Bui. 992, U. S. Dept. of Agriculture 



Plate IV. 



The Walnut Husk-Maggot. 



a, Black walnut showing discolored spot on skin made by husk-maggots mining within; 6, black 

 walnut stained by juice flowing from oviposition scar; c, husk-maggots in Persian walnut: 

 d, black walnuts with husk removed to show difference in hulling between sound and infested 

 nuts; nut on the left sound, on the right infested. All about natural size. 



