The monarch is perhaps the best-known butterfly. Its wings are orange with black veins and black margins. The margins are sprinkled with white and orange spots. This large butterfly has a wingspan of up to 4 inches. They are often seen flying from plant to plant, sipping nectar from a wide variety of flowers. Monarchs lay pale green eggs on the leaves of milkweed, a plant that has a white milky sap. The eggs hatch in about 4 days. The caterpillar is banded with white, black, and yellow stripes and has a pair of soft spines at both its front and rear end. It feeds on the leaves of milkweed for about 10 days, and when fully mature, reaches a length of about 2 inches. It then attaches itself to a leaf or stem and forms a cocoon (chrysalis). The chrysalis is a jade green color with gold trimmings. It slowly darkens. After about 12 days, the butterfly emerges from the chrysalis. There may be up to 4 generations a year. The monarch is the only butterfly species that migrates yearly both north and south. In the spring you can observe them migrating in a northerly direction, laying eggs and sipping nectar in the process. In the fall they migrate in a southerly direction. They are capable of flying up to 2,000 miles during a migration. Monarchs that emerge in late summer and fall in the East or Midwest spend the winter in fir forests in northern Mexico; monarchs in the West spend the winter on the coast of central and southern California in groups of pine, cypress, and eucalyptus. There are also certain stands of trees along the Atlantic and Gulf Coasts and the Great Lakes where they are seen yearly.