The earliest writers on English insects called this butterfly "Vernon's Half Mourner," or "The Greenish Half Mourner." It was first mentioned by Petiver, some two hundred years ago, and about that time only two British specimens were known. One of these was taken in Cambridgeshire, and one at Hampstead. According to Lewin, who wrote about it in 1795, the name "Bath White" was given to the butterfly "from a piece of needlework executed at Bath by a young lady, from a specimen of this insect, said to have been taken near that place." In 1796 Donovan only knew of the Bath specimen; and in 1803 Haworth mentions a faded specimen taken in June at Gamlingay in Cambridgeshire. The species is more or less common in many parts of Europe, but it seems to be most at home and abundant in the south. Its range extends to North Africa, Madeira, the Canary Isles, and the temperate parts of Asia, including Northern China and Corea. The Orange-tip (_Euchloë cardamines_). This butterfly (Plate 17), as its name suggests, has a large patch of orange colour on the outer third of its white, or creamy white, fore wings, and the extreme tip is blackish; at least, this is so in the male. The female is without the orange patch, and this is replaced by a smaller one of blackish-grey. The lower portion of this patch is broken up by the ground colour, and by white spots on the outer margin and around the tips of the wings. The hind wings, in both sexes, appear to be dappled with greyish-green, and this is caused by the green marking on the under surface of the wings showing through. Some specimens, chiefly from Ireland, have all the wings in the male, and the hind wings in the female, distinctly tinged with yellow. The discal black spot varies in size and in shape; often it is roundish, and sometimes it is crescent-like. It is always larger in the female than in the male, and may be entirely absent in the latter sex; but this probably occurs very rarely. Usually the orange patch of the male extends very near to the inner angle of the wing, but sometimes it is continued through to this point. It ranges in colour from deep to pale orange, and occasionally to almost yellow. Small specimens, some not more than one inch and a quarter in expanse, occur from time to time. In these dwarfs the orange patch does not reach beyond the black discal spot, which in normal specimens it usually does. This small form has been considered a distinct species, and the name _hesperidis_ has been proposed for it. Female specimens with splashes or streaks of the male colour on the upper or the under sides have been noted not infrequently; and more rarely specimens with one side entirely male and the other entirely female have been taken.