Green-veined white (Pieris napi)

It is found in meadows, hedgerows and woodland glades but not as often in gardens and parks like its close relatives the large and small whites, for which it is often mistaken. Like other "white" butterflies, the sexes differ. The female has two spots on each forewing, the male only one. The veins on wings of the female are usually more heavily marked. The underside hind wings are pale yellow with the veins highlighted by black scales giving a greenish tint, hence green-veined white. Unlike the large and small whites two, it rarely chooses garden cabbages to lay its eggs on, preferring wild crucifers. Males emit a sex pheromone that is perceptible to humans, citral,  the basic flavour-imparting component of lemon peel oil.