GEOMETRIDyE—WDIS. 285. 



which birch and alder abound ; on heaths among scattered 

 birches ; and very common about the alder-cars in fens ; 

 apparently throughout England, Wales, and Ireland ; also 

 the South and centre of Scotland, where it extends to the 

 Clyde Valley in the West, and to Moray in the East, and is 

 rather common in Perthshiie. Abroad it is found through- 

 out Central Europe, the temperate portions of Northern 

 Europe, Northern Italy, Eastern Siberia, Tartary, and Japan. 



Genus 3. lODIS. 



Antennae of the male pectinated, the tip filiform ; palpi 

 minute ; head smooth, transversely divided ; thorax and 

 abdomen slender, moderatel^^ smooth ; fore wings broad, 

 rather silky ; hind wings thin and silky, faintly angulated 

 behind. 



Larv^ long and slender, rather stiff; two small points on 

 the second and anal segments. 



Pup^ among leaves. 



We have but two species, which cannot be mistaken for 

 each other — /. vernaria being bright emerald-green ; /. lac- 

 tmaria faintly bluish-green, nearly white, and very much 

 smaller. 



1. I. vernaria, Z.— Expanse li- to If inch. All the 

 wings broad, soft silky green, almost pea-green ; on the fore 

 wings are two white transverse lines, and on the hind 

 one. 



AntennsB of the male pectinated with short curved ciliated 

 teeth, light brown, shaft white ; palpi short and blunt, pale 

 brown ; face smooth, dark purple-red or vermilion, banded 

 above by a transverse channel, the upper part of the head 

 being whitish-green, and between the antennae white; thorax 

 rather downy, with raised scales at the sides, green ; abdomen 

 smooth, but downy, rather paler green; lateral and anal 

 tufts inconspicuous. Fore wings moderately broad; costa 



