342 LEPIDOPTERA. 



is much difference in the depth of the yellow ground colour, 

 even in specimens having only the normal angulated line. 



On the wing from May till September, but whether in 

 more than one generation is uncertain. 



Larva not certainly known. From the habits of the 

 moth it seems probable that the larva feeds in the roots 

 of thistles or allied plants, but as yet this is mere surmise. 



The moth is found commonly, among rough herbage, 

 almost everywhere ; and occasionally in abundance in clover 

 fields, but its partiality for thistles and knapweed is some- 

 what conspicuous. It is always alert and flies swiftly if 

 disturbed at any time in the day, but is more restless and 

 active towards dusk. In flight the darkness of its under 

 surface gives it a somewhat peculiar appearance, which is 

 enhanced by its singular action of shooting straight forward 

 for some distance when on the wing. Common throughout 

 England and Ireland, and probably Wales, though the 

 records there are only for the southern counties. In 

 Scotland it seems to be confined mainly to the Lowlands. 

 Abroad it is distributed almost all over Europe and Asia 

 Minor, and found in Northern Persia and the district of the 

 Caucasus. 



Genus 7. PHTHEOCHROA. 



Antennae long, slender ; palpi long, depressed, beaklike ; 

 face oblique, rough ; fore wings without a fold, surface 

 roughened with raised scales. 



We have two species, readily distinguished. 



A. Fore wings grey, roughened with conspicuous tufts of 



raised scales. F. rwjomnn. 



B. Fore wings white with a dark central band, raised 



scales minute and obscure. P. sodalmna. 



1. P. rugosana, IffV^.— Expanse | inch (18-20 mm.). 

 Head white ; fore wings grey with numerous conspicuous 

 tufts and lines of raised scales. 



