Welcome to the butterfly wing pattern module of Class Insecta. Most butterfly and moth wings are covered with a dense mosaic of tiny individually colored scales forming a myriad of striking color patterns and designs. This beauty has elevated human perception of butterflies to a level of heightened appreciation. As you browse the six posters, you'll learn about wing structure, design analysis, pattern formation and adaptational benefits. Use the links on the left to explore the Fritillaries, Coppers, Monarchs, Painted Ladies, Sulphurs and Owl Butterflies. Butterflies and moths belong to the order Lepidoptera. This name means "scale-wing" in Latin and refers to the scale cell structures found on the wings. As is usually the case with insects, the closer you study them, the more you'll discover. Butterfly and moth wings are marvelously elaborate structures above and beyond the beauty of their patternation. The wings are predominantly a transparent or brownish epidermal membrane no more than 2 cell thick that spans the spaces between a network of wing veins that fan out into the wing shape. The shape and size of wings varies between species and usually takes on a characteristic shape that may include scalloping, lobes and even trailing hair-like slivers. The scales grow out of the epidermal membrane and are comprised of a basal socket cell and a flattened scale cell. In the case of butterflies, these scales are organized into orderly rows that radiate out in a perpendicular fashion to the base of wing. In comparison, most moths have a random distribution of scale cells. There are generally two types of scale cells. Ground scales are typically small and carry the background coloration of the design. A second type is known as the cover scales and are usually larger and more colorful, bearing the main pattern elements of the particular design. (continued...)