"On the underside the groundcolour is very variable, with white with a slight to strong ochraceous tinge, greenish white or sulphur-yellow. The fore wing is typically without markings, in some specimens with a patch of sulphur-yellow on either side of base of median nervure, in the very yellow examples the tornal area is often widely greenish white, in others ("Catopsilia catilla", Cramer) it bears a spot variable in size on the discocellulars. This spot has a pearly centre and an outer reddish line. Many specimens have an irregular angulated narrow discal reddish line (the colour varies in intensity) that runs from the costa obliquely outwards to vein 7, and then obliquely inwards to vein 2, though this line is often absent in specimens that bear the discocellular spot; apex and termen sometimes very narrowly reddish. The hind wing is typically uniform, without markings; in var. "catilla" there is a single small spot at the end of the cell similar to that on the fore wing, sometimes this spot is much larger with a narrow outer reddish ring, sometimes it is accompanied by a similar spot at base of interspace 5; when two spots are present they may be entirely separate, or their outer rings may coalesce; again, some specimens have a highly irregular discal reddish line (often reduced to a series of minute spots) that extends from the costa to vein 1; finally, the majority of specimens have a series of minute red terminal dots at the apices of the veins."