THE INSECT WORLD. 



287 



retracted, and the tongue is obsolete, so that the insect is in- 

 capable of feeding. None of our American species attack culti- 

 vated plants or trees so as to become injurious, though in forests 



Fig. 320. 



Goal-moths, Piionoxystns robiimr, female and male, and their larva. 



young oak timber is sometimes badly injured by the Prionoxys- 

 his robini(X. 



There has been recently introduced into the Eastern United 

 States a European species known as the leopard-moth, Zcuzcra 

 pyrina, and this has become a pest on the shade-trees in several 

 of our Eastern cities. The male moths expand a little more than 

 an inch, the female over two inches, and both arc white, spotted 

 with black, whence the common name " leopard-moth." There 

 is great difficulty in dealing with insects of this character, owing 

 to their food habits. Fortunately, even in this imported form, 

 the natural checks seem to prevent its doing much injury to 

 orchards or country trees ; but in the cities and towns it threat- 

 ens the life of the shade-trees. The only recommendation to 



