196 THE BUTTERFLIES OF THE BRITISH ISLES. 



and the spots on the outer margin of the hind wings are some- 

 times very small or entirely absent. 



The following particulars of the early stages are abstracted 

 from Mr. Frohawk's life-history of the species {Entomologist. 

 1892) :— 



Living females received in June were placed on a growing 

 plant of brome grass (Bromus asper\ and a few eggs were 

 deposited, some upon the blades of grass, others upon the 

 gauze-covered glass jar in which the plant was placed ; they 

 were laid singly, firmly adhering to whatever laid upon. The 

 first lot of eggs were deposited on June 14. The egg has a 

 pearly appearance, being whitish or yellowish-white in colour. 

 Ten days after the egg is deposited the young caterpillar 

 emerges by eating away the crown. Soon after hatching out 

 the young caterpillar makes a little tubular dwelling, drawing 

 together the edges of the grass-blade by spinning about three 

 or four stout cords of silk, which quickly contract, causing the 

 edges to draw together, and sometimes to overlap, forming a 

 compact short tube ; generally before spinning it nibbles off 

 the extreme edge of the blade where the silk is afterwards 

 attached. It feeds upon the blade both above and below its 

 abode, devouring so much that frequently only the midrib of 

 the blade remains, and the tube only just long enough to 

 conceal it ; it then shifts its quarters, and prepares a new home. 



On October 3, when one hundred and one days old, the 

 caterpillar was pale primrose-yellow, and the stripes of a 

 slightly darker hue, the white lateral line showing clearly, and 

 spiracles brownish ; the head pale buff with a faint lilac tinge, 

 with a black patch above the mouth and brownish at the sides. 

 In the previous stage the caterpillar was whitish-green with a 

 rather dark green line along the middle of the back, this line 

 bordered on each side by an almost white, very fine line, 

 followed by alternate darker and lighter lines, the lightest 

 being extremely fine ; " then a subdorsal darker green line, 



