THE ORANGE UNDERWING 93 



PLATE XLVIII 



THE ORANGE UNDERWING (2) 



There are really two kinds of Orange Under- 

 wings, the light and the dark. But they come 

 out at the same time, and fly about together, 

 and are so much alike that it is not at all easy 

 to tell the one from the other. The time to look 

 for them is about the middle or end of March, 

 and then, if you go into a large wood on a 

 warm, sunny morning, you may sometimes see 

 them flying about among birch trees. They are 

 very fond, too, of visiting sallow, or "palm," 

 bushes, and sucking the sweet juices from their 

 golden-yellow catkins. But the moment that 

 the sun is clouded over they seem to disappear, 

 and you will see them no more until it begins 

 to shine again. 



The caterpillars of both the Orange Under- 

 wings are dull green in colour, with yellow lines 

 on their backs and sides, and when they walk 

 they hunch their bodies up into loops, just like 

 the "stick" caterpillars of such moths as the 

 "swallow-tail" and the "willow beauty." That 

 of the Light Orange Underwing feeds on aspen, 

 and that of the Dark Orange Underwing upon 

 birch. You may find both in June and July. 



