144 LEPIDOPTERA. 



far broader, the spots on the forewings similarly placed, but 

 distinctly blue-black, larger, more elongated, and more strik- 

 ing ; and the nervures very thick and conspicuous. Hind 

 wings also a little more distinctly spotted between the 

 nervures. Antennae slender and threadlike, but with a large 

 tuft of downy white scales at the base, and clothed with the 

 same to the middle ; abdomen stout and tapering to a long 

 point, where is a conspicuous ovipositor, blackish, thinly 

 scattered with whitish scales. Underside of all the wings in 

 both sexes similar to the upper; body grey with whitish 

 scales ; legs black ; slightly variable in the size and intensity 

 of the blue-black spots, and, in the female, in the size of the 

 immaculate space near the costa — which is sometimes supple- 

 mented with a similar space before it — also, occasionally, in 

 the female, by the spots in the middle area of the forewings 

 coalescing and running into long blotches. In a specimen in 

 the collection of the late Mr. F. Bond is a beautiful instance 

 of this in which the spots have united into long blue-black 

 stripes. 



On the wing from the end of June to the beginning of 

 Auofust. 



o 



Larva 2 inches long, rather stout and slightly flattened, 

 with segments deeply divided ; head prominent, rounded, 

 rather small, blackish brown ; second segment with a broad 

 rectangular dorsal plate of the same colour ; anal segment 

 with a similar, but smaller, lunate plate ; body tapering 

 slightly to the tail, brownish white or yellowish white, whiter 

 upon the back ; with the usual raised spots large, conspicuous, 

 black, each bearing a thin bristle. When younger the dorsal 

 plate is more bell-shaped, and toothed at the back, the anal 

 segment blackish, and the general colour pale yellow ; spots 

 always conspicuously black. In the trunks, branches, and 

 even shoots and twigs of trees and shrubs — Poplar, Aspen, 

 Horse-chestnut, Ash, Elm, Sycamore, Birch, Willow, Sallow, 

 Hawthorn, Lilac, I'rivet, Holly, Alder, Pear, Apple, Quince, 



