THE YOUNG NATURALIST. 



315 



Food Plants — Blackthorn {Prunus 

 sfrinosa.) Kirby adds " oak and other trees." 



Times of Appearance. — The Butter- 

 fly appears on the wing in June, and con- 

 tinues out till July. The egg is laid on the 

 Blackthorn, but does not hatch till spring. 

 The larva is full fed by the end of May. 

 This species was not known as British 

 till 1828. 



Habitat. — Woods. In this country it 

 is confined to very few counties. Derby- 

 shire. Huntingdonshire, Monmouthshire, 

 Northamptonshire, and Suffolk. Why its 

 range should be so restricted does not seem 

 easy to understand, as the larva feeds on so [ 

 common a plant. Abroad it is found in 

 Central Europe, France, Italy, and Scandi- 

 navia, Dalmatia and the mountainous dis- 

 tricts of Western Siberia. 



Variation. — Beyond the slight vari- 

 ation, already named, in the orange mark- 

 ings on the wing, I have heard of no 

 departures from the type in this species, 

 and there are no named varieties. 



BETUL^E, Linn. PI. 18., Fig. 5. 



" Butul.*:, L., Bet'ula, feeds on the Birch 

 (Betula alba)." — A.L. 



Imago. — PI. 18, Fig. 5. Male, dark 

 glossy brown, with a black dash at the disc, 

 and a faint yellowish patch before it. One 

 or two orange lunules at the anal angle. 

 Underside, yellowish brown, the disc streak 

 quite distinct, a silvery line, with dark 

 border inside, across the fore wing ; at the 

 costa there is a reddish brown wedge-shaped 

 mark, one side of which joins the hair-streak. 

 There are two similar silvery lines to the 

 hind wing, the inner one only crossing about 

 halfway, and forming the inner edge of a 

 larger wedge-shaped reddish patch. Hind 

 margin coppery red. The female resembles 

 the male, except that it has a larger orange 

 red band, beginning near the costa, and 

 extending nearly to the anal angle of the 

 fore wing. 



Larva. — The dorsal depression very 

 inconspicuous, the overlapping segments 

 forming almost a ridge, distinctly divided at 

 at each. Colour bright apple green, with 

 pale yellow lines and two rows of oblique 

 streaks of the same colour. Spiracles 

 whitish. Head brown and retractile. 



Pupa. — Of the usual form. Short, stout, 

 clear red brown in colour. Owen Wilson 

 says they are suspended, but he does not 

 say whether they also have the silken band 

 round the middle. Newman's larva changed 

 on the bottom of the breeding cage. I 

 should be glad to hear the experience of 

 ! those who have reared it freely. 



Food Plant. — The larva feeds on the 

 Birch (Betula alba), as its name implies. It 

 also eats Blackthorn (Prunus spinosa) and 

 other trees. Newman speaks of it as though 

 Blackthorn were its only food, but that is 

 not correct. 



Times of Appearance. — This butter- 

 fly is later on the wing than any other of the 

 genus. The earliest specimens emerge in 

 July, and they continue to appear for some 

 time, remaining out till September or even 

 October. The eggs are attached to the 

 twigs of the food plant, and do not hatch 

 till Spring. The larva may be found in May 

 or June, and they remain about three weeks 

 in pupa. 



Habitat. — This insect is widely dis- 

 tributed in England, except in the North- 

 Eastern portion, not occurring in Yorkshire, 

 Durham, nor Northumberland. It is recorded 

 for Cumberland on the strength of a speci- 

 men seen in Baum Wood, near Carlisle, by 

 Mr. J. B. Hodgkinson. Scotland appears to 

 be entirely without the species, though it is 

 common in some parts of Ireland. It has 

 not a very wide range on the Continent, 

 occuring in Central Europe, and the South- 

 ern portion of Russia. It extends to the 

 Southern portions of Siberia and the Valley 

 I of the Amoor. 



