Moth wing scales. Coloured scanning electron micrograph (SEM) of a section through a scale from the wing of a silk moth (Bombyx mori). All butterflies and moths have these transparent scales on their wings, which have tiny ridges on them. The ridges break up and reflect light, giving the wings their shimmering iridescent appearance. Magnification: x26,500 when printed at 10 centimetres wide.