect the overwintering egg from predators, parasitoids, and adverse environmental conditions. Around 75 eggs are produced per female. However, the eggshells are not consumed upon hatching, despite its high nutrient content. The eggs are generally laid on the underside of flower heads, leaves, sticks, stones, moss, clumps of dirt, and sometimes on the larval foodplant. The female may or may not oviposit on the foodplant itself, and may often lay her eggs over a meter away from the plant. The embryo develops into first instar larva within a month of oviposition but the egg does not hatch until the snow melts the next spring. Larva The larva completes five instars before pupating, developing over a period of around 10 to 12 weeks. The first instar larva has a black body with many hairs, and a dull black head. As the larva feeds on its host plant S. lanceolatum, it sequesters in its body sarmentosin from the plant, causing the larva to become distasteful to predators. Conspicuous yellow markings appear on the body after the second instar, warning off predators, as the larva stores higher levels of sarmentosin. The fifth instar larva is black, with many short fine black hairs littered over its body. It sports two lateral and two dorsal rows of bright yellow spots. It has small and pale yellow vestigial osmeteria, a special organ just behind the head that resemble feelers. Since they may not always hatch close to their foodplant, the larvae have a fast, directional search pattern. They tend to feed rapidly on their larval host plant, then move to a basking location on open ground up to a few meters away for thermoregulation. If disturbed, the larvae twitch violently, then drop to the ground to seek cover, and may discharge a bad-smelling