THE ENGRAILED. 



313 



considered specifically distinct from the, normally, single-brooded 

 crepusculariaj others hold the opposite view. The March and 

 April moths are generally rather browner in colour than those 

 appearing in May and 

 June, but I have some 

 specimens taken in 

 Wiltshire at the end of 

 March, which are quite 

 as pale as any example 

 in the May — June 

 series. Probably, we 

 should be right in re- 

 garding crepusciilaria 

 as the older stock from 

 which the double- 

 brooded race, bistor- 

 tata^ has sprung. The 

 former has a more ex- 

 tensive range, as it 

 inhabits Northern 

 Europe (Sutherland- 

 shire in British Isles), 

 whilst bistortata seems 

 to be confined to Cen- 

 tral Europe. A Perth- 

 shire form of the May 

 — June race is shown 

 on Plate 136, Fig. 7 ; 

 and an example of ab. 



delamereiisis^ White, from Delamere Forest, Cheshire, is repre- 

 sented by Fig. 8. Figs. 6 5,7 ? j represent examples of the 

 March and April race. Black or blackish forms, with the 

 sub-marginal line more or less distinctly white, occur in both 

 races, chiefly in Glamorganshire, South Wales. 



Fig. 19. 



Small Engrailed, at rest. 



(Photo by W. J. Lucas.) 



