ATTACKING THE LEAVES. 217 



effect of attracting to die tree their natural enemies, which 

 also multiply with great rapidity and make astonishing havoc 

 among their defenceless victims. The lady-birds and their 

 larvse, also the larvae of Syrphus flies and lace-wing flies, many 

 of which are referred to under No. 57, appear in abundance 

 among them, tearing and devouring them with the greatest 

 ferocity, and usually w^ithin two or three wrecks the armies 

 of lice are completely annihilated, and the leaves of the trees 

 appear clean again. Later in the season the lice appear a 

 second time, but occupy only the tender leaves at the ends of 

 the shoots, some of them usually remaining there during the 

 rest of the summer. On the approach of cold weather, males 

 are produced, and subsequently a stock of eggs is placed by 

 the females about the base of the buds and in the fissures of 

 the bark of the branches, where they remain unhatched until 

 the following spring. 



These lice may be killed by thoroughly drenching them 

 with w^eak lye, strong soapsuds, or tobacco-water, but what- 

 ever solution may be used it must come in contact with the 

 lice in order to be effectual; dipping the extremities of the 

 limbs in such solutions, where such a course is practicable, will 

 quickly destroy them. The easiest remedy, however, is to aid 

 nature by introducing among the colonies a number of lady- 

 birds and other enemies, who at once set to work to devour 

 them with great vigor. A very minute Ichneumon fly, a 

 species of Aphidius [Trioxys cerasphis Fitch), is parasitic upon 

 these lice and destroys large numbers of them. 



No. 116.— The Ursula Butterfly. 



Limenitis Ursula Fabr. 



This is a medium-sized but handsome butterfly, which is 

 seen on the wing during the months of June and July. It is 

 represented in Fig. 223. Its wrings are of a blackish-brown 

 color glossed v/ith a bluish tint, and with three marginal rows 

 of bluish crescents of varying size. In the female the inner 

 row is less marked, and each crescent is supported behind by 



