90 BRITISH BUTTERFLIES AND MOTHS 



believe, it occurred in various parts of the country, 

 where it is not now found. 



It is our largest native butterfly ; the expansion of 

 the wings varying from 3J to 4 inches. The fore-wings 

 are of a deep straw-colour, with a large black patch at 

 the base, and with the veins black and some black spots 

 towards the costa ; a black band runs along the hind 

 margin, enclosing eight straw-coloured spots. The hind- 

 wings are straw-colour, with the inner margin blackish, 

 and with a round brick-red spot at the anal angle ; to- 

 wards the hind margin is a broad bluish-black band ; 

 near the middle of the hind margin there is a black 

 prolongation forming a tail (whence the English name 

 of " Swallow-tail "). 



The very beautiful larva is bright green, each segment 

 bearing two black bands, of which the hinder band is or- 

 namented with six orange spots. It feeds on milk-parsley 

 (Peucedanum palustre) and other Umbelliferae, and may 

 be met with from the end of June to the end of August. 



The perfect insect begins to appear at the end of 

 May, and may be found up to August. Those who 

 have once had the pleasure of seeing it on the wing can 

 never forget its elegant appearance. 



FAMILY I. PAPILIONID.E. Subfamily Pieridi. 



GONEPTERYX RHAMNL THE BRIMSTONE 

 BUTTERFLY. 



This pretty species is common in the south of Eng- 

 land, and generally distributed ; in the midland counties 

 it is scarcer, and disappears entirely before we get as far 

 north as Scotland, the northern limit of its food plant, 

 buckthorn, not extending to the Tweed. 



