52 THE BUTTERFLIES OF THE BRITISH ISLES. 



female usually has the black borders spotted with yellow, but 

 in some examples these spots are almost (Plate 24, Fig. 1) 

 or quite absent. Another form of the female, known as var. 

 helice (Plate 24, Fig. 2), has the orange colour replaced by 

 yellowish-white, and in some years is not altogether uncommon. 

 Between this yellowish-white at one end of the colour range 

 and the typical orange at the other, specimens showing all the 

 intermediate shades have been obtained, chiefly by rearing the 

 butterflies from eggs laid by a female helice. One of these 

 intergrades will be seen on Plate 24, Fig. 3. The males vary, 

 especially bred ones, from " deep rich orange to the palest 

 chrome yellow ; the marginal bands also vary in width ; in 

 many examples the yellow nervules run through the borders of 

 all the wings. A large proportion of the males have the hind 

 wings shot with a beautiful amethystine blue" (Frohawk). 



The egg (Plate 23) is oval, tapering towards each end, very 

 pale yellowish in colour at first, but afterwards becoming darker 

 yellow, and then pink. The eggs are laid, as shown in the figure, 

 on the upper side of a leaf of clover or lucerne, sometimes 

 singly, but often in small batches. 



The caterpillar when full grown is deep green with minute 

 black dots, from which fine hairs arise, and a pink-marked 

 yellow, or whitish, spiracular line. The head is also green, 

 rather downy, and small in size. When first hatched the 

 caterpillar is brownish, but soon changes to greenish. It feeds 

 on clover (Trifotium), trefoil (Lotus), melilot (Melilotus\ etc., 

 in June and again in September or October. 



The chrysalis is yellowish-green above, somewhat paler 

 below ; the wing-cases are rather deeper in tint than the 

 thorax and back, and have a central black speck and a row 

 of slender marks at the edges. The body is marked with a 

 splash of reddish and tiny black dots on the under side. The 

 beak-like projection from the head is dark green above and 

 yellow beneath. 



