THE HAIRSTREAKS, COPPER S AND SLUES 187 



The chief food plants of this species are the bramble (Rubus 

 fruticosus), the birch (Betula alba), and the broom (Cytisus 



The perfect insect flies in May and June, and the eggs are 

 deposited during the latter month on the above plants. The 

 caterpillars are full fed in July, and change to the chrysalis state 

 towards the end of the summer. 



The colour of the caterpillar is pale green, with a yellow stripe 

 and several white oblique lines along the sides, also a yellowish 

 stripe down the back. 



The chrysalis is short and thick, and of a dark brown 

 colour. 



The Large Copper (Polyommatus Dispar] 



Our next genus contains only two British species. The first of 

 these the Large Copper was once a common insect at Whittlesea 

 in Cambridgeshire, and in some of the fens of Huntingdonshire, 

 but is now feared to be quite extinct, as none have been seen for 

 many years. The last capture was made in 1847 in Huntingdonshire. 

 However, it may turn up again ; and even if it does not, it would 

 be a pity to allow the memory of so fine an insect to die out ; so 

 we find room to figure it (Plate VI, fig. 8), and append a few 

 remarks. 



There is a very great difference between the male and the 

 female. The former is of a brilliant copper hue, and all the wings 

 have a black margin and a black streak near the middle. The female 

 is larger, and the coppery colour is much redder. The black border 

 of the fore wings is wider, and there are also several large black 

 spots on these wings. The hind wings are almost entirely covered 

 with black, with the exception of a broad coppery band near the 

 hind margin. 



The food plant of the caterpillar appears to have been the water 

 dock (Eumex Hydrolapathum), on which the eggs were laid late 

 in the summer. It is probable that the caterpillar was a hyber- 

 nator, seeking its winter shelter while still very young ; and it was 

 full fed in June. 



Its colour was green, with a darker stripe of the same colour on 

 the back ; and the chrysalis was attached by anal hooks and a cord 

 round the body. 



