44 THE BUTTERFLIES OF THE BRITISH ISLES. 



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 speci- 

 mens, 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. 



The egg (Plate 15), when freshly laid, is whitish, faintly 

 tinged with greenish ; it soon changes to yellow, and, later on, 

 turns orange and then dark violet. When the latter colour 

 appears, the little caterpillar may be expected to hatch out very 

 shortly. The eggs are placed upright on the foot-stalks of the 

 flowers, and may be readily found in June by searching the 

 blossom-clusters of hedge-mustard or cuckoo-flower. 



The caterpillar, when mature, is dull bluish-green, with 

 raised dots and warts ; from the former arise whitish hairs, 

 and from the latter longer blackish hairs. There is a white 

 line, or stripe, along the sides, and the underparts of the body 

 are greener than the back. Both in colour and marking the 



