THE YOUNG NATURALIST. 



339 



Larva. — Onisciforme, with a depression 

 on the back as in the " Blues," the segments 

 appear to overlap. Head small and retrac- 

 tile ; colour brownish green. A dorsal row 

 of pinkish arrow heads. Spiracular line 

 light bordered with brown. Spiracles brown. 



Pupa. — Short and stumpy. Dull red- 

 dish brownish. On or under the surface of the 

 earth. I would be glad to hear from those 

 who have reared this species freely, if its 

 pupa is ever attached. 



Food Plants.— The larva is generally 

 understood to feed on oak only, and in a 

 state of nature appears to prefer the upper 

 branches. Owen Wilson also gives Sallow 

 and Newman conjecturs that it may some- 

 times feed on Ash. 



Times of Appearance. — This but- 

 terfly appears on the wing in July, and the 

 eggs remain on the oak twigs over the win- 

 ter, hatching in May ; the larva is full grown 

 in June. 



Habitat. — Woody places all over Brit- 

 ain, and equally well distributed over 

 Europe, but not extending further. 



Variation. — Only one form is named, 

 Bellus, Gerh., which I do not know. 

 Abnormal forms are very rare. Mr. S. 

 Stevens has a specimen with the male 

 colour on one side, and female on the other. 

 A specimen with a wedge-shaped orange 

 spot on the forewings is recorded by Mr 

 Norgate, of Sparham, at page 69 of the 

 Entomologist for 1874. This reminds one 

 of Betula, q.v. 



W-ALBUM, Kn. PI. 18, Fig. 3. 

 The Black Hair streak. 



" W-Album, Kn., W-Al'bum, on account 

 of the white on the underwings." — A.L. 



Imago. — PI. 18, Fig. 3. Dark brown, 

 with one orange spot at the anal angle of the 

 hind wing, often very indistinct. Under- 

 side ashy brown, with a row of orange 

 lunules at the hind margin, most distinct at 

 anal angle. A white line crosses both wings, 



and forms a W near the inner margin of 

 each. 



Larva. — Pale bright green, with a 

 depression on the back of a brownish colour. 

 The segments overlap, and the ridges at the 

 edge of this dorsal depression are pale 

 yellow. On the sides of each segment are 

 two pale yellowish lines. Head dark brown 

 and retractile, the sides project over and 

 hide the prolegs and claspers. The whole 

 surface is covered with soft delicate hairs. 



Pupa. — Short and stumpy, attached by 

 the tail and by a belt of silk round the 

 middle. 



Food Plants.— Elm appears to be the 

 natural food of the larva, but it is also 

 found on the Wych Elm, and will eat 



Blackthorn. 



Times of Appearance. — The butter- 

 fly appears at the end of June or in July, 

 and continues on the wing until August. 

 The egg is laid on the elm twigs in July or 

 August, and remains in that state till spring, 

 hatching about May. The larva is full fed 

 in June, and remains about a fortnight in 

 pupa. 



Habitat. — Parks, woods, and lanes. 

 Not of general distribution in England, 

 though occuring in many places. It is not 

 found in the more Northern counties, nor 

 so far as I know, in Scotland or Ireland. 

 It is found in Central and Southern Europe, 

 in Northern and Eastern Asia and Asia 

 Minor. 



Variation. — Not a variable insect, and 

 no form of it is named, while aberrations 

 are exceedingly rare. A very beautiful 

 specimen is figured in Newman's Butter- 

 flies, and also in Mosley's " Illustrations." 

 It has the hair-streak represented by a 

 white band, broadest at the costa, and 

 tapering to a fine line about the middle of 

 each wing. It was taken in Old Hall Wood, 

 near Ipswich, in 1859 or i860, and is now in 

 Mr. Sidney Webbs collection. 



