70 THE MOTHS OF THE BRITISH ISLES. 



The species is perhaps most common in the southern and 

 eastern counties of England, but seems to be pretty generally 

 distributed throughout the country, and extends into Scotland 

 as far as Moray. In Ireland it has a wide range but is only 

 common near Londonderry. Abroad it is found in Central and 

 Northern Europe, and as far east as Amurland and Ussuri. In 

 America it is represented by P. dimidiata, H.-S., which does not 

 seem to be really specifically distinct. 



The Lesser Swallow Prominent {F/ieosia dictcEoides). 



Very similar to the last species, but generally smaller, and the 

 ground colour has usually less brown in it ; the chief character, 

 however, by which it may be distinguished, is the broader and 

 clearer white wedge-shaped mark between veins one and two 

 on the fore wings. Reference to the figures of each species on 

 Plate 28 will show this at once. 



The eggs are greenish white, and the full-grown caterpillar is 

 purplish brown on the back merging into violet on the sides ; 

 there is a broad yellow stripe along the spiracle area ; the head 

 is violet, faintly marked with black. A noticeable feature of 

 this caterpillar is its varnished appearance. It feeds on birch 

 in June and July, and sometimes in September and October. 

 The early stages are figured on Plate 29, Figs. 3, 3^, and -^b. 



The species has a somewhat similar distribution to that 

 mentioned for the preceding, but it seems to be commoner in 

 the North of England and in Scotland than elsewhere in the 

 British Isles. 



The Pebble Prominent (Notodo?ita ziczac). 



This moth varies in the colour of the fore wings from pale 

 ochreous brown to a darker brown tinged with reddish ; the 

 usual pale greyish patch in the middle of the costal area is 



