184 



BRITISH BUTTEBFLIES 



Fig. 83.— The Brown Hair 

 STREAK — Male. 



white lines, the inner one of which is indistinct ; and on the hind 



wings are two others, the outer one being longer and more distinct 



than the inner. 



This biitterflv is hj no means an abundant insect, though it is 

 widely distributed, and in some places 

 plentiful. Its chief haunts are woods, 

 and we ma;) mention among its 

 favoured localities Epping Forest, 

 Monk's Wood in Cambridgeshire, the 

 wooded parts of South De^on and 

 Dorset, New Forest, ('olche.ster, and 

 Peterborough. 



The perfect insect is on the wing 

 from July to October, and the eggs are 

 deposited in the autumn on the twigs 

 of its food plant — the l)lackthorn 



{Pnimis spinosa). Tliese do not hatch till the following spring. 



Toward the end of June the caterpillar is fully fed. 



The colour of the caterpillar is light green, with two white stripes 



down the back, and two others along the sides. There are also two 



small oblique whitish lines on each side of each segment. 

 The chrysalis is smooth, and of a pale brown colour. 



The Black Hairstreali-, or White-letter Hairstreah 

 {Thecla W- album) 



The first of the above two popular names has been applied to 

 this species on account of the very deep brown colour of the upper 

 side, which colour is often a near approach 

 to black. The second is due to the W-shaped 

 bend of the white streak of the hind wings. 

 I'he gromid colour ot the under side (Plate 

 \'I, fig. 4) is grej-ish brown, with a bright 

 orange band, spotted with black near the 

 hind margin of the hind wings. 



W-albiim is a somewhat rare insect, but 

 is occasionally seen in plenty in a few loca- 

 lities, Cambridgeshire, Berkshire, Epping, 

 Colchester and Suffolk being among its chief resoi'ts. It is out 

 on the wing in July, and should be looked for in wooded country 

 where the common elm {Ulmns camijestris) and the wych elm 

 (U. montana), its food plants, exist. 



Fig. 84.— The Whitk- 

 letter Hairstreak. 



