^J?^** 



LEPIDOPTERA. 26 1 



differ greatly in appearance. The general color of both 



sexes is a glassy steel-blue. In the female (Fig. 306) the 



fore wings are covered with scales, and 



there is a bright orange-colored band 



on the abdomen. In the male both 



pairs of wings are nearly free from 



scales. No better method of fighting 



. 1 • 1 1 r 1 .1 Fig. -?o6. — Sannina exitiosa. 



this pest has been found than to care- J 



fully watch the trees and remove the larvae with a knife as 



soon as discovered. 



The Pacific Peach-tree Borer, Sannina pacifica (S. pa- 

 cif'i ca). — On the Pacific Coast there is a peach-tree borer 

 that is distinct from the above, and appears to be an even 

 more serious pest. The larva is more difficult to remove 

 from the tree, as it bores into the solid wood. The female 

 of this species lacks the orange-colored band on the abdomen. 



The Currant Borer, Sesia tipuliformis (Se'si-a tip-u-li-for'- 

 mis). — This species is closely allied to the two preceding, 

 but is smaller, expanding only about three fourths of an 

 inch. There are but few scales on either pair of wings 

 except on the tip and discal vein of the fore wings and the 

 outer margin of the hind wings. The eggs are laid on the 

 twigs of currant. The larvae penetrate the stem, and de- 

 vour the pith; in this way they make a burrow in which 

 they live and undergo their transformations. The perfect 

 insects appear in June. Before this time the leaves of the 

 infested plant turn yellow. If such plants be cut and burned 

 in May the pest will be destroyed. 



The Pine Sesian, Harmonia pint (Har-mo'ni-a pi'ni). — 

 Frequently there may be seen on the trunks of pine-trees 

 large masses of resinous gum mingled with sawdust-like 

 matter. These are the results of the work of the larvas of 

 this insect, which bore under the bark and into the superficial 

 layers of the wood. The adult resembles the female of the 

 Peach-tree Borer, but the abdomen is more extensively 

 marked with orange. 



